comp.tf - User contributions [en]

Hildreth

2017-08-10T01:34:54Z

81.147.69.112: /* Highlander */

{{stub}}
{{TabsHeader
|name1=Overview |link1={{PAGENAME}}
|name2=Results |link2={{PAGENAME}}/Results
|This=1
}}
{{NewInfobox Player
|id=Hildreth
|image=Hildreth.png
|caption=Hildreth at RewindLAN 2017
|name=Hildreth Harris
|romanized_name=
|birth_date=
|death_date=
|country=United Kingdom
|country2=England
|status=Active
|years_active=2009 - ''Present''
|team=Lowpander
|role=Demoman
|format=6s
|sponsor=
|ids=
|nicknames=King of Highlander, Hildoge
|site=
|etf2l=14394
|tftv=Hildreth
|steam=76561197995254867
|twitch=Hildreth
|youtube=Hildreth1101
|twitter=Hildreth1101
|facebook=
|gplus=
|fanclub=
|playlist=
|achievements='''Highlander''' {{Medal|1st}} {{LeagueIconSmall|ugc|link=UGC#Highlander|name=Platinum Season 8}} {{LeagueIconSmall|ugc|link=UGC#Highlander|name=Platinum Season 9}} {{LeagueIconSmall|wireplay|name=9v9 Season 11}}{{LeagueIconSmall|etf2l|link=ETF2L_Highlander_Season_6|name=HL Season 6}} {{LeagueIconSmall|etf2l|name=Experimental Cup #6}} {{LeagueIconSmall|tftv|name=TeamFortress.TV Highlander Invitational #2}} {{Medal|2nd}} {{LeagueIconSmall|etf2l|link=ETF2L Highlander Season 5|name=HL Season 5}} {{LeagueIconSmall|etf2l|link=ETF2L Highlander Season 8|name=HL Season 8}} {{Medal|3rd}}/{{Medal|sf}} {{LeagueIconSmall|etf2l|link=ETF2L Highlander Season 7|name=HL Season 7}} {{LeagueIconSmall|DeutschLAN|link=DeutschLAN 2015}} '''6v6''' 
|1stplace={{LeagueIconSmall|infoshow|InfoShow LAN Party 2015}}
|2ndplace={{LeagueIconSmall|etf2l|link=ETF2L 6v6 Season 13|name=ETF2L 6v6 Season 13: Division 2C}} {{LeagueIconSmall|etf2l|link=ETF2L 6v6 Season 15|name=ETF2L 6v6 Season 15: Division 1}} {{LeagueIconSmall|tftv|link=Gimmicks, Guts & Glory}}
|3rdplace=
|4thplace=
|team_history='''6v6'''
{{TH|2010 - 2011 | LagTastic Gaming |no-link=true}}
{{TH|2012 - 2013 | Furbo Pandas}}
{{TH|2013 - 2014 | Team Decerto}}
{{TH|2014 - 2014 | Lowpander}}
{{TH|2015 - 2015 | Hello Kitteh Ninjas!}}
{{TH|2017 - 2017 | The Enigma Zone Crew}}
{{TH|2016 - Present | Lowpander}}

'''Highlander'''
{{TH|2010 - 2011 | Lazytown Regulars|no-link=true}}
{{TH|2011 - 2012 | Pandamonium|no-link=true}}
{{TH|2012 - 2013 | Unbelievably Brave Sweethearts|no-link=true}}
{{TH|2013 - 2016 | Highpander }}
{{TH|2016 - 2016 | Tourettes Chessclub }}
|retired=
|prize_money= {{PM|2009 - present|€1935}}
}}

'''Hildreth''' is an English Highlander and 6v6 [[Demoman]] who currently plays for, and leads [[Highpander]] in the [[ETF2L]] Premiership. She has also been a caster for several casting organizations, a news-writer, and captain of the England National Highlander team on 3 occasions. She has organised various tournaments including the EU vs NA Highlander showmatches and [[TeamFortress.TV]] Highlander invitational. The ex-[[ETF2L]] admin formed Highpander after playing for American teams in UGC North America and is currently one of the most experienced players in ETF2L today.

=== 6v6 ===
Hildreth started playing 6v6 in 2009, creating LagTastic Gaming to play in Division 6 of ETF2L during Season 7. She would stay on the team until January 2012, where she would then try his luck on The Devils Rejects, only to be kicked from the team within a month. She then formed [[Lowpander]], known originally as Furbo Pandas who would climb from Division 2 to Premiership level over the next 4 seasons, beating Last Man Standing in the Season 15 relegation playoff. After being sponsored by [[Decerto]], his team managed a 7th placed finish, retaining their Premiership spot. The team did however fold at the end of [[ETF2L 6v6 Season 16|ETF2L Season 16]], only to reform during [[ETF2L 6v6 Season 18|ETF2L Season 18]] with new players from Highlander. They managed another 7th placed finish, retaining their Premiership spot again after winning the relegation playoff once again. The team then folded after a poor start to the next season, Hildreth has since taken a break from 6v6 playing briefly for [[Team Colonslash]] before joining [[Hello Kitteh Ninjas!]] and helping them to a 1st place finish in High during Season 21. 
Later on, Hildreth played for Team Infomax during [[Gamers Assembly 2016]] and reformed [[Lowpander]] for [[ETF2L 6v6 Season 23|ETF2L Season 23]]. The team went on to win [[ETF2L 6v6 Season 25/High|ETF2L Season 25 High Playoffs]]; defeating 2nd and 1st seed teams and subsequently booking themselves a Premiership spot for [[ETF2L 6v6 Season 26/Premiership|ETF2L Season 26]]. 
In January 2017 she competed at the North American LAN [[Esports Arena Rewind 2017/Open|Esports Arena Rewind 2017]] with [[The Enigma Zone Crew]] in the open tournament.

=== Highlander ===
She started his European highlander journey at '''LagTastic Gaming Highlander''' in the [[ETF2L Highlander Community Challenge]], though she spent most of the tournament mercing for this American team, [[Lazytown Regulars]]. After this, she went on to join Unbelievably Brave Sweethearts, who were formed from the remains of Lazytown Regulars and played in North American Highlander in [[UGC]]. After finishing both top 8 and 4th on two occasions with uBs, Hildreth joined the new super team The Syndicate as a backup in season 8, who went on to win the UGC Platinum title. During Season 9 Hildreth was moved up to a main spot on Medic, however the majority of the title winning side had changed and The Syndicate finished in 4th place.
With this experience under her belt, she kept quiet in the lower divisions, until she brought her [[UGC]] team to Europe. [[Unbelievably Brave Sweethearts]] did well in [[ETF2L]], but eventually fell short to make the climb to the Premiership division, finishing in 3rd place during Season 4 of ETF2L.

After Season 4, she then began creating [[Highpander]] together with [[stevepander]] and would eventually win the Premiership in Season 6, beating [[itsallgood]] in the finals. The team has been in the top 3 of every season since it's formation and are known as one of the best Highlander teams in Europe currently.

==Trivia==
*According to stabbystabby, [[hildreth]] is a fan of cheese sandwiches.
*Hildreth is the owner of a Community Stickybomb Launcher, awarded to individuals who have made significant, valuable contributions to the Team Fortress 2 community.

==Latest Tournament Matches==
{{Player matches table}}

Hildreth

2017-08-10T01:34:12Z

81.147.69.112:

{{stub}}
{{TabsHeader
|name1=Overview |link1={{PAGENAME}}
|name2=Results |link2={{PAGENAME}}/Results
|This=1
}}
{{NewInfobox Player
|id=Hildreth
|image=Hildreth.png
|caption=Hildreth at RewindLAN 2017
|name=Hildreth Harris
|romanized_name=
|birth_date=
|death_date=
|country=United Kingdom
|country2=England
|status=Active
|years_active=2009 - ''Present''
|team=Lowpander
|role=Demoman
|format=6s
|sponsor=
|ids=
|nicknames=King of Highlander, Hildoge
|site=
|etf2l=14394
|tftv=Hildreth
|steam=76561197995254867
|twitch=Hildreth
|youtube=Hildreth1101
|twitter=Hildreth1101
|facebook=
|gplus=
|fanclub=
|playlist=
|achievements='''Highlander''' {{Medal|1st}} {{LeagueIconSmall|ugc|link=UGC#Highlander|name=Platinum Season 8}} {{LeagueIconSmall|ugc|link=UGC#Highlander|name=Platinum Season 9}} {{LeagueIconSmall|wireplay|name=9v9 Season 11}}{{LeagueIconSmall|etf2l|link=ETF2L_Highlander_Season_6|name=HL Season 6}} {{LeagueIconSmall|etf2l|name=Experimental Cup #6}} {{LeagueIconSmall|tftv|name=TeamFortress.TV Highlander Invitational #2}} {{Medal|2nd}} {{LeagueIconSmall|etf2l|link=ETF2L Highlander Season 5|name=HL Season 5}} {{LeagueIconSmall|etf2l|link=ETF2L Highlander Season 8|name=HL Season 8}} {{Medal|3rd}}/{{Medal|sf}} {{LeagueIconSmall|etf2l|link=ETF2L Highlander Season 7|name=HL Season 7}} {{LeagueIconSmall|DeutschLAN|link=DeutschLAN 2015}} '''6v6''' 
|1stplace={{LeagueIconSmall|infoshow|InfoShow LAN Party 2015}}
|2ndplace={{LeagueIconSmall|etf2l|link=ETF2L 6v6 Season 13|name=ETF2L 6v6 Season 13: Division 2C}} {{LeagueIconSmall|etf2l|link=ETF2L 6v6 Season 15|name=ETF2L 6v6 Season 15: Division 1}} {{LeagueIconSmall|tftv|link=Gimmicks, Guts & Glory}}
|3rdplace=
|4thplace=
|team_history='''6v6'''
{{TH|2010 - 2011 | LagTastic Gaming |no-link=true}}
{{TH|2012 - 2013 | Furbo Pandas}}
{{TH|2013 - 2014 | Team Decerto}}
{{TH|2014 - 2014 | Lowpander}}
{{TH|2015 - 2015 | Hello Kitteh Ninjas!}}
{{TH|2017 - 2017 | The Enigma Zone Crew}}
{{TH|2016 - Present | Lowpander}}

'''Highlander'''
{{TH|2010 - 2011 | Lazytown Regulars|no-link=true}}
{{TH|2011 - 2012 | Pandamonium|no-link=true}}
{{TH|2012 - 2013 | Unbelievably Brave Sweethearts|no-link=true}}
{{TH|2013 - 2016 | Highpander }}
{{TH|2016 - 2016 | Tourettes Chessclub }}
|retired=
|prize_money= {{PM|2009 - present|€1935}}
}}

'''Hildreth''' is an English Highlander and 6v6 [[Demoman]] who currently plays for, and leads [[Highpander]] in the [[ETF2L]] Premiership. She has also been a caster for several casting organizations, a news-writer, and captain of the England National Highlander team on 3 occasions. She has organised various tournaments including the EU vs NA Highlander showmatches and [[TeamFortress.TV]] Highlander invitational. The ex-[[ETF2L]] admin formed Highpander after playing for American teams in UGC North America and is currently one of the most experienced players in ETF2L today.

=== 6v6 ===
Hildreth started playing 6v6 in 2009, creating LagTastic Gaming to play in Division 6 of ETF2L during Season 7. She would stay on the team until January 2012, where she would then try his luck on The Devils Rejects, only to be kicked from the team within a month. She then formed [[Lowpander]], known originally as Furbo Pandas who would climb from Division 2 to Premiership level over the next 4 seasons, beating Last Man Standing in the Season 15 relegation playoff. After being sponsored by [[Decerto]], his team managed a 7th placed finish, retaining their Premiership spot. The team did however fold at the end of [[ETF2L 6v6 Season 16|ETF2L Season 16]], only to reform during [[ETF2L 6v6 Season 18|ETF2L Season 18]] with new players from Highlander. They managed another 7th placed finish, retaining their Premiership spot again after winning the relegation playoff once again. The team then folded after a poor start to the next season, Hildreth has since taken a break from 6v6 playing briefly for [[Team Colonslash]] before joining [[Hello Kitteh Ninjas!]] and helping them to a 1st place finish in High during Season 21. 
Later on, Hildreth played for Team Infomax during [[Gamers Assembly 2016]] and reformed [[Lowpander]] for [[ETF2L 6v6 Season 23|ETF2L Season 23]]. The team went on to win [[ETF2L 6v6 Season 25/High|ETF2L Season 25 High Playoffs]]; defeating 2nd and 1st seed teams and subsequently booking themselves a Premiership spot for [[ETF2L 6v6 Season 26/Premiership|ETF2L Season 26]]. 
In January 2017 she competed at the North American LAN [[Esports Arena Rewind 2017/Open|Esports Arena Rewind 2017]] with [[The Enigma Zone Crew]] in the open tournament.

=== Highlander ===
She started his European highlander journey at '''LagTastic Gaming Highlander''' in the [[ETF2L Highlander Community Challenge]], though she spent most of the tournament mercing for this American team, [[Lazytown Regulars]]. After this, she went on to join Unbelievably Brave Sweethearts, who were formed from the remains of Lazytown Regulars and played in North American Highlander in [[UGC]]. After finishing both top 8 and 4th on two occasions with uBs, Hildreth joined the new super team The Syndicate as a backup in season 8, who went on to win the UGC Platinum title. During Season 9 Hildreth was moved up to a main spot on Medic, however the majority of the title winning side had changed and The Syndicate finished in 4th place.
With this experience under his belt, she kept quiet in the lower divisions, until she brought her [[UGC]] team to Europe. [[Unbelievably Brave Sweethearts]] did well in [[ETF2L]], but eventually fell short to make the climb to the Premiership division, finishing in 3rd place during Season 4 of ETF2L.

After Season 4, she then began creating [[Highpander]] together with [[stevepander]] and would eventually win the Premiership in Season 6, beating [[itsallgood]] in the finals. The team has been in the top 3 of every season since it's formation and are known as one of the best Highlander teams in Europe currently.

==Trivia==
*According to stabbystabby, [[hildreth]] is a fan of cheese sandwiches.
*Hildreth is the owner of a Community Stickybomb Launcher, awarded to individuals who have made significant, valuable contributions to the Team Fortress 2 community.

==Latest Tournament Matches==
{{Player matches table}}

Insomnia61

2017-08-10T01:26:01Z

81.147.69.112: /* Invite Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=$5,000,000
|date =
|sdate = 2016-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Wembley Arena, London, England from the 26th to the 29th of August 2017. A $5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEpic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=jp
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===
* {{flag|fi}} [https://www.twitch.tv/puoskaritf Puoskari]
* {{flag|uk}} [http://comp.tf/wiki/Relic Jim Vickers]

===Highlights===
* {{flag|uk}} [http://comp.tf/wiki/Jim_Vickers Jim_Vickers_Rated_This_5_out_of_5_Jims]

== References ==
{{reflist}}

Silentes

2017-08-10T01:24:08Z

81.147.69.112:

Silentes

2017-08-09T22:18:05Z

81.147.69.112:

{{TabsHeader
|name1=Overview |link1={{PAGENAME}}
|name2=Results |link2={{PAGENAME}}/Results
|This=1
}}

{{NewInfobox Player
|id=Silentes
|image=Silentes.jpg
|caption=
|name=
|romanized_name=
|birth_date= 
|death_date=
|country=Japan
|status=Active
|years_active=2011 - ''Present''
|team=
|team2=
|role=Soldier
|role2=
|format=6v6
|sponsor=
|ids=nyeh, Sil
|nicknames= Weeaboo
|tftv=Silentes
|esea=
|etf2l=55082
|ozfortress=
|ozfcitadel=
|site=
|steam=76561197999595616
|twitch=fistmesondisama
|stream=
|youtube=SILENTESLOL
|twitter=
|snapchat=
|facebook=
|gplus=
|vk=
|fanclub=
|playlist=
|1stplace=
|2ndplace=
|3rdplace=
|4thplace=
|etf2lawards=
|ozfawards=
|team_history={{TH|2012 - 2013 |BigBluntGaming|no-link=true}}
{{TH|2013 - 2013 |Love Without Wings|no-link=true}}
{{TH|2014 - 2014 |Hello Kitteh Ninjas!}}
{{TH|2015 - 2016 |Full Tilt}}
{{TH|2016 - 2016 |Perilous Gaming}}
{{TH|2016 - 2016 |Full Tilt}}
{{TH|2016 - 2016 |Thanks Nursey}}
{{TH|2017 - 2017 |Loli Squad}}
{{TH|2017 - Present |ChampGG.K!}}
|retired=
|prize_money= 
}}

[[File:Lafcadio Hearn portrait.jpg|right|thumb|[[Lafcadio Hearn]], {{aka}} Koizumi Yakumo, a notable Irish-Greek international scholar and author well known for his strong interest in Japanese culture.]]

'''Japanophilia''' refers to the appreciation and love of Japanese culture, people or history.<ref>{{cite encyclopedia|title=Japanophile|encyclopedia=Webster's Third New International Dictionary, Unabridged|year=200|publisher= Merriam-Webster|quote= one who especially admires and likes Japan or Japanese ways|url=http://unabridged.merriam-webster.com|accessdate=2016-02-21}}</ref> In Japanese, the term for Japanophile is {{nihongo|"shinnichi"|親日}}, with "親" {{nihongo|"shin"|しん}} equivalent to the English prefix 'pro-', and "日" {{nihongo|"nichi"|にち}}, meaning "Japanese" (as in the word for Japan {{nihongo|"Nihon"|日本}}). The term was first used as early as the 18th century, switching in scope over time.

==History==

===Early usage===

The term "Japanophile" traces back to the late 18th and early 19th centuries before Japan became more open to foreign trade. [[Carl Peter Thunberg]] and [[Philipp Franz von Siebold]] helped introduce Japanese flora, artworks, and other objects to Europe which spiked interest.<ref>{{cite book|title=William and Henry Walters, the Reticent Collectors|author=William R. Johnston|year=1999|publisher=JHU Press|isbn=0-8018-6040-7|page=76}}</ref><ref>{{cite book|title=Topsy-Turvy 1585|author=Robin D. Gill|year=2004|publisher=Paraverse Press|isbn=0-9742618-1-5|page=25}}</ref> [[Lafcadio Hearn]], an Irish-Greek author who made his home in Japan in the 19th century, was described as "a confirmed Japanophile" by [[Tuttle Publishing|Charles E. Tuttle Company]] in their forewords to several of his books.<ref>{{cite news|title=Lafcadio Hearn|first= Heather|last= Hale|newspaper=Japanfile, the Website of [[Kansai Time Out]] Magazine|date=September 1990|url= http://www.japanfile.com/modules/smartsection/item.php?itemid=139|archiveurl=https://web.archive.org/web/20160305210917/http://japanfile.com/modules/smartsection/item.php?itemid=139 |archivedate=2016-03-05 }}</ref> Others may include [[Jules Brunet]], a [[French Army]] officer who played a famous role in the Japanese [[Boshin War]].

===20th century===

In the first decade of the 20th century, several British writers lauded Japan. In 1904, for example, [[Beatrice Webb]] wrote that Japan was a "rising star of human self-control and enlightenment", praising the "innovating collectivism" of the Japanese, and the "uncanny" purposefulness and open-mindedness of its "enlightened professional elite." [[H. G. Wells]] similarly named the élite of his ''[[A Modern Utopia]]'' "samurai". In part this was a result of the decline of British industrial primacy, with Japan and Germany rising comparatively. Germany was seen as a threat close to hand, but Japan was seen as a potential ally. The British sought efficiency as the solution to issues of productivity, and after the publication of [[Alfred Stead]]'s 1906 book ''Great Japan: A Study of National Efficiency'', pundits in Britain looked to Japan for lessons. This interest however, ended with [[World War I]].<ref>{{cite book|title=Parallax Visions: Making Sense of American-East Asian Relations|author=Bruce Cumings
|chapter=Archaeology, Descent, Emergence: American Mythology and East Asian Reality|year=1999|publisher=Duke University Press|isbn=0-8223-2924-7|page=25}}</ref>

[[General officer|General]] [[José Millán-Astray]], the founder of the [[Spanish Legion]], stated that the [[samurai]] warrior code [[Bushido]] exerted a great influence on him. Defining Bushido as "a perfect creed", Millán-Astray said that "the Spanish legionnaire is also a samurai and practices the Bushido essentials: Honor, Valor, Loyalty, Generosity, and Spirit of sacrifice", and added that [[Spain]] would become a great power like Japan by adhering to the code's principles.<ref>{{cite book |last=Jensen |first=Geoffrey |date=2002 |title=Irrational Triumph: Cultural Despair, Military Nationalism, and the Ideological Origins of Franco's Spain |url=https://books.google.com/books?id=XJRO8XheXvsC |location=[[Reno, Nevada]] |publisher=[[University of Nevada Press]] |page=150 |isbn=0874174813 |author-link= }}</ref> He also made a Spanish translation of [[Inazo Nitobe]]'s book [[Bushido: The Soul of Japan]] and a prologue to it.<ref>{{cite web |url=https://ddd.uab.cat/pub/artpub/2009/138541/meta_a2009v54n2p218.pdf |title=Millán-Astray’s Translation of Nitobe’s Bushido: The Soul of Japan |last=Beeby |first=Allison |last2=Rodríguez |first2=María Teresa |date=2009 |website=[[Autonomous University of Barcelona]] |access-date=6 June 2017}}</ref>

===21st century===
{{further|Anime and manga fandom}}
In the early 2000s, derogatory slang terms were created to demean those who appreciated [[Japanese popular culture]]. The term ''wapanese'' (from ''white Japanese'', or possibly also ''wannabe Japanese'') first came out in 2002 as a term used to describe a white person who is obsessed with Japanese culture, which includes [[anime]] and [[manga]]. The term ''weeaboo'' (or ''weeb'' later, compare ''[[wikt:dweeb|dweeb]]'') came from a comic strip created by [[Nicholas Gurewitch]] in which the term had no meaning other than it was something unpleasant.<ref>{{cite web|url=http://www.japanpowered.com/otaku-culture/am-i-a-weeaboo-what-does-weeaboo-mean-anyway|title=Am I a Weeaboo? What does Weeaboo Mean Anyway?|publisher=Japan Powered|author=Chris Kincaid|date=2015-08-30|accessdate=2016-02-21}}</ref> According to an unpublished MA thesis, [[4chan]] quickly picked up the word, and applied it in an abusive way in place of the already existing wapanese term.<ref>{{cite web|last=Davis|first=Jesse Christian|title=Japanese animation in America and its fans|url=http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/8736/thesis.pdf|accessdate=12 December 2015}}</ref>

It is debatable whether ''weeaboo'' has the same meaning as the Japanese term ''[[otaku]]'' (people with obsessive interests) as ''weeaboo'' has been used as a [[blanket term]] that implies a connection. ''Frog-kun'' from [[Crunchyroll]] states that the meaning of the word ''Otaku'' is hindered by [[cultural appropriation]], and that some [[Western culture|westerners]] believe that it can only be used to describe a Japanese person.<ref>{{cite web|url=http://www.crunchyroll.com/anime-feature/2016/08/22/feature-found-in-translation-the-evolution-of-the-word-otaku-part-1|title=FEATURE: Found in Translation - The Evolution of the Word “Otaku” [PART 1]|publisher=[[Crunchyroll]]|author=Frog-kun|date=August 22, 2016|accessdate=August 26, 2016}}</ref> In a blog post on [[Anime News Network]], Justin Sevakis gives a difference between the two, saying that there is nothing wrong with loving Japanese culture. He points out that a person only becomes a ''weeaboo'' when they start to be obnoxious, immature, and ignorant about the culture they love.<ref>{{cite web|url=http://www.animenewsnetwork.com/answerman/2014-08-22/.77818|title=Nobody Loves the Weeaboo|publisher=[[Anime News Network]]|author=Justin Sevakis|date=August 22, 2014|accessdate=March 10, 2016}}</ref> Matt Jardin from the [[Alaska Dispatch]] gave an opinion on the definition saying that weeaboos blindly prefer things from Japan while looking down on anything else despite obvious merit.<ref>{{cite web|url=https://www.adn.com/arts/2016/09/29/going-to-senshi-con-here-are-5-terms-you-need-to-know/|title=Going to Senshi Con this weekend? Here are 5 terms to know.|work=[[Alaska Dispatch]]|author=Matt Jardin|date=September 29, 2016|accessdate=May 18, 2017}}</ref> Rocket News 24 did a number of interviews with Japanese citizens asking them what they thought of "weeaboos". A "general consensus" was that they felt that any foreign interest in Japan was a good thing, and that ignorance might over time become understanding of their culture.<ref>{{cite web|url=http://en.rocketnews24.com/2016/04/07/what-do-japanese-people-think-of-weeaboos%E3%80%90video%E3%80%91/|title=What do Japanese people think of “weeaboos”?【Video】|publisher=Rocket News 24|author=evie lund|date=Apr 7, 2016|accessdate=May 30, 2016}}</ref><ref>{{cite web|url=http://en.rocketnews24.com/2016/04/21/japanese-people-react-to-weeaboo-cringe-videos-on-youtube/|title=Japanese people react to “weeaboo cringe videos” on YouTube【Video】|publisher=Rocket News 24|author=evie lund|date=Apr 21, 2016|accessdate=May 30, 2016}}</ref>

==See also==
{{Portal|Japan}}
* [[Japanization]]
* [[Japanification]]: cultural assimilation into Japanese society
* [[Japonism]]
* [[Japanese studies]]
* [[Cool Japan]]
* [[Japan Expo]]
* [[Anime and manga fandom]]
* [[Anime club]]
* [[Sinophile]]
* [[Korean Wave]]
* [[Taiwanese Wave]]

==References==
{{Reflist}}

{{Cultural appreciation}}

[[Category:Japanese culture]]
[[Category:Japan in non-Japanese culture]]
[[Category:Admiration of foreign cultures]]
[[Category:Japanese subcultures]]
[[Category:Asian culture]]
[[Category:Orientalism by type]]
[[Category:Japanese nationalism]]

==Latest Tournament Matches==
{{Player matches table|2}}

Silentes

2017-08-09T21:59:08Z

81.147.69.112:

{{TabsHeader
|name1=Overview |link1={{PAGENAME}}
|name2=Results |link2={{PAGENAME}}/Results
|This=1
}}

{{NewInfobox Player
|id=Silentes
|image=Silentes.jpg
|caption=
|name=
|romanized_name=
|birth_date= 
|death_date=
|country=Japan
|status=Active
|years_active=2011 - ''Present''
|team=
|team2=
|role=Soldier
|role2=
|format=6v6
|sponsor=
|ids=nyeh, Sil
|nicknames= Weeaboo Trash
|tftv=Silentes
|esea=
|etf2l=55082
|ozfortress=
|ozfcitadel=
|site=
|steam=76561197999595616
|twitch=fistmesondisama
|stream=
|youtube=SILENTESLOL
|twitter=
|snapchat=
|facebook=
|gplus=
|vk=
|fanclub=
|playlist=
|1stplace=
|2ndplace=
|3rdplace=
|4thplace=
|etf2lawards=
|ozfawards=
|team_history={{TH|2012 - 2013 |BigBluntGaming|no-link=true}}
{{TH|2013 - 2013 |Love Without Wings|no-link=true}}
{{TH|2014 - 2014 |Hello Kitteh Ninjas!}}
{{TH|2015 - 2016 |Full Tilt}}
{{TH|2016 - 2016 |Perilous Gaming}}
{{TH|2016 - 2016 |Full Tilt}}
{{TH|2016 - 2016 |Thanks Nursey}}
{{TH|2017 - 2017 |Loli Squad}}
{{TH|2017 - Present |ChampGG.K!}}
|retired=
|prize_money= 
}}

[[File:Lafcadio Hearn portrait.jpg|right|thumb|[[Lafcadio Hearn]], {{aka}} Koizumi Yakumo, a notable Irish-Greek international scholar and author well known for his strong interest in Japanese culture.]]

'''Japanophilia''' refers to the appreciation and love of Japanese culture, people or history.<ref>{{cite encyclopedia|title=Japanophile|encyclopedia=Webster's Third New International Dictionary, Unabridged|year=200|publisher= Merriam-Webster|quote= one who especially admires and likes Japan or Japanese ways|url=http://unabridged.merriam-webster.com|accessdate=2016-02-21}}</ref> In Japanese, the term for Japanophile is {{nihongo|"shinnichi"|親日}}, with "親" {{nihongo|"shin"|しん}} equivalent to the English prefix 'pro-', and "日" {{nihongo|"nichi"|にち}}, meaning "Japanese" (as in the word for Japan {{nihongo|"Nihon"|日本}}). The term was first used as early as the 18th century, switching in scope over time.

==History==

===Early usage===

The term "Japanophile" traces back to the late 18th and early 19th centuries before Japan became more open to foreign trade. [[Carl Peter Thunberg]] and [[Philipp Franz von Siebold]] helped introduce Japanese flora, artworks, and other objects to Europe which spiked interest.<ref>{{cite book|title=William and Henry Walters, the Reticent Collectors|author=William R. Johnston|year=1999|publisher=JHU Press|isbn=0-8018-6040-7|page=76}}</ref><ref>{{cite book|title=Topsy-Turvy 1585|author=Robin D. Gill|year=2004|publisher=Paraverse Press|isbn=0-9742618-1-5|page=25}}</ref> [[Lafcadio Hearn]], an Irish-Greek author who made his home in Japan in the 19th century, was described as "a confirmed Japanophile" by [[Tuttle Publishing|Charles E. Tuttle Company]] in their forewords to several of his books.<ref>{{cite news|title=Lafcadio Hearn|first= Heather|last= Hale|newspaper=Japanfile, the Website of [[Kansai Time Out]] Magazine|date=September 1990|url= http://www.japanfile.com/modules/smartsection/item.php?itemid=139|archiveurl=https://web.archive.org/web/20160305210917/http://japanfile.com/modules/smartsection/item.php?itemid=139 |archivedate=2016-03-05 }}</ref> Others may include [[Jules Brunet]], a [[French Army]] officer who played a famous role in the Japanese [[Boshin War]].

===20th century===

In the first decade of the 20th century, several British writers lauded Japan. In 1904, for example, [[Beatrice Webb]] wrote that Japan was a "rising star of human self-control and enlightenment", praising the "innovating collectivism" of the Japanese, and the "uncanny" purposefulness and open-mindedness of its "enlightened professional elite." [[H. G. Wells]] similarly named the élite of his ''[[A Modern Utopia]]'' "samurai". In part this was a result of the decline of British industrial primacy, with Japan and Germany rising comparatively. Germany was seen as a threat close to hand, but Japan was seen as a potential ally. The British sought efficiency as the solution to issues of productivity, and after the publication of [[Alfred Stead]]'s 1906 book ''Great Japan: A Study of National Efficiency'', pundits in Britain looked to Japan for lessons. This interest however, ended with [[World War I]].<ref>{{cite book|title=Parallax Visions: Making Sense of American-East Asian Relations|author=Bruce Cumings
|chapter=Archaeology, Descent, Emergence: American Mythology and East Asian Reality|year=1999|publisher=Duke University Press|isbn=0-8223-2924-7|page=25}}</ref>

[[General officer|General]] [[José Millán-Astray]], the founder of the [[Spanish Legion]], stated that the [[samurai]] warrior code [[Bushido]] exerted a great influence on him. Defining Bushido as "a perfect creed", Millán-Astray said that "the Spanish legionnaire is also a samurai and practices the Bushido essentials: Honor, Valor, Loyalty, Generosity, and Spirit of sacrifice", and added that [[Spain]] would become a great power like Japan by adhering to the code's principles.<ref>{{cite book |last=Jensen |first=Geoffrey |date=2002 |title=Irrational Triumph: Cultural Despair, Military Nationalism, and the Ideological Origins of Franco's Spain |url=https://books.google.com/books?id=XJRO8XheXvsC |location=[[Reno, Nevada]] |publisher=[[University of Nevada Press]] |page=150 |isbn=0874174813 |author-link= }}</ref> He also made a Spanish translation of [[Inazo Nitobe]]'s book [[Bushido: The Soul of Japan]] and a prologue to it.<ref>{{cite web |url=https://ddd.uab.cat/pub/artpub/2009/138541/meta_a2009v54n2p218.pdf |title=Millán-Astray’s Translation of Nitobe’s Bushido: The Soul of Japan |last=Beeby |first=Allison |last2=Rodríguez |first2=María Teresa |date=2009 |website=[[Autonomous University of Barcelona]] |access-date=6 June 2017}}</ref>

===21st century===
{{further|Anime and manga fandom}}
In the early 2000s, derogatory slang terms were created to demean those who appreciated [[Japanese popular culture]]. The term ''wapanese'' (from ''white Japanese'', or possibly also ''wannabe Japanese'') first came out in 2002 as a term used to describe a white person who is obsessed with Japanese culture, which includes [[anime]] and [[manga]]. The term ''weeaboo'' (or ''weeb'' later, compare ''[[wikt:dweeb|dweeb]]'') came from a comic strip created by [[Nicholas Gurewitch]] in which the term had no meaning other than it was something unpleasant.<ref>{{cite web|url=http://www.japanpowered.com/otaku-culture/am-i-a-weeaboo-what-does-weeaboo-mean-anyway|title=Am I a Weeaboo? What does Weeaboo Mean Anyway?|publisher=Japan Powered|author=Chris Kincaid|date=2015-08-30|accessdate=2016-02-21}}</ref> According to an unpublished MA thesis, [[4chan]] quickly picked up the word, and applied it in an abusive way in place of the already existing wapanese term.<ref>{{cite web|last=Davis|first=Jesse Christian|title=Japanese animation in America and its fans|url=http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/8736/thesis.pdf|accessdate=12 December 2015}}</ref>

It is debatable whether ''weeaboo'' has the same meaning as the Japanese term ''[[otaku]]'' (people with obsessive interests) as ''weeaboo'' has been used as a [[blanket term]] that implies a connection. ''Frog-kun'' from [[Crunchyroll]] states that the meaning of the word ''Otaku'' is hindered by [[cultural appropriation]], and that some [[Western culture|westerners]] believe that it can only be used to describe a Japanese person.<ref>{{cite web|url=http://www.crunchyroll.com/anime-feature/2016/08/22/feature-found-in-translation-the-evolution-of-the-word-otaku-part-1|title=FEATURE: Found in Translation - The Evolution of the Word “Otaku” [PART 1]|publisher=[[Crunchyroll]]|author=Frog-kun|date=August 22, 2016|accessdate=August 26, 2016}}</ref> In a blog post on [[Anime News Network]], Justin Sevakis gives a difference between the two, saying that there is nothing wrong with loving Japanese culture. He points out that a person only becomes a ''weeaboo'' when they start to be obnoxious, immature, and ignorant about the culture they love.<ref>{{cite web|url=http://www.animenewsnetwork.com/answerman/2014-08-22/.77818|title=Nobody Loves the Weeaboo|publisher=[[Anime News Network]]|author=Justin Sevakis|date=August 22, 2014|accessdate=March 10, 2016}}</ref> Matt Jardin from the [[Alaska Dispatch]] gave an opinion on the definition saying that weeaboos blindly prefer things from Japan while looking down on anything else despite obvious merit.<ref>{{cite web|url=https://www.adn.com/arts/2016/09/29/going-to-senshi-con-here-are-5-terms-you-need-to-know/|title=Going to Senshi Con this weekend? Here are 5 terms to know.|work=[[Alaska Dispatch]]|author=Matt Jardin|date=September 29, 2016|accessdate=May 18, 2017}}</ref> Rocket News 24 did a number of interviews with Japanese citizens asking them what they thought of "weeaboos". A "general consensus" was that they felt that any foreign interest in Japan was a good thing, and that ignorance might over time become understanding of their culture.<ref>{{cite web|url=http://en.rocketnews24.com/2016/04/07/what-do-japanese-people-think-of-weeaboos%E3%80%90video%E3%80%91/|title=What do Japanese people think of “weeaboos”?【Video】|publisher=Rocket News 24|author=evie lund|date=Apr 7, 2016|accessdate=May 30, 2016}}</ref><ref>{{cite web|url=http://en.rocketnews24.com/2016/04/21/japanese-people-react-to-weeaboo-cringe-videos-on-youtube/|title=Japanese people react to “weeaboo cringe videos” on YouTube【Video】|publisher=Rocket News 24|author=evie lund|date=Apr 21, 2016|accessdate=May 30, 2016}}</ref>

==See also==
{{Portal|Japan}}
* [[Japanization]]
* [[Japanification]]: cultural assimilation into Japanese society
* [[Japonism]]
* [[Japanese studies]]
* [[Cool Japan]]
* [[Japan Expo]]
* [[Anime and manga fandom]]
* [[Anime club]]
* [[Sinophile]]
* [[Korean Wave]]
* [[Taiwanese Wave]]

==References==
{{Reflist}}

{{Cultural appreciation}}

[[Category:Japanese culture]]
[[Category:Japan in non-Japanese culture]]
[[Category:Admiration of foreign cultures]]
[[Category:Japanese subcultures]]
[[Category:Asian culture]]
[[Category:Orientalism by type]]
[[Category:Japanese nationalism]]

==Latest Tournament Matches==
{{Player matches table|2}}

Silentes

2017-08-09T21:58:42Z

81.147.69.112: Undo revision 54244 by 81.147.69.112 (talk)

Silentes

2017-08-09T21:57:39Z

81.147.69.112:

[[File:Lafcadio Hearn portrait.jpg|right|thumb|[[Lafcadio Hearn]], {{aka}} Koizumi Yakumo, a notable Irish-Greek international scholar and author well known for his strong interest in Japanese culture.]]

'''Japanophilia''' refers to the appreciation and love of Japanese culture, people or history.<ref>{{cite encyclopedia|title=Japanophile|encyclopedia=Webster's Third New International Dictionary, Unabridged|year=200|publisher= Merriam-Webster|quote= one who especially admires and likes Japan or Japanese ways|url=http://unabridged.merriam-webster.com|accessdate=2016-02-21}}</ref> In Japanese, the term for Japanophile is {{nihongo|"shinnichi"|親日}}, with "親" {{nihongo|"shin"|しん}} equivalent to the English prefix 'pro-', and "日" {{nihongo|"nichi"|にち}}, meaning "Japanese" (as in the word for Japan {{nihongo|"Nihon"|日本}}). The term was first used as early as the 18th century, switching in scope over time.

==History==

===Early usage===

The term "Japanophile" traces back to the late 18th and early 19th centuries before Japan became more open to foreign trade. [[Carl Peter Thunberg]] and [[Philipp Franz von Siebold]] helped introduce Japanese flora, artworks, and other objects to Europe which spiked interest.<ref>{{cite book|title=William and Henry Walters, the Reticent Collectors|author=William R. Johnston|year=1999|publisher=JHU Press|isbn=0-8018-6040-7|page=76}}</ref><ref>{{cite book|title=Topsy-Turvy 1585|author=Robin D. Gill|year=2004|publisher=Paraverse Press|isbn=0-9742618-1-5|page=25}}</ref> [[Lafcadio Hearn]], an Irish-Greek author who made his home in Japan in the 19th century, was described as "a confirmed Japanophile" by [[Tuttle Publishing|Charles E. Tuttle Company]] in their forewords to several of his books.<ref>{{cite news|title=Lafcadio Hearn|first= Heather|last= Hale|newspaper=Japanfile, the Website of [[Kansai Time Out]] Magazine|date=September 1990|url= http://www.japanfile.com/modules/smartsection/item.php?itemid=139|archiveurl=https://web.archive.org/web/20160305210917/http://japanfile.com/modules/smartsection/item.php?itemid=139 |archivedate=2016-03-05 }}</ref> Others may include [[Jules Brunet]], a [[French Army]] officer who played a famous role in the Japanese [[Boshin War]].

===20th century===

In the first decade of the 20th century, several British writers lauded Japan. In 1904, for example, [[Beatrice Webb]] wrote that Japan was a "rising star of human self-control and enlightenment", praising the "innovating collectivism" of the Japanese, and the "uncanny" purposefulness and open-mindedness of its "enlightened professional elite." [[H. G. Wells]] similarly named the élite of his ''[[A Modern Utopia]]'' "samurai". In part this was a result of the decline of British industrial primacy, with Japan and Germany rising comparatively. Germany was seen as a threat close to hand, but Japan was seen as a potential ally. The British sought efficiency as the solution to issues of productivity, and after the publication of [[Alfred Stead]]'s 1906 book ''Great Japan: A Study of National Efficiency'', pundits in Britain looked to Japan for lessons. This interest however, ended with [[World War I]].<ref>{{cite book|title=Parallax Visions: Making Sense of American-East Asian Relations|author=Bruce Cumings
|chapter=Archaeology, Descent, Emergence: American Mythology and East Asian Reality|year=1999|publisher=Duke University Press|isbn=0-8223-2924-7|page=25}}</ref>

[[General officer|General]] [[José Millán-Astray]], the founder of the [[Spanish Legion]], stated that the [[samurai]] warrior code [[Bushido]] exerted a great influence on him. Defining Bushido as "a perfect creed", Millán-Astray said that "the Spanish legionnaire is also a samurai and practices the Bushido essentials: Honor, Valor, Loyalty, Generosity, and Spirit of sacrifice", and added that [[Spain]] would become a great power like Japan by adhering to the code's principles.<ref>{{cite book |last=Jensen |first=Geoffrey |date=2002 |title=Irrational Triumph: Cultural Despair, Military Nationalism, and the Ideological Origins of Franco's Spain |url=https://books.google.com/books?id=XJRO8XheXvsC |location=[[Reno, Nevada]] |publisher=[[University of Nevada Press]] |page=150 |isbn=0874174813 |author-link= }}</ref> He also made a Spanish translation of [[Inazo Nitobe]]'s book [[Bushido: The Soul of Japan]] and a prologue to it.<ref>{{cite web |url=https://ddd.uab.cat/pub/artpub/2009/138541/meta_a2009v54n2p218.pdf |title=Millán-Astray’s Translation of Nitobe’s Bushido: The Soul of Japan |last=Beeby |first=Allison |last2=Rodríguez |first2=María Teresa |date=2009 |website=[[Autonomous University of Barcelona]] |access-date=6 June 2017}}</ref>

===21st century===
{{further|Anime and manga fandom}}
In the early 2000s, derogatory slang terms were created to demean those who appreciated [[Japanese popular culture]]. The term ''wapanese'' (from ''white Japanese'', or possibly also ''wannabe Japanese'') first came out in 2002 as a term used to describe a white person who is obsessed with Japanese culture, which includes [[anime]] and [[manga]]. The term ''weeaboo'' (or ''weeb'' later, compare ''[[wikt:dweeb|dweeb]]'') came from a comic strip created by [[Nicholas Gurewitch]] in which the term had no meaning other than it was something unpleasant.<ref>{{cite web|url=http://www.japanpowered.com/otaku-culture/am-i-a-weeaboo-what-does-weeaboo-mean-anyway|title=Am I a Weeaboo? What does Weeaboo Mean Anyway?|publisher=Japan Powered|author=Chris Kincaid|date=2015-08-30|accessdate=2016-02-21}}</ref> According to an unpublished MA thesis, [[4chan]] quickly picked up the word, and applied it in an abusive way in place of the already existing wapanese term.<ref>{{cite web|last=Davis|first=Jesse Christian|title=Japanese animation in America and its fans|url=http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/8736/thesis.pdf|accessdate=12 December 2015}}</ref>

It is debatable whether ''weeaboo'' has the same meaning as the Japanese term ''[[otaku]]'' (people with obsessive interests) as ''weeaboo'' has been used as a [[blanket term]] that implies a connection. ''Frog-kun'' from [[Crunchyroll]] states that the meaning of the word ''Otaku'' is hindered by [[cultural appropriation]], and that some [[Western culture|westerners]] believe that it can only be used to describe a Japanese person.<ref>{{cite web|url=http://www.crunchyroll.com/anime-feature/2016/08/22/feature-found-in-translation-the-evolution-of-the-word-otaku-part-1|title=FEATURE: Found in Translation - The Evolution of the Word “Otaku” [PART 1]|publisher=[[Crunchyroll]]|author=Frog-kun|date=August 22, 2016|accessdate=August 26, 2016}}</ref> In a blog post on [[Anime News Network]], Justin Sevakis gives a difference between the two, saying that there is nothing wrong with loving Japanese culture. He points out that a person only becomes a ''weeaboo'' when they start to be obnoxious, immature, and ignorant about the culture they love.<ref>{{cite web|url=http://www.animenewsnetwork.com/answerman/2014-08-22/.77818|title=Nobody Loves the Weeaboo|publisher=[[Anime News Network]]|author=Justin Sevakis|date=August 22, 2014|accessdate=March 10, 2016}}</ref> Matt Jardin from the [[Alaska Dispatch]] gave an opinion on the definition saying that weeaboos blindly prefer things from Japan while looking down on anything else despite obvious merit.<ref>{{cite web|url=https://www.adn.com/arts/2016/09/29/going-to-senshi-con-here-are-5-terms-you-need-to-know/|title=Going to Senshi Con this weekend? Here are 5 terms to know.|work=[[Alaska Dispatch]]|author=Matt Jardin|date=September 29, 2016|accessdate=May 18, 2017}}</ref> Rocket News 24 did a number of interviews with Japanese citizens asking them what they thought of "weeaboos". A "general consensus" was that they felt that any foreign interest in Japan was a good thing, and that ignorance might over time become understanding of their culture.<ref>{{cite web|url=http://en.rocketnews24.com/2016/04/07/what-do-japanese-people-think-of-weeaboos%E3%80%90video%E3%80%91/|title=What do Japanese people think of “weeaboos”?【Video】|publisher=Rocket News 24|author=evie lund|date=Apr 7, 2016|accessdate=May 30, 2016}}</ref><ref>{{cite web|url=http://en.rocketnews24.com/2016/04/21/japanese-people-react-to-weeaboo-cringe-videos-on-youtube/|title=Japanese people react to “weeaboo cringe videos” on YouTube【Video】|publisher=Rocket News 24|author=evie lund|date=Apr 21, 2016|accessdate=May 30, 2016}}</ref>

==See also==
{{Portal|Japan}}
* [[Japanization]]
* [[Japanification]]: cultural assimilation into Japanese society
* [[Japonism]]
* [[Japanese studies]]
* [[Cool Japan]]
* [[Japan Expo]]
* [[Anime and manga fandom]]
* [[Anime club]]
* [[Sinophile]]
* [[Korean Wave]]
* [[Taiwanese Wave]]

==References==
{{Reflist}}

{{Cultural appreciation}}

[[Category:Japanese culture]]
[[Category:Japan in non-Japanese culture]]
[[Category:Admiration of foreign cultures]]
[[Category:Japanese subcultures]]
[[Category:Asian culture]]
[[Category:Orientalism by type]]
[[Category:Japanese nationalism]]

Spy

2017-08-09T21:53:27Z

81.147.69.112:

[[File:SpyIcon.png|200px|right||link=http://wiki.teamfortress.com/wiki/the SPY!!!!1!']]
The '''the SPY!!!!1!''' is a suave backstabbing rogue that has the ability to insta-kill any class if they backstab someone with their knife. the SPIES!!!!1! are valued in that they can position themselves as they see fit with their Cloak and can get important [[Glossary#Metagame terms|Picks]] through the manipulation and deception of the enemy team. the SPY!!!!1! arguably has below average direct combat ability, as he is solely designed to only get one or two kills at a time. As a pick class, the the SPY!!!!1! will usually target the enemy [[Demoman]], [[Heavy]] or [[Medic]] and either get the Medic to pop or drop his [[ÜberCharge]]. the SPY!!!!1! is also capable of incapacitating and destroying the [[Engineer]]'s buildings.

==6v6==
{{main|the SPY!!!!1! (6v6)}}

In 6v6, the SPY!!!!1! is considered an [[offclass]] due to his unreliable damage output and weakness. If a the SPY!!!!1! is played he will usually only get one chance at getting a pick. Because of this, the the SPY!!!!1! is rarely used and will most often target the enemy Medic or Demoman to get a pick worth more than his own life. A team might use a the SPY!!!!1! when the enemy Medic has a large advantage, or to get an important pick over the enemy team and end a stalemate.

In terms of assassination power, the Spy!!!!1! has less potential than the Sniper, so be wary when running a the Spy!!!!1!. A Sniper can shoot multiple times and get multiple picks, but a the SPY!!!!1! will usually only get one chance for a pick and is almost certainly going to die after their attempt to pick someone. However, because the SPY!!!!1! is not often used in 6v6, players are generally less aware of the SPIES!!!!1!, making them more likely to fall for disguises and backstabs. the SPY!!!!1! is commonly used as a surprise tactic for breaking stalemates against teams too wary of [[Snipers]] or [[Roamer]] bombings. However the SPY!!!!1! is still largely situational and most teams will prefer a [[Sniper]].

There are benefits to running a the SPY!!!!1! however. You can check the enemy Medic's Uber percentage and choice of Medigun, call surprise offclasses and where the enemy is positioned. The Spy can also be utilised for backcapping due to his cloak allowing him to traverse the map easily and undisturbed.

==Highlander==

{{main|Spy (Highlander)}}

In Highlander, the SPY!!!!1! is used as a support class. He is often used to pick the enemy Medic, Heavy, Demoman, Sniper, Engineer, or any key targets that are giving his team trouble. the SPIES!!!!1! in Highlander must be aware that the enemy team has a full-time [[Pyro]] and is [[spychecking]] more often, leaving the SPY!!!!1!with less opportunities for picks.

the SPY!!!!1! is also the best scouting class in the game, providing invaluable information for his team. He can find how far along a [[Medic]] is to fully charging his ubercharge, where the enemy team is located, and in what direction they are moving towards in the safety provided by his watches.

==Techniques==
When spotted or confronted by an enemy, a the SPY!!!!1! is almost always put at a disadvantage, due to his low damage output on primaries. In times of need, the SPIES!!!!1! may need to use one of the many techniques developed to deceive or lure their enemies in position for a stab that otherwise wouldn't be possible. These are called [[trickstabs]] and are often a technique highly exploited by most of the high level the SPIES!!!!1!.

Some the SPY!!!!1! players may opt in to primarily use a gun, such as the [[Ambassador]], to snipe with. These players mainly stick behind their teams lines and focus on getting headshots to get kills. A good the SPY!!!!1! is said to be able to achieve Ambassador headshots and regular backstabs.

==Weapons==
=== Primary ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Revolver
|description = The '''Revolver''' deals a base damage of 40, with a clip of 6 rounds. This weapon is a perfect choice for Spies that prefer a constant damage-per-second take rather than a skill based damage increase.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Ambassador
|description = The '''Ambassador''' deals a base damage of 34, with a clip of 6 rounds. The Ambassador has the unique ability to take advantage of this accuracy with 102-damage head shots. After a short cool down that is shown visually by your cross hair size, headshots and perfect accuracy are achievable. No falloff damage on the headshot makes it great for sniping targets out of your standard range.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = L'Etranger
|description = The '''L'Etranger''' deals a base damage of 32, with a clip of 6 rounds. You will gain +40% cloak by having this weapon equipped. On every hit, the user gains an additional 15% cloak. Requiring full cloak to activate, the [[Dead Ringer]] can be an effective combo. It can also be used to somewhat cancel out the downsides of the [[Cloak and Dagger]].
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Enforcer
|description = The '''Enforcer''' deals a base damage of 48, with a clip of 6 rounds. It has -20% firing speed, and can not get random crits. The Enforcer is known for having the highest base damage of all revolvers with its damage boost of 20% when disguised.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Diamondback
|description = The '''Diamondback''' deals a base damage of 34 and cannot get random critical hits. For every Engineer building a Spy saps and for every backstab kill, he will get one free critical hit (102 damage) for his Diamondback. This can be useful for taking out weak classes that you couldn't otherwise attack. The crits should be carefully timed and placed on players who are busy fighting others and whom your team needs assistance fighting.
|ugc4s = true
|6s = true
|ugchl = false
|etf2lhl = false
}}
{{Class Weapon Table End}}

=== Secondary ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Sapper
|description = The '''Sapper''' is the Spy's tool for disabling and destroying enemy engineers buildings. The stock sapper will disable an enemy building when placed, but if an enemy engineer removes the sapper, the building will continue to operate. Therefore, a more effective way of sapping for Highlander is killing the engineer before sapping. A good time for this is usually with your teams uber or kritz push.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Red-Tape Recorder
|link = Red-Tape_Recorder
|description = Much like the stock sapper, the '''Red-Tape Recorder''' also disables enemy engineer's buildings. This sapper, however, does not destroy the buildings it saps, rather it reverses the construction of the building. It is banned in most leagues.
|ugc4s = false
|6s = true
|ugchl = false
|etf2lhl = false
}}
{{Class Weapon Table End}}

=== Melee ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Knife
|description = The '''Knife''' is the most powerful weapon in the Spy's arsenal. On backstab it does 6x the enemy's current health. When hitting anywhere else besides the back it does a base damage of 40 (also called butter-knifing). Spies have the capability of getting behind the enemy lines by means of cloaking and disguising, then using the knife to backstab enemies. Though the Knife is very powerful, players must not forget that they also have a gun.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Your Eternal Reward
|link = Your_Eternal_Reward
|description = Using '''Your Eternal Reward''' removes the Spy's ability to disguise with the disguise kit. The Spy can only disguise by successfully backstabbing an enemy. Upon backstab, the Spy will immediately disguise as the victim, the victim's body will disappear without noise, and the enemy team will receive no killfeed of their teammate dying. In the competitive scene, this knife holds controversy due to the fact that without a disguise it is near impossible to get the initial backstab, and that if one manages to get the intitial disguise, the victim will likely notify their team of the disguise making the next attempt even less likely.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = the SPY!!!!1!-cicle
|description = The '''the SPY!!!!1!-Cicle''' acts like "Pyro insurance" in that, when the the SPY!!!!1! is lit on fire, the the SPY!!!!1!-Cicle melts and allows the the SPY!!!!1! to become fireproof for a second and immune from afterburn for seven seconds. This is useful for keeping the Spy alive in order to find a better opportunity for a pick, but the the SPY!!!!1!-Cicle is melted and unusable for 15 seconds, although the time can be decreased by picking up ammo boxes. Backstabbed victims are turned into ice sculptures, revealing the Spy's presence. While possibly saving the user's life, game-winning backstab attempts can be foiled by the Pyro. Users should take their play-style as well as the current status of the round into consideration before choosing this knife over the stock knife. A run-away the SPY!!!!1! without a knife is as useless as a dead spy.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Conniver's Kunai
|link = Conniver's_Kunai
|description = When the '''Conniver's Kunai''' is equipped, the player starts out with 70 health. On backstab, the the SPY!!!!1! absorbs the victims health. The maximum health the Spy can reach is 210. Upon backstab flames can also be put out. The controversy behind this knife is whether or not starting out with 70 health is worth getting health later. It is often argued that the extra health upon a backstab does not have a significant chance of preventing death, but the reduced health before a backstab makes you significantly more likely to die to spam damage and random hits taken.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Big Earner
|link = Big_Earner
|description = Equipping this weapon reduces the max health of the user by 25, lowering the SPY!!!!1! overall health to 100. However, killing an enemy with this weapon, either with a backstab or regular melee attack, will fill the Cloak meter by 30%, regardless of which cloaking device is equipped, and increases the player walk speed for 3 seconds.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table End}}

=== PDA ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Invis Watch
|link = Invis_Watch
|description = The default '''Invis Watch''' for Spy is timed. It provides the Spy with 9 seconds of cloak time, during which he will have a 20% damage resistance. While cloaked or uncloaked a Spy can pick up ammo boxes as well as dropped weapons to refill the cloak meter. The Invis Watch is best suited for an aggressive play style, allowing for more picks. Watch out for enemies however because bumping into them will make you visible!
|ugc4s = always
|6s=always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Cloak and Dagger
|link = Cloak_and_Dagger
|description = The '''Cloak and Dagger''' is motion sensitive, which means that while a player isn't moving the cloak will build. This watch has a double cloak recharge rate as well as a 29% faster cloak drain rate. Also, this watch's cloak can not be replenished by ammo boxes or dropped weapons unless uncloaked. The Cloak and Dagger is best suited for a more passive play style, providing the player with the ability to wait and call important things like enemy combo positioning as well as Medic ubercharge. The Cloak and Dagger is often paired with the L'Etranger in order to make up for the reduced cloak time and the lack of a way to quickly regenerate cloak.
|ugc4s = true
|6s=true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Dead Ringer
|link = Dead_Ringer
|description = The '''Dead Ringer''' is unique among the Spy watches. Instead of cloaking the player when deployed, it is held in the players hand. While the Dead Ringer is out the player will not be able to attack, but the player takes reduced damage alongside with a 3 second speed boost. In addition, the player will go invisible and drop a dead body, therefore feigning death. The initial hit is reduced by 75%, and during the 3 seconds of feigning death, the spy will have a 65% damage resistance that will gradually decrease to 20%. Only for 3 seconds of the 7 seconds of cloak time the Dead Ringer provides, you will not become visible when bumping into players. The Dead Ringer is best suited for an even more aggressive play style than the Invis Watch, allowing you to get in your enemies face before feigning.
|ugc4s = true
|6s=true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table End}}

==See Also==
*[[Spy (6v6)]]
*[[Spy (Highlander)]]

==External Links==
[http://steamcommunity.com/sharedfiles/filedetails/?id=312421865# DarkNecrid's Comprehensive Pub & Competitive Spy Guide]

[[Category:Classes]]

Spy

2017-08-09T21:52:49Z

81.147.69.112:

[[File:SpyIcon.png|200px|right||link=http://wiki.teamfortress.com/wiki/Spy]]
The '''the SPY!!!!1!''' is a suave backstabbing rogue that has the ability to insta-kill any class if they backstab someone with their knife. the SPIES!!!!1! are valued in that they can position themselves as they see fit with their Cloak and can get important [[Glossary#Metagame terms|Picks]] through the manipulation and deception of the enemy team. the SPY!!!!1! arguably has below average direct combat ability, as he is solely designed to only get one or two kills at a time. As a pick class, the the SPY!!!!1! will usually target the enemy [[Demoman]], [[Heavy]] or [[Medic]] and either get the Medic to pop or drop his [[ÜberCharge]]. the SPY!!!!1! is also capable of incapacitating and destroying the [[Engineer]]'s buildings.

==6v6==
{{main|the SPY!!!!1! (6v6)}}

In 6v6, the SPY!!!!1! is considered an [[offclass]] due to his unreliable damage output and weakness. If a the SPY!!!!1! is played he will usually only get one chance at getting a pick. Because of this, the the SPY!!!!1! is rarely used and will most often target the enemy Medic or Demoman to get a pick worth more than his own life. A team might use a the SPY!!!!1! when the enemy Medic has a large advantage, or to get an important pick over the enemy team and end a stalemate.

In terms of assassination power, the Spy!!!!1! has less potential than the Sniper, so be wary when running a the Spy!!!!1!. A Sniper can shoot multiple times and get multiple picks, but a the SPY!!!!1! will usually only get one chance for a pick and is almost certainly going to die after their attempt to pick someone. However, because the SPY!!!!1! is not often used in 6v6, players are generally less aware of the SPIES!!!!1!, making them more likely to fall for disguises and backstabs. the SPY!!!!1! is commonly used as a surprise tactic for breaking stalemates against teams too wary of [[Snipers]] or [[Roamer]] bombings. However the SPY!!!!1! is still largely situational and most teams will prefer a [[Sniper]].

There are benefits to running a the SPY!!!!1! however. You can check the enemy Medic's Uber percentage and choice of Medigun, call surprise offclasses and where the enemy is positioned. The Spy can also be utilised for backcapping due to his cloak allowing him to traverse the map easily and undisturbed.

==Highlander==

{{main|Spy (Highlander)}}

In Highlander, the SPY!!!!1! is used as a support class. He is often used to pick the enemy Medic, Heavy, Demoman, Sniper, Engineer, or any key targets that are giving his team trouble. the SPIES!!!!1! in Highlander must be aware that the enemy team has a full-time [[Pyro]] and is [[spychecking]] more often, leaving the SPY!!!!1!with less opportunities for picks.

the SPY!!!!1! is also the best scouting class in the game, providing invaluable information for his team. He can find how far along a [[Medic]] is to fully charging his ubercharge, where the enemy team is located, and in what direction they are moving towards in the safety provided by his watches.

==Techniques==
When spotted or confronted by an enemy, a the SPY!!!!1! is almost always put at a disadvantage, due to his low damage output on primaries. In times of need, the SPIES!!!!1! may need to use one of the many techniques developed to deceive or lure their enemies in position for a stab that otherwise wouldn't be possible. These are called [[trickstabs]] and are often a technique highly exploited by most of the high level the SPIES!!!!1!.

Some the SPY!!!!1! players may opt in to primarily use a gun, such as the [[Ambassador]], to snipe with. These players mainly stick behind their teams lines and focus on getting headshots to get kills. A good the SPY!!!!1! is said to be able to achieve Ambassador headshots and regular backstabs.

==Weapons==
=== Primary ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Revolver
|description = The '''Revolver''' deals a base damage of 40, with a clip of 6 rounds. This weapon is a perfect choice for Spies that prefer a constant damage-per-second take rather than a skill based damage increase.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Ambassador
|description = The '''Ambassador''' deals a base damage of 34, with a clip of 6 rounds. The Ambassador has the unique ability to take advantage of this accuracy with 102-damage head shots. After a short cool down that is shown visually by your cross hair size, headshots and perfect accuracy are achievable. No falloff damage on the headshot makes it great for sniping targets out of your standard range.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = L'Etranger
|description = The '''L'Etranger''' deals a base damage of 32, with a clip of 6 rounds. You will gain +40% cloak by having this weapon equipped. On every hit, the user gains an additional 15% cloak. Requiring full cloak to activate, the [[Dead Ringer]] can be an effective combo. It can also be used to somewhat cancel out the downsides of the [[Cloak and Dagger]].
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Enforcer
|description = The '''Enforcer''' deals a base damage of 48, with a clip of 6 rounds. It has -20% firing speed, and can not get random crits. The Enforcer is known for having the highest base damage of all revolvers with its damage boost of 20% when disguised.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Diamondback
|description = The '''Diamondback''' deals a base damage of 34 and cannot get random critical hits. For every Engineer building a Spy saps and for every backstab kill, he will get one free critical hit (102 damage) for his Diamondback. This can be useful for taking out weak classes that you couldn't otherwise attack. The crits should be carefully timed and placed on players who are busy fighting others and whom your team needs assistance fighting.
|ugc4s = true
|6s = true
|ugchl = false
|etf2lhl = false
}}
{{Class Weapon Table End}}

=== Secondary ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Sapper
|description = The '''Sapper''' is the Spy's tool for disabling and destroying enemy engineers buildings. The stock sapper will disable an enemy building when placed, but if an enemy engineer removes the sapper, the building will continue to operate. Therefore, a more effective way of sapping for Highlander is killing the engineer before sapping. A good time for this is usually with your teams uber or kritz push.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Red-Tape Recorder
|link = Red-Tape_Recorder
|description = Much like the stock sapper, the '''Red-Tape Recorder''' also disables enemy engineer's buildings. This sapper, however, does not destroy the buildings it saps, rather it reverses the construction of the building. It is banned in most leagues.
|ugc4s = false
|6s = true
|ugchl = false
|etf2lhl = false
}}
{{Class Weapon Table End}}

=== Melee ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Knife
|description = The '''Knife''' is the most powerful weapon in the Spy's arsenal. On backstab it does 6x the enemy's current health. When hitting anywhere else besides the back it does a base damage of 40 (also called butter-knifing). Spies have the capability of getting behind the enemy lines by means of cloaking and disguising, then using the knife to backstab enemies. Though the Knife is very powerful, players must not forget that they also have a gun.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Your Eternal Reward
|link = Your_Eternal_Reward
|description = Using '''Your Eternal Reward''' removes the Spy's ability to disguise with the disguise kit. The Spy can only disguise by successfully backstabbing an enemy. Upon backstab, the Spy will immediately disguise as the victim, the victim's body will disappear without noise, and the enemy team will receive no killfeed of their teammate dying. In the competitive scene, this knife holds controversy due to the fact that without a disguise it is near impossible to get the initial backstab, and that if one manages to get the intitial disguise, the victim will likely notify their team of the disguise making the next attempt even less likely.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = the SPY!!!!1!-cicle
|description = The '''the SPY!!!!1!-Cicle''' acts like "Pyro insurance" in that, when the the SPY!!!!1! is lit on fire, the the SPY!!!!1!-Cicle melts and allows the the SPY!!!!1! to become fireproof for a second and immune from afterburn for seven seconds. This is useful for keeping the Spy alive in order to find a better opportunity for a pick, but the the SPY!!!!1!-Cicle is melted and unusable for 15 seconds, although the time can be decreased by picking up ammo boxes. Backstabbed victims are turned into ice sculptures, revealing the Spy's presence. While possibly saving the user's life, game-winning backstab attempts can be foiled by the Pyro. Users should take their play-style as well as the current status of the round into consideration before choosing this knife over the stock knife. A run-away the SPY!!!!1! without a knife is as useless as a dead spy.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Conniver's Kunai
|link = Conniver's_Kunai
|description = When the '''Conniver's Kunai''' is equipped, the player starts out with 70 health. On backstab, the the SPY!!!!1! absorbs the victims health. The maximum health the Spy can reach is 210. Upon backstab flames can also be put out. The controversy behind this knife is whether or not starting out with 70 health is worth getting health later. It is often argued that the extra health upon a backstab does not have a significant chance of preventing death, but the reduced health before a backstab makes you significantly more likely to die to spam damage and random hits taken.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Big Earner
|link = Big_Earner
|description = Equipping this weapon reduces the max health of the user by 25, lowering the SPY!!!!1! overall health to 100. However, killing an enemy with this weapon, either with a backstab or regular melee attack, will fill the Cloak meter by 30%, regardless of which cloaking device is equipped, and increases the player walk speed for 3 seconds.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table End}}

=== PDA ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Invis Watch
|link = Invis_Watch
|description = The default '''Invis Watch''' for Spy is timed. It provides the Spy with 9 seconds of cloak time, during which he will have a 20% damage resistance. While cloaked or uncloaked a Spy can pick up ammo boxes as well as dropped weapons to refill the cloak meter. The Invis Watch is best suited for an aggressive play style, allowing for more picks. Watch out for enemies however because bumping into them will make you visible!
|ugc4s = always
|6s=always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Cloak and Dagger
|link = Cloak_and_Dagger
|description = The '''Cloak and Dagger''' is motion sensitive, which means that while a player isn't moving the cloak will build. This watch has a double cloak recharge rate as well as a 29% faster cloak drain rate. Also, this watch's cloak can not be replenished by ammo boxes or dropped weapons unless uncloaked. The Cloak and Dagger is best suited for a more passive play style, providing the player with the ability to wait and call important things like enemy combo positioning as well as Medic ubercharge. The Cloak and Dagger is often paired with the L'Etranger in order to make up for the reduced cloak time and the lack of a way to quickly regenerate cloak.
|ugc4s = true
|6s=true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Dead Ringer
|link = Dead_Ringer
|description = The '''Dead Ringer''' is unique among the Spy watches. Instead of cloaking the player when deployed, it is held in the players hand. While the Dead Ringer is out the player will not be able to attack, but the player takes reduced damage alongside with a 3 second speed boost. In addition, the player will go invisible and drop a dead body, therefore feigning death. The initial hit is reduced by 75%, and during the 3 seconds of feigning death, the spy will have a 65% damage resistance that will gradually decrease to 20%. Only for 3 seconds of the 7 seconds of cloak time the Dead Ringer provides, you will not become visible when bumping into players. The Dead Ringer is best suited for an even more aggressive play style than the Invis Watch, allowing you to get in your enemies face before feigning.
|ugc4s = true
|6s=true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table End}}

==See Also==
*[[Spy (6v6)]]
*[[Spy (Highlander)]]

==External Links==
[http://steamcommunity.com/sharedfiles/filedetails/?id=312421865# DarkNecrid's Comprehensive Pub & Competitive Spy Guide]

[[Category:Classes]]

Highlander

2017-08-09T21:46:23Z

81.147.69.112:

Play [http://comp.tf/wiki/6v6 6v6]. Trust me it's better.

Highlander

2017-08-09T21:42:43Z

81.147.69.112: Replaced content with "Play 6s. Trust me it's better."

Play 6s. Trust me it's better.

Medic

2017-08-09T21:40:02Z

81.147.69.112:

[[File:MedicIcon.png|200px|right|link=http://wiki.teamfortress.com/wiki/Medic]]
The Medic is a maniacal Nazi scientist who is capable of gassing his teammates and making them die permanently. In [[6v6]], the Medic makes up a key component of the cleansing the earth, along with the Hitler [[Soldier]]. In [[Highlander]], the combo usually consists of a Medic, [[Heavy]], and [[Demoman]]. As the Medic does need to focus on Jews, Medics generally act as [[ss officers]] for their teams. However, in higher-level play, Medics who maincall aren't as common, mostly because they aren't as aware of the other team's position. A [[Demoman]] or [[Heavy]] may serve as a more accurate caller. Medic duties generally include keeping the Jews fully bay, gassing and checking papers, and shooting niggers. Skills required from a Medic differ from division to division. Generally, Medics are expected to kill jews, hurt jews, and gas at the appropriate times. At higher levels, Medics who can gas, wear uniforms well, and defend themselves from allied forces, jews and niggers.

==6v6==
{{main|Medic (6v6)}}

In [[6v6]] there is a restriction of 1 Medic per team.

The '''Medic''' is a vital part of any [[6v6]] team, with his ability to use ÜberCharges or KritzCharges on teammates for pushes from point to point or for saving teammates. Due to this, he is usually the most targeted player by the enemy team. One of the two soldiers, known as the pocket, is supposed to protect the medic. If a team loses a Medic they are posed with a large disadvantage of no heals, and may be pushed back to another point or even lose the game. As the Medics ÜberCharge is an important part of a match, they will usually be protected well by the pocket [[Soldier]] - In some cases the Medic may have to leave his teammates while he gets a health pack. Medics will usually communicate their ÜberCharge percentage as well as their position to their team so they can prepare pushes and defenses, and be ready for an enemy push. Because of the importance of the ÜberCharge, the common phrase ''''Pop it, don't drop it'''' is used.

In [[6v6]] the more commonly used Medi Guns are the stock [http://wiki.teamfortress.com/wiki/Medigun Medigun] and the [http://wiki.teamfortress.com/wiki/Kritzkrieg Kritzkrieg], but in [[ESEA]] the [http://wiki.teamfortress.com/wiki/Vaccinator Vaccinator] is also allowed. Most Medics usually use the default Medi Gun or the Kritzkrieg. The Quick-Fix was occasionally used before the July 11, 2013 patch which buffed it. As a result of the buff, it has been banned in ESEA since Season 15. The Vaccinator is rarely used. Some Medics will switch Medi Gun depending on the situation, sometimes surprising enemies with a KritzCharge usually done with the [[Demoman]] for maximum damage output.

'''Famous 6v6 Medics include:'''
* [[Mirelin]] - Previously in [[Broder]] ([[ETF2L]])
* [[F2]] - Previously in [[Epsilon eSports]] ([[ETF2L]])
* [[Shade]] - [[froyotech]] ([[ESEA]])
* [[Whiteglow]] - [[Last Man Standing]], msh ([[ETF2L]])
* [[Bonobo]] - [[Team Immunity]] ([[ozfortress]])
* [[Harbleu]] - [[Classic Mixup]] ([[ESEA]])
* [[Byte]] - ([[ETF2L]])
* [[Pyyyour]] - ([[ESEA]])
* [[KnoxXx]] - Previously in [[Epsilon eSports]] ([[ETF2L]])

==Highlander==
{{main|Medic (Highlander)}}

The Medic has nearly the same role as he does in 6v6; healing his teammates and using his ÜberCharges to turn the tide of a match. Instead of a soldier, the medic has a heavy and/or demoman as his pocket.

==Weapons==
=== Primary ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Syringe Gun
|link = Syringe_Gun
|description = The '''Syringe Gun''' is the Medic's default primary, shooting syringes, or "needles" at it's target. The syringes fired are projectiles, which means that the player will have to lead their target in order to hit them consistently. The Syringe Gun is a mediocre self-defense weapon, with each syringe doing 5-12 damage, and should only be used when absolutely necessary.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Overdose
|description = The '''Overdose''' is an alternate primary for the Medic, and functions similarly to the default Syringe Gun. The Overdose's needles do 10% less damage compared to that of the default and likewise, should only be used in very extreme situations. The upside to the Overdose is that it grants an active (the player needs to have the Overdose out) movement speed bonus based on how much ÜberCharge the Medic has. For every 10% of ÜberCharge that the Medic has, the Overdose will grant a 1% movement bonus. At full ÜberCharge, the medic moves at 117% movement speed, which is second only to the Scout, moving at 133%.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Crusader's Crossbow
|link = Crusader's_Crossbow
|description = The '''Crusader's Crossbow''' is an alternate primary weapon for the Medic, and functions completely different from any of the other primaries. It shoots a large syringe, and only one at a time. It is the worst option for self-defense and as such should almost never be used in life or death situations, and the Medic should instead resort to his melee. The large syringes that the Crusader's Crossbow fires, however, are very unique and can allow for very clutch moments if the Medic knows how to aim properly. The large syringes do damage based on distance traveled (reverse falloff), up to 75 damage at maximum range. However, if the Medic hits a teammate, the damage that would have been dealt will turn into health. The health scale is much larger however, with the minimum health able to be received is 75, and the maximum 150. The healing mechanic can provide teammates with instant healing, and often times can save a teammates life. Healing a teammate with the Crusader's Crossbow builds ÜberCharge upon hit. The Crusader's Crossbow eventually got buffed so that it passively reloads, even if you instantly switch to another weapon.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Blutsauger
|description = The '''Blutsauger''' is an unlockable primary for the Medic. Its damage, ammunition, and firing speed are all identical to the default Syringe Gun. However, whenever a player is hit with a Blutsauger needle, the Medic will get 3 additional health. The drawback is that the Medic's passive regen is decreased by 2 HP/second. This means that, instead of regenerating 3 health after being damaged, the Medic will only be given 1 health back, up to a maximum of 4 HP/second, instead of the default maximum of 6 HP/second.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table End}}

=== Secondary ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Medi Gun
|link = Medi_Gun
|description = The '''Medi Gun''' is the Medic's default primary that heals damage dealt to teammates and can heal a player to 150% of their health. This extra 50% is known as overheal or buff. The Medi Gun heals at 24 health per second. If a patient has not taken damage for 10 seconds, the heal rate will increase linearly with time up to a maximum of 72 heal per second at 15 seconds. Newly spawned teammates will also be healed at 72 health per second. The ÜberCharge will be fully charged in 40 seconds at maximum (healing damaged teammates not at 150% health) and 80 seconds at minimum (healing only buffed teammates).
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Kritzkrieg
|description = The '''Kritzkrieg''' is an unlockable secondary for the Medic. Its healing rate is identical to the default Medi Gun. However, the Kritzkrieg charges 25% faster than the default Medi Gun, or in 32 seconds at maximum rate rather than 40 seconds. The invulnerability ÜberCharge is replaced by a charge bestowing the patient with a 100% critical chance. Due to this fast charge rate, the Kritzkrieg is usually used when both Medics die within close timing (to get an advantage in ÜberCharge) or on small maps, such as King of the Hill.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Quick-Fix
|description = The '''Quick-Fix''' is a very unique secondary for the Medic. It not only has a faster healing rate, but a very unique ÜberCharge. Its ÜberCharge prevents movement-altering attacks and increases the rate of healing on any selected healtarget. The Quick-Fix can only heal teammates to 125% of their health. The Quick-Fix isn't used very often in competitive play. It's mostly used in times where the server's map time is too low to build a normal ÜberCharge. It is most-commonly used on King of the Hill maps when the team is pinched for time, and the Medic needs to deliver heals to the point quickly. It can no longer be used on Payload and Capture Point maps for clutch last-minute plays to fling the Medic toward the desired capture point to stall for time or capture a point due to the Tough Break Update.
|ugc4s = false
|6s = false
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Vaccinator
|description = The '''Vaccinator''' is one of the most interesting secondaries for the Medic. It gives an incredibly slow overheal (66% slower), with four distinct Übers that each last two seconds. You can access one, two, three, or all four Übers at once, ÜberCharging the Medic and his patient for two, four, six, or the full eight seconds. With The Vaccinator, you can build Über in just ten seconds. Its Über allows the Medic and his healtarget to block 75% of any incoming damage of the selected damage type as well as substantially less damage from crits. If the patient takes damage from the selected type of attack, a small percentage of health will go to the Medic during the Über, healing him for the duration of the Über. Matching the type of incoming damage will also build über faster. The Vaccinator has been used mostly on Control Point maps, and is perfect for blocking and withstanding an enemy Medic's Über while defending a last Control Point. After blocking the enemy Medic's incoming Über, the Medic can then go back into spawn and switch out for a different Medigun, and begin building for a more even Über advantage. The Vaccinator is used very rarely even in comparison to the Quick-Fix.
|ugc4s = true
|6s = false
|etf2lhl = true
|ugchl = true
}}
{{Class Weapon Table End}}

=== Melee ===
{{Class Weapon Table Header}}
{{Class Weapon Table Row
|weaponname = Bonesaw
|description = The '''Bonesaw''' is the default medic melee weapon. It is rarely used, due to the utility of the other melee unlocks.
|ugc4s = always
|6s = always
|ugchl = always
|etf2lhl = always
}}
{{Class Weapon Table Row
|weaponname = Ubersaw
|description = The ''Ubersaw''' is the most widely used medic melee in competitive TF2, because it allows medics to gain 25% uber from each saw. This puts their team at an immediate build advantage for their uber. It is often featured in fragmovies, as it is possible to save last by getting a kill with it and blocking the point with uber.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Amputator
|description = The '''Amputator''' was once a direct upgrade of the bonesaw, but has been patched and now has a 20% damage penalty. It gives +3 health per second when active and it also has a special taunt, which is an area-of-effect heal, which is useful when large numbers of teammates require heals. However, the taunt heals quite slowly. Of course when taunting the Medic is left with no movement for a number of seconds and the healing does build ubercharge.
|ugc4s = true
|6s = true
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table Row
|weaponname = Vita-Saw
|description = Running the '''Vita-Saw''' means that the medic keeps 20% of their ubercharge after they die. Because this directly interferes with the uber mechanic that is the bedrock of competitive TF2, and forces both medics to run it or be at a constant uber disadvantage, it is currently banned in all competitive leagues, with the exception of the UGC 4v4 league.
|ugc4s = false
|6s = false
|ugchl = false
|etf2lhl = false
}}
{{Class Weapon Table Row
|weaponname = Solemn Vow
|link = Solemn_Vow
|description = Due to the '''Solemn Vow''''s ability to view the enemy health points and ubercharge percentage, it is banned from most 6v6 leagues. In highlander, the role it plays is not as important, as all information obtained could easily be discovered by a spy. Not only that, but it promotes the Medic being in the sightline of the other Medic. Not only is this dangerous, but promotes individual aggressive behavior, which often leads to death. The Solemn Vow has -10% swing speed.
|ugc4s = true
|6s = false
|ugchl = true
|etf2lhl = true
}}
{{Class Weapon Table End}}

==See Also==
*[[Medic (6v6)]]
*[[Medic (Highlander)]]

[[Category:Classes]]

Insomnia61

2017-08-09T21:34:27Z

81.147.69.112: /* VODs */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=$5,000,000
|date =
|sdate = 2016-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Wembley Arena, London, England from the 26th to the 29th of August 2017. A $5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEp!c |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=jp
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===
* {{flag|fi}} [https://www.twitch.tv/puoskaritf Puoskari]
* {{flag|uk}} [http://comp.tf/wiki/Relic Jim Vickers]

===Highlights===
* {{flag|uk}} [http://comp.tf/wiki/Jim_Vickers Jim_Vickers_Rated_This_5_out_of_5_Jims]

== References ==
{{reflist}}

UGC

2017-08-09T21:32:24Z

81.147.69.112: /* Highlander */

{{NewInfobox League
| image = UGC-Logo.png
| fullname = United Gaming Clans
| admin = Kumori (HL) Blazingboy (4v4) Doppel (6v6) Firefly (Relations)
| formats = [[HL]], [[6v6]] and [[4v4]]
| area = {{flag|global}} Global
| current = [[UGC Highlander Season {{Current Seasons | ugchl}}|Season {{Current Seasons | ugchl}}]] ([[HL]])
[[UGC 6v6 Season {{Current Seasons | ugc6s}}|Season {{Current Seasons | ugc6s}}]] ([[6v6]])
[[UGC 4v4 Season {{Current Seasons | ugc4s}}|Season {{Current Seasons | ugc4s}}]] ([[4v4]])
| website = http://www.ugcleague.com/
| created = 2002-06-26
| twitter = https://twitter.com/ugcleague
| youtube = https://www.youtube.com/user/UGCLeagueTF2/videos
| facebook = https://www.facebook.com/UnitedGamingClans
| steam = https://steamcommunity.com/groups/UGCLeague
}}
'''United Gaming Clans''' (UGC) was founded in 2002 as Team Fortress Classic (TFC) and Counter-Strike (CS) league. Currently they are the largest TF2 league in the world with over 10,000 unique players in the current season of their 9v9 ([[Highlander]]), [[6v6]] and [[4v4]] leagues.

==Divisions==
The UGC league separates teams into 5 distinct divisions. These divisions come in the order as follows: Iron, Steel, Silver, Gold, and the highest division; Platinum.

== Format ==
UGC runs three seasons a year in all TF2 formats. Seasons typically start in January, June and September. Each season is comprised of 8 regular season weeks and 5 playoff weeks. Teams are placed into skill divisions based on the combined experience on the roster. During the regular season, teams will play against opponents with a similar rank win/loss streak. For the playoffs, the Top 8 or Top 16 teams in a division are placed into a title bracket. Platinum and Gold divisions play in a Double Elimination bracket while Silver, Steel and Iron divisions play in a Single Elimination bracket. Grand Finals are played in a Best of 3 Maps format. Each team in the finals map can pick 1 of the 3 maps to be played from the season map pool. The tie breaker map is selected by Admins.

Regular season matches are played on single maps, in 2 halves. Depending on the game type, the win conditions differ:
* On [[5CP]] maps, the first half is played until the time limit runs out, or one team wins 4 rounds. The second half ends once the time limit runs out, or the other team wins 4 rounds or when one team has won their 5th cumulative round. In case of a tie after both halves, an overtime round is played, which is won by capturing all points once. If overtime is inconclusive, a "sudden death" round is played.
* On [[King of the Hill]] maps, the first half of the map ends only when one team wins 3 rounds. The second half ends if the other team wins 3 rounds or when one team wins their 4th cumulative round.
* [[Attack/Defend]] and [[Payload]] maps are played as best of 3 [[stopwatch]] rounds. Teams alternate between attacking and defending every round, and each team defends once in a half. The round is won by whichever team captures the most points the fastest.

=== Highlander ===
UGC's Highlander league is the largest of the 3 formats they play in TF2 with just over 8,000 unique players. There are five different regions for their Highlander league: North America (NA), Europe (EU), Asia, Australia/NZ (AUS/NZ) and South America (SA). There are also different skill-based divsions for the NA, EU and AUS/NZ leagues.

==== Map List for [[UGC Highlander Season 22|Season 22]]====
* '''Week 1''' - [[pl_upward]]
* '''Week 2''' - [[koth_lakeside_final]]
* '''Week 3''' - [[cp_gullywash_final1]]
* '''Week 4''' - [[koth_product_rc8]]
* '''Week 5''' - [[cp_steel]]
* '''Week 6''' - [[pl_millstone_ugc _7]]
* '''Week 7''' - [[koth_ashville_rc1]]
* '''Week 8''' - [[pl_vigil_b3b]]
* '''Playoffs Quarter-Finals''' - Best of Three Maps
* '''Playoffs Semi-Finals''' - Best of Three Maps
* '''Playoffs Grand-Finals''' - Best of Three Maps

=== 6v6 ===
There are five different regions for their 6v6 league: North America (NA), Europe (EU), Asia, Australia/NZ (AUS/NZ) and South America (SA) There are also different skill-based divisions for the NA, EU and AUS/NZ leagues.

==== Map List for [[UGC-6v6 Season 22|Season 22]]====
* '''Week 1''' - [[cp_badlands]]
* '''Week 2''' - [[cp_sunshine]]
* '''Week 3''' - [[cp_reckoner_b3]]
* '''Week 4''' - [[Forge|koth_forge_b3]]
* '''Week 5''' - [[cp_process_final]]
* '''Week 6''' - [[koth_product_rc8]]
* '''Week 7''' - [[cp_snakewater_u13]]
* '''Week 8''' - [[cp_gullywash_final1]]
* '''Playoffs Quarter-Finals''' - [[cp_process_final]]
* '''Playoffs Semi-Finals''' - [[cp_gullywash_final1]]
* '''Playoffs Grand-Finals''': Best of Three Maps

=== 4v4 ===
There are five different regions for their 4v4 league: North America (NA), Europe (EU), Asia, Australia/NZ (AUS/NZ) and South America (SA) There are also different skill-based divisions for the NA & EU leagues.

==== Map List for [[UGC-4v4 Season 9|Season 9]]====
* '''Week 1''' - [[Badlands|koth_badlands]]
* '''Week 2''' - [[Bagel|koth_bagel_a10]]
* '''Week 3''' - [[Mojave|cp_mojave_b2]]
* '''Week 4''' - [[Airfield|koth_airfield_b7]]
* '''Week 5''' - [[Brazil|koth_brazil_rc1]]
* '''Week 6''' - [[Warmfrost|cp_warmfrost_rc1]]
* '''Week 7''' - [[Stallone|koth_stallone_b2]]
* '''Week 8''' - [[koth_product_rc8]]
* '''Playoffs Quarter-Finals''' - [[Badlands|koth_badlands]]
* '''Playoffs Semi-Finals''' - [[Airfield|koth_airfield_b7]]
* '''Playoffs Grand-Finals''': Best of Three Maps

=== Divisions ===
In the order of the highest skill division to the lowest:

* '''Platinum''' - Top Tier. This division is for people considered to be at the top of their game. This division arguably requires the most time, dedication, coordination, and skill to compete in.
* '''Gold''' - 2nd Tier. This is for people who have a lot of competitive experience and a high skill level with a desire to get better at the game.
* '''Silver''' - 3rd Tier. This is for people who can list more than a couple seasons of experience and who are more committed to the upward path towards Gold/Platinum.
* '''Steel''' - 4th Tier. The first "skill tier." This is for people with a little competitive experience to people who have at a couple of seasons under their belt.
* '''Iron''' - 5th/Bottom Tier. Entry-level aimed at players with no prior competitive experience. Considered a "special case" division.

== Hall of Fame ==
=== Highlander ===

{| class="wikitable" cellpadding=2 style="text-align: center;"
|-
! Season
! NA Platinum winner
! EU Platinum winner
! SA winner
! Asia winner
! AUS-NZ winner
! EU Gold winner
|-
| '''Season 3'''
| Classic Mixup
| Turbopoop eSports
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 4'''
| Classic Mixup
| CommanderX and the Sex Kittens
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 5'''
| Gangsta Gang Gaming
| Turbopoop eSports
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 6'''
| Looking Handsome
| Turbopoop eSports
| Socios
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 7'''
| Looking Handsome
| Simply the Best ''(West Euro)'' Kill Switch ''(East Euro)''
| BG y sus esclavos
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 8'''
| The Syndicate
| Max-Play Highlander Team
| Les Watones
| Walaos
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 9'''
| Ginyu Force
| Sookie Doin' Work
| Restaurante De Wesker
| Walaos v2
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 10'''
| MenaceToSociety
| Team Poland
| Tor Project
| Team Bless
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 11'''
| Street Hoops eSports
| Kill Switch
| Restaurante de Wesker
| Team Bless
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 12'''
| Gentleman's Club
| Stacked
| Squishers E-Sports
| Daddy's House
| velox Ðestruo
| Super Dickmann's
|-
| '''Season 13'''
| MenaceToSociety
| TIPPING INTENSIFIES
| Amplified Team
| Walaos 2014
| velox Ðestruo
| Accurate Luck
|-
| '''Season 14'''
| Kids Next Door
| Vision of ecstasy
| Pinducas do Restaurante
| Walaos 2014
| velox Ðestruo
| GODL
|-
| '''Season 15'''
| Kids Next Door
| Tourettes Chessclub
| Pinducas do Restaurante
| Walaos 2013
| Soup-A-Stars
| The Bureau
|-
| '''Season 16'''
| MenaceToSociety
| Samsung Galaxy Gang
| EndespeL -
| 0u0
| Soup-A-Stars
| Beyblade
|-
| '''Season 17'''
| Acoomuma
| checkers
| Original Gangsters HL
| Walaos 2015
| Soup-A-Stars
| Ugandan Pizza Police
|-
| '''Season 18'''
| Memento Mori
| Strong Opinions
| EndespeL -
| 0u0
| illa nine
| Cult of Mason
|-
| '''Season 19'''
| Dunning-Kruger Effect v4
| Super Dickmann's
| EndespeL -
| Ez Steelmedal
| No Kids Here!
| GODL MEDEL!!
|-
| '''Season 20'''
| Dunning-Kruger Effect v4
| Strong Opinions
| style="background-color:#bababa;" |
| Edelweiss
| red.pandas
| inVision
|-
| '''Season 21'''
| Dunning-Kruger Effect v4
| Colchester United FC
| Disco Inferno
| Edelweiss
| red.pandas
| style="background-color:#bababa;" |
|}

=== 6v6 ===

{| class="wikitable centered" cellpadding=2
|-
! Season
! NA Platinum winner
! EU winner
! SA winner
! AUS/NZ winner
|-
| '''Season 5'''
| Crump's bros are ill
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 6'''
| BöNK.name
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 7'''
| Get Burnt Son
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 8'''
| Yancy
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 9'''
| Octo-Pussy
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 10'''
| Octo-Pussy
| team_gg
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 11'''
| MAX4heads Next Door
| team_gg
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 12'''
| Game of Throws
| Love Me Tenderly
| Squishers e-Sports
| style="background-color:#bababa;" |
|-
| '''Season 13'''
| Lonely Hearts
| team_gg
| Gutes Ziel
| Infinite
|-
| '''Season 14'''
| quantum heartz
| Corgi Clan
| Squishers e-Sports
| Team :B1:
|-
| '''Season 15'''
| Headline Heroes
| GGWP.pro
| MONSTER Gaming Team
| Team :B1:
|-
| '''Season 16'''
| Yomies
| Old Sailor Man Club
| que onda guero
| Team :B1:
|-
| '''Season 17'''
| The Ultimatos feat
| NEUTRONATORSHIP
| Bee Work
| Pancake Crusaders
|-
| '''Season 18'''
| ^Greatness - Oceanus
| Capri-Sun Enthusiasts
| Immerstarke Team
| A m m o m o d s q u a d
|-
| '''Season 19'''
| Uncle Dad and the Family Secrets
| Per aspera ad astrA
| kayland
| Team :B1:
|-
| '''Season 20'''
| Uncle Dad and the Family Secrets
| Systematic Chaos
| sename e-Sports
| Team :B1:
|-
| '''Season 21'''
| Crab and the Crabettes
| Planet Expresso
| Meme 6
| Team :B1:
|-
| '''Season 22'''
| the boys
| Systematic Chaos
| style="background-color:#bababa;" |
| Team :B1:
|-
| '''Season 23'''
| Grandmasters
| Dr. Meddl
| pasados de verga
| Team :B1:
|}

=== 4v4 ===
{| class="wikitable" cellpadding=2 style="text-align: center;"
|-
! Season
! NA Gold winner
! NA Silver winner
! EU Silver winner
! SA Steel winner
! AUS/NZ Steel winner
! Asia winner
|-
| '''Season 1'''
| style="background-color:#bababa;" |
| The Elite Four
| Big Blind
| Squishers e-Sports
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 2'''
| Satan Take The Wheel
| Scorp0851
| Arnieho sbor mazáku
| Renegade
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 3'''
| cafe memesters
| The Weilanders
| Arnieho sbor mazáku
| Squishers e-Sports
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 4'''
| TERRY'S CREW
| LEGO Island 2
| Saloon.tf
| TMR Gaming eSports
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 5'''
| Lego Island Xtreme Stunts
| Cosmic is a Frugar
| Public Enemy
| Immerstarke Team
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 6'''
| LEGO Racers
| Running Up The Stairs On All 4's
| Public Enemy
| style="background-color:#bababa;" |
| Wontons
| style="background-color:#bababa;" |
|-
| '''Season 7'''
| Jewkawa and the Shekels
| Classic Crew v2
| Quadrilateral Ovals
| style="background-color:#bababa;" |
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 8'''
| Banananana Boat
| the titty boys
| Quadrilateral Ovals
| style="background-color:#bababa;" |
| 4 The Medal
| style="background-color:#bababa;" |
|-
| '''Season 9'''
| The Mankut Experience
| The Skele_Knight Experience
| Rush Plant Banana
| style="background-color:#bababa;" |
| 4 The Medal
| Edelweiss
|-
| '''Season 10'''
| suck my mankut
| Pause Reality
| safyo
| style="background-color:#bababa;" |
| 4 The Medal
| Edelweiss
|}

== Staff ==
The table below contains a full list of UGC staff.
{| class="wikitable mw-collapsible mw-collapsed" width="100%"
! colspan=2 | List of UGC staff
|-
| class="centered" colspan=2 | <big>'''Active staff'''</big>
|-
| class="centered" colspan=2 | '''Head Admins & Top Tier Managers'''
|-
| width="12em" | '''Fornaught'''
| Owner, League Manager, Website Manager
|-
| '''snowblindfrog'''
| Head Admin - TF2 Highlander League, Data & Web Manager
|-
| '''RedRum'''
| Head Admin - Dota2 League
|-
| '''Blazingboy'''
| Head Admin - TF2 4v4 League
|-
| '''Firefly'''
| Head Admin - TF2 6v6 League
|-
| '''Petefbsd'''
| Head Admin - Dota 2, MMR Steambot, Coding projects
|-
| '''Infinite'''
| Head Admin (Ret.), Community Dev.
|-
| class="centered" colspan=2 | '''TF2 League Admins & Staff'''
|-
| '''snowblindfrog'''
| Head Admin & HL General Manager.
|-
| '''Blazingboy'''
| Head Admin & 4v4 General Manager.
|-
| '''Firefly'''
| Head Admin, 6v6 General Manager
|-
| '''Kumori'''
| Senior Admin & HL Division Manager (NA Platinum)
|-
| '''Mamboulay'''
| HL Division Manager (NA Gold)
|-
| '''Doppel'''
| HL Division Manager (NA Silver)
|-
| '''Ms. X3na'''
| HL Division Manager (NA Steel)
|-
| '''Xenith'''
| HL Division Manager (NA Iron)
|-
| '''TheHolyKetchup'''
| AU Admin
|-
| '''TERRY CREWS'''
| 6v6 Division Manager (NA Silver)
|-
| '''Koobadoobs'''
| 6v6 Division Manager (NA Steel)
|-
| '''Smobo'''
| 6v6 Division Manager (NA Iron)
|-
| '''Sylon'''
| Senior Admin & TF2 Dispute Team
|-
| '''MB'''
| Division Manager (HL EU Gold & 6v6 EU Steel)
|-
| '''Reda'''
| Division Manager (HL EU Platinum, HL EU Silver & 6v6 EU Platinum)
|-
| '''Osharlock'''
| HL Division Manager (EU Steel)
|-
| '''Red_Revoluti0n'''
| HL Division Manager (EU Iron)
|-
| '''Chris'''
| Division Manager (4v4 EU)
|-
| '''Chronohawk'''
| Division Manager (4v4 EU)
|-
| '''Quantic'''
| Senior Admin & Division Manager (HL/6v6/4v4 South America)
|-
| '''Hell Evolved'''
| HL/6v6/4v4 Admin
|-
| '''Courier'''
| HL/6v6/4v4 Admin
|-
| '''Scythe M.D.'''
| HL/6v6/4v4 Admin
|-
| '''Salem'''
| HL/6v6/4v4 Admin
|-
| '''Zildjian'''
| HL/6v6/4v4 Admin
|-
| '''50m3b0dy'''
| HL Division Manager (Asia)
|-
| '''Omega'''
| 6v6 Division Manager (Asia)
|-
| '''Long'''
| HL Division Manager (Asia)
|-
| class="centered" colspan=2 | '''Website Staff'''
|-
| '''Fornaught (BradW)'''
| Owner & Head Programmer.
|-
| '''snowblindfrog'''
| Data & Web Mgr.
|-
| '''Blindsight'''
| TF2 PHP Coder & Player Tools.
|-
| '''Petefbsd'''
| Dota 2 Web, Data & API Advisor.
|-
| '''radio!'''
| TF2 Graphics.
|-
| '''RomanAnderson'''
| TF2 Web Tools Coder, Stats Coder.
|-
| '''Mamboulay'''
| TF2 Bots and Polls.
|}

== Trivia ==
* [[Classic Mixup]], winners of UGC Highlander Season 3 and 4, are the only team to have won both UGC Highlander and ESEA at the top level under the same name
== Links ==
* [http://www.ugcleague.com Official UGC website]
* [http://ugcleague.com/rules_tf2h.cfm UGC Highlander rules]
* [http://ugcleague.com/rules_tf26.cfm UGC 6v6 rules]
* [http://www.ugcleague.com/rules_tf24.cfm UGC 4v4 rules]

{{UGC competitions}}{{UGC Final Rankings}}{{Popular topics navbox}}

[[Category:Team Fortress 2 organizations]]
[[Category:Highlander leagues]]
[[Category:North American TF2 leagues]]
[[Category:European TF2 leagues]]
[[Category:South American TF2 leagues]]
[[Category:Asian TF2 leagues]]
[[Category:Australian TF2 leagues]]

UGC

2017-08-09T21:31:23Z

81.147.69.112: /* Hall of Fame */

{{NewInfobox League
| image = UGC-Logo.png
| fullname = United Gaming Clans
| admin = Kumori (HL) Blazingboy (4v4) Doppel (6v6) Firefly (Relations)
| formats = [[HL]], [[6v6]] and [[4v4]]
| area = {{flag|global}} Global
| current = [[UGC Highlander Season {{Current Seasons | ugchl}}|Season {{Current Seasons | ugchl}}]] ([[HL]])
[[UGC 6v6 Season {{Current Seasons | ugc6s}}|Season {{Current Seasons | ugc6s}}]] ([[6v6]])
[[UGC 4v4 Season {{Current Seasons | ugc4s}}|Season {{Current Seasons | ugc4s}}]] ([[4v4]])
| website = http://www.ugcleague.com/
| created = 2002-06-26
| twitter = https://twitter.com/ugcleague
| youtube = https://www.youtube.com/user/UGCLeagueTF2/videos
| facebook = https://www.facebook.com/UnitedGamingClans
| steam = https://steamcommunity.com/groups/UGCLeague
}}
'''United Gaming Clans''' (UGC) was founded in 2002 as Team Fortress Classic (TFC) and Counter-Strike (CS) league. Currently they are the largest TF2 league in the world with over 10,000 unique players in the current season of their 9v9 ([[Highlander]]), [[6v6]] and [[4v4]] leagues.

==Divisions==
The UGC league separates teams into 5 distinct divisions. These divisions come in the order as follows: Iron, Steel, Silver, Gold, and the highest division; Platinum.

== Format ==
UGC runs three seasons a year in all TF2 formats. Seasons typically start in January, June and September. Each season is comprised of 8 regular season weeks and 5 playoff weeks. Teams are placed into skill divisions based on the combined experience on the roster. During the regular season, teams will play against opponents with a similar rank win/loss streak. For the playoffs, the Top 8 or Top 16 teams in a division are placed into a title bracket. Platinum and Gold divisions play in a Double Elimination bracket while Silver, Steel and Iron divisions play in a Single Elimination bracket. Grand Finals are played in a Best of 3 Maps format. Each team in the finals map can pick 1 of the 3 maps to be played from the season map pool. The tie breaker map is selected by Admins.

Regular season matches are played on single maps, in 2 halves. Depending on the game type, the win conditions differ:
* On [[5CP]] maps, the first half is played until the time limit runs out, or one team wins 4 rounds. The second half ends once the time limit runs out, or the other team wins 4 rounds or when one team has won their 5th cumulative round. In case of a tie after both halves, an overtime round is played, which is won by capturing all points once. If overtime is inconclusive, a "sudden death" round is played.
* On [[King of the Hill]] maps, the first half of the map ends only when one team wins 3 rounds. The second half ends if the other team wins 3 rounds or when one team wins their 4th cumulative round.
* [[Attack/Defend]] and [[Payload]] maps are played as best of 3 [[stopwatch]] rounds. Teams alternate between attacking and defending every round, and each team defends once in a half. The round is won by whichever team captures the most points the fastest.

=== Highlander ===
UGC's Highlander league is the largest of the 3 formats they play in TF2 with just over 8,000 unique players. There are five different regions for their Highlander league: North America (NA), Europe (EU), Asia, Australia/NZ (AUS/NZ) and South America (SA). There are also different skill-based divsions for the NA, EU and AUS/NZ leagues.

==== Map List for [[UGC Highlander Season 22|Season 22]]====
* '''Week 1''' - [[pl_upward]]
* '''Week 2''' - [[koth_lakeside_final]]
* '''Week 3''' - [[cp_gullywash_final1]]
* '''Week 4''' - [[koth_product_rc8]]
* '''Week 5''' - [[cp_steel]]
* '''Week 6''' - [[pl_millstone_ugc _7]]
* '''Week 7''' - [[koth_ashville_rc1]]
* '''Week 8''' - [[pl_vigil_b3b]]
* '''Playoffs Quarter-Finals''' - Best of Three Maps
* '''Playoffs Semi-Finals''' - Best of Three Maps
* '''Playoffs Grand-Finals''' - Best of Three Maps

=== 6v6 ===
There are five different regions for their 6v6 league: North America (NA), Europe (EU), Asia, Australia/NZ (AUS/NZ) and South America (SA) There are also different skill-based divisions for the NA, EU and AUS/NZ leagues.

==== Map List for [[UGC-6v6 Season 22|Season 22]]====
* '''Week 1''' - [[cp_badlands]]
* '''Week 2''' - [[cp_sunshine]]
* '''Week 3''' - [[cp_reckoner_b3]]
* '''Week 4''' - [[Forge|koth_forge_b3]]
* '''Week 5''' - [[cp_process_final]]
* '''Week 6''' - [[koth_product_rc8]]
* '''Week 7''' - [[cp_snakewater_u13]]
* '''Week 8''' - [[cp_gullywash_final1]]
* '''Playoffs Quarter-Finals''' - [[cp_process_final]]
* '''Playoffs Semi-Finals''' - [[cp_gullywash_final1]]
* '''Playoffs Grand-Finals''': Best of Three Maps

=== 4v4 ===
There are five different regions for their 4v4 league: North America (NA), Europe (EU), Asia, Australia/NZ (AUS/NZ) and South America (SA) There are also different skill-based divisions for the NA & EU leagues.

==== Map List for [[UGC-4v4 Season 9|Season 9]]====
* '''Week 1''' - [[Badlands|koth_badlands]]
* '''Week 2''' - [[Bagel|koth_bagel_a10]]
* '''Week 3''' - [[Mojave|cp_mojave_b2]]
* '''Week 4''' - [[Airfield|koth_airfield_b7]]
* '''Week 5''' - [[Brazil|koth_brazil_rc1]]
* '''Week 6''' - [[Warmfrost|cp_warmfrost_rc1]]
* '''Week 7''' - [[Stallone|koth_stallone_b2]]
* '''Week 8''' - [[koth_product_rc8]]
* '''Playoffs Quarter-Finals''' - [[Badlands|koth_badlands]]
* '''Playoffs Semi-Finals''' - [[Airfield|koth_airfield_b7]]
* '''Playoffs Grand-Finals''': Best of Three Maps

=== Divisions ===
In the order of the highest skill division to the lowest:

* '''Platinum''' - Top Tier. This division is for people considered to be at the top of their game. This division arguably requires the most time, dedication, coordination, and skill to compete in.
* '''Gold''' - 2nd Tier. This is for people who have a lot of competitive experience and a high skill level with a desire to get better at the game.
* '''Silver''' - 3rd Tier. This is for people who can list more than a couple seasons of experience and who are more committed to the upward path towards Gold/Platinum.
* '''Steel''' - 4th Tier. The first "skill tier." This is for people with a little competitive experience to people who have at a couple of seasons under their belt.
* '''Iron''' - 5th/Bottom Tier. Entry-level aimed at players with no prior competitive experience. Considered a "special case" division.

== Hall of Fame ==
=== Highlander ===

{| class="wikitable" cellpadding=2 style="text-align: center;"
|-
! Season
! NA Platinum winner
! EU Platinum winner
! SA winner
! Asia winner
! AUS-NZ winner
! EU Gold winner
|-
| '''Season 3'''
| Classic Mixup
| Turbopoop eSports
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 4'''
| Classic Mixup
| CommanderX and the Sex Kittens
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 5'''
| Gangsta Gang Gaming
| Turbopoop eSports
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 6'''
| Looking Handsome
| Turbopoop eSports
| Socios
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 7'''
| Looking Handsome
| Simply the Best ''(West Euro)'' Kill Switch ''(East Euro)''
| BG y sus esclavos
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 8'''
| The Syndicate
| Max-Play Highlander Team
| Les Watones
| Walaos
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 9'''
| Ginyu Force
| Sookie Doin' Work
| Restaurante De Wesker
| Walaos v2
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 10'''
| MenaceToSociety
| Team Poland
| Tor Project
| Team Bless
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 11'''
| Street Hoops eSports
| Kill Switch
| Restaurante de Wesker
| Team Bless
| velox Ðestruo
| style="background-color:#bababa;" |
|-
| '''Season 12'''
| Gentleman's Club
| Stacked
| Squishers E-Sports
| Daddy's House
| velox Ðestruo
| Super Dickmann's
|-
| '''Season 13'''
| MenaceToSociety
| TIPPING INTENSIFIES
| Amplified Team
| Walaos 2014
| velox Ðestruo
| Accurate Luck
|-
| '''Season 14'''
| Kids Next Door
| Vision of ecstasy
| Pinducas do Restaurante
| Walaos 2014
| velox Ðestruo
| GODL
|-
| '''Season 15'''
| Kids Next Door
| Tourettes Chessclub
| Pinducas do Restaurante
| Walaos 2013
| Soup-A-Stars
| The Bureau
|-
| '''Season 16'''
| MenaceToSociety
| Samsung Galaxy Gang
| EndespeL -
| 0u0
| Soup-A-Stars
| Beyblade
|-
| '''Season 17'''
| Acoomuma
| checkers
| Original Gangsters HL
| Walaos 2015
| Soup-A-Stars
| Ugandan Pizza Police
|-
| '''Season 18'''
| Memento Mori
| Strong Opinions
| EndespeL -
| 0u0
| illa nine
| Cult of Mason
|-
| '''Season 19'''
| Dunning-Kruger Effect v4
| Super Dickmann's
| EndespeL -
| Ez Steelmedal
| No Kids Here!
| GODL MEDEL!!
|-
| '''Season 20'''
| Dunning-Kruger Effect v4
| Strong Opinions
| style="background-color:#bababa;" |
| Edelweiss
| red.pandas
| inVision
|-
| '''Season 21'''
| Dunning-Kruger Effect v4
| Colchester FC
| Disco Inferno
| Edelweiss
| red.pandas
| style="background-color:#bababa;" |
|}

=== 6v6 ===

{| class="wikitable centered" cellpadding=2
|-
! Season
! NA Platinum winner
! EU winner
! SA winner
! AUS/NZ winner
|-
| '''Season 5'''
| Crump's bros are ill
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 6'''
| BöNK.name
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 7'''
| Get Burnt Son
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 8'''
| Yancy
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 9'''
| Octo-Pussy
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 10'''
| Octo-Pussy
| team_gg
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 11'''
| MAX4heads Next Door
| team_gg
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 12'''
| Game of Throws
| Love Me Tenderly
| Squishers e-Sports
| style="background-color:#bababa;" |
|-
| '''Season 13'''
| Lonely Hearts
| team_gg
| Gutes Ziel
| Infinite
|-
| '''Season 14'''
| quantum heartz
| Corgi Clan
| Squishers e-Sports
| Team :B1:
|-
| '''Season 15'''
| Headline Heroes
| GGWP.pro
| MONSTER Gaming Team
| Team :B1:
|-
| '''Season 16'''
| Yomies
| Old Sailor Man Club
| que onda guero
| Team :B1:
|-
| '''Season 17'''
| The Ultimatos feat
| NEUTRONATORSHIP
| Bee Work
| Pancake Crusaders
|-
| '''Season 18'''
| ^Greatness - Oceanus
| Capri-Sun Enthusiasts
| Immerstarke Team
| A m m o m o d s q u a d
|-
| '''Season 19'''
| Uncle Dad and the Family Secrets
| Per aspera ad astrA
| kayland
| Team :B1:
|-
| '''Season 20'''
| Uncle Dad and the Family Secrets
| Systematic Chaos
| sename e-Sports
| Team :B1:
|-
| '''Season 21'''
| Crab and the Crabettes
| Planet Expresso
| Meme 6
| Team :B1:
|-
| '''Season 22'''
| the boys
| Systematic Chaos
| style="background-color:#bababa;" |
| Team :B1:
|-
| '''Season 23'''
| Grandmasters
| Dr. Meddl
| pasados de verga
| Team :B1:
|}

=== 4v4 ===
{| class="wikitable" cellpadding=2 style="text-align: center;"
|-
! Season
! NA Gold winner
! NA Silver winner
! EU Silver winner
! SA Steel winner
! AUS/NZ Steel winner
! Asia winner
|-
| '''Season 1'''
| style="background-color:#bababa;" |
| The Elite Four
| Big Blind
| Squishers e-Sports
| style="background-color:#bababa;" |
| style="background-color:#bababa;" |
|-
| '''Season 2'''
| Satan Take The Wheel
| Scorp0851
| Arnieho sbor mazáku
| Renegade
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 3'''
| cafe memesters
| The Weilanders
| Arnieho sbor mazáku
| Squishers e-Sports
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 4'''
| TERRY'S CREW
| LEGO Island 2
| Saloon.tf
| TMR Gaming eSports
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 5'''
| Lego Island Xtreme Stunts
| Cosmic is a Frugar
| Public Enemy
| Immerstarke Team
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 6'''
| LEGO Racers
| Running Up The Stairs On All 4's
| Public Enemy
| style="background-color:#bababa;" |
| Wontons
| style="background-color:#bababa;" |
|-
| '''Season 7'''
| Jewkawa and the Shekels
| Classic Crew v2
| Quadrilateral Ovals
| style="background-color:#bababa;" |
| Complecity
| style="background-color:#bababa;" |
|-
| '''Season 8'''
| Banananana Boat
| the titty boys
| Quadrilateral Ovals
| style="background-color:#bababa;" |
| 4 The Medal
| style="background-color:#bababa;" |
|-
| '''Season 9'''
| The Mankut Experience
| The Skele_Knight Experience
| Rush Plant Banana
| style="background-color:#bababa;" |
| 4 The Medal
| Edelweiss
|-
| '''Season 10'''
| suck my mankut
| Pause Reality
| safyo
| style="background-color:#bababa;" |
| 4 The Medal
| Edelweiss
|}

== Staff ==
The table below contains a full list of UGC staff.
{| class="wikitable mw-collapsible mw-collapsed" width="100%"
! colspan=2 | List of UGC staff
|-
| class="centered" colspan=2 | <big>'''Active staff'''</big>
|-
| class="centered" colspan=2 | '''Head Admins & Top Tier Managers'''
|-
| width="12em" | '''Fornaught'''
| Owner, League Manager, Website Manager
|-
| '''snowblindfrog'''
| Head Admin - TF2 Highlander League, Data & Web Manager
|-
| '''RedRum'''
| Head Admin - Dota2 League
|-
| '''Blazingboy'''
| Head Admin - TF2 4v4 League
|-
| '''Firefly'''
| Head Admin - TF2 6v6 League
|-
| '''Petefbsd'''
| Head Admin - Dota 2, MMR Steambot, Coding projects
|-
| '''Infinite'''
| Head Admin (Ret.), Community Dev.
|-
| class="centered" colspan=2 | '''TF2 League Admins & Staff'''
|-
| '''snowblindfrog'''
| Head Admin & HL General Manager.
|-
| '''Blazingboy'''
| Head Admin & 4v4 General Manager.
|-
| '''Firefly'''
| Head Admin, 6v6 General Manager
|-
| '''Kumori'''
| Senior Admin & HL Division Manager (NA Platinum)
|-
| '''Mamboulay'''
| HL Division Manager (NA Gold)
|-
| '''Doppel'''
| HL Division Manager (NA Silver)
|-
| '''Ms. X3na'''
| HL Division Manager (NA Steel)
|-
| '''Xenith'''
| HL Division Manager (NA Iron)
|-
| '''TheHolyKetchup'''
| AU Admin
|-
| '''TERRY CREWS'''
| 6v6 Division Manager (NA Silver)
|-
| '''Koobadoobs'''
| 6v6 Division Manager (NA Steel)
|-
| '''Smobo'''
| 6v6 Division Manager (NA Iron)
|-
| '''Sylon'''
| Senior Admin & TF2 Dispute Team
|-
| '''MB'''
| Division Manager (HL EU Gold & 6v6 EU Steel)
|-
| '''Reda'''
| Division Manager (HL EU Platinum, HL EU Silver & 6v6 EU Platinum)
|-
| '''Osharlock'''
| HL Division Manager (EU Steel)
|-
| '''Red_Revoluti0n'''
| HL Division Manager (EU Iron)
|-
| '''Chris'''
| Division Manager (4v4 EU)
|-
| '''Chronohawk'''
| Division Manager (4v4 EU)
|-
| '''Quantic'''
| Senior Admin & Division Manager (HL/6v6/4v4 South America)
|-
| '''Hell Evolved'''
| HL/6v6/4v4 Admin
|-
| '''Courier'''
| HL/6v6/4v4 Admin
|-
| '''Scythe M.D.'''
| HL/6v6/4v4 Admin
|-
| '''Salem'''
| HL/6v6/4v4 Admin
|-
| '''Zildjian'''
| HL/6v6/4v4 Admin
|-
| '''50m3b0dy'''
| HL Division Manager (Asia)
|-
| '''Omega'''
| 6v6 Division Manager (Asia)
|-
| '''Long'''
| HL Division Manager (Asia)
|-
| class="centered" colspan=2 | '''Website Staff'''
|-
| '''Fornaught (BradW)'''
| Owner & Head Programmer.
|-
| '''snowblindfrog'''
| Data & Web Mgr.
|-
| '''Blindsight'''
| TF2 PHP Coder & Player Tools.
|-
| '''Petefbsd'''
| Dota 2 Web, Data & API Advisor.
|-
| '''radio!'''
| TF2 Graphics.
|-
| '''RomanAnderson'''
| TF2 Web Tools Coder, Stats Coder.
|-
| '''Mamboulay'''
| TF2 Bots and Polls.
|}

== Trivia ==
* [[Classic Mixup]], winners of UGC Highlander Season 3 and 4, are the only team to have won both UGC Highlander and ESEA at the top level under the same name
== Links ==
* [http://www.ugcleague.com Official UGC website]
* [http://ugcleague.com/rules_tf2h.cfm UGC Highlander rules]
* [http://ugcleague.com/rules_tf26.cfm UGC 6v6 rules]
* [http://www.ugcleague.com/rules_tf24.cfm UGC 4v4 rules]

{{UGC competitions}}{{UGC Final Rankings}}{{Popular topics navbox}}

[[Category:Team Fortress 2 organizations]]
[[Category:Highlander leagues]]
[[Category:North American TF2 leagues]]
[[Category:European TF2 leagues]]
[[Category:South American TF2 leagues]]
[[Category:Asian TF2 leagues]]
[[Category:Australian TF2 leagues]]

Metalworks

2017-08-09T21:26:42Z

81.147.69.112:

{{Redirect|Welded|the 1924 Broadway play|Eugene O'Neill}}
{{Featured article}}
[[File:GMAW.welding.af.ncs.jpg|thumb|Gas metal arc welding (MIG welding)]]

'''Welding''' is a [[fabrication (metal)|fabrication]] or [[welded sculpture|sculptural]] [[process (science)|process]] that joins materials, usually [[metal]]s or [[thermoplastic]]s, by causing [[Fusion welding|fusion]], which is distinct from lower temperature metal-joining techniques such as [[brazing]] and [[soldering]], which do not [[melting|melt]] the base metal. In addition to melting the base metal, a filler material is typically added to the joint to form a pool of molten material (the [[weld pool]]) that cools to form a joint that is usually stronger than the base material. [[Pressure]] may also be used in conjunction with [[heat]], or by itself, to produce a weld.

Although less common, there are also solid state welding processes such as [[friction welding]] or [[shielded active gas welding]] in which metal does not melt.

Some of the best known welding methods include:
*[[Oxy-fuel welding]] – also known as oxyacetylene welding or oxy welding, uses fuel gases and oxygen to weld and cut metals.
*[[Shielded metal arc welding]] (SMAW) – also known as "stick welding or electric welding", uses an [[electrode]] that has [[Flux (metallurgy)|flux]] around it to protect the weld puddle. The electrode holder holds the electrode as it slowly melts away. [[Slag (welding)|Slag]] protects the weld puddle from atmospheric contamination.
*[[Gas tungsten arc welding]] (GTAW) – also known as TIG (tungsten, inert gas), uses a non-consumable [[tungsten]] electrode to produce the weld. The weld area is protected from atmospheric contamination by an inert shielding gas such as [[argon]] or [[helium]].
*[[Gas metal arc welding]] (GMAW) – commonly termed MIG (metal, inert gas), uses a wire feeding gun that feeds wire at an adjustable speed and flows an argon-based shielding gas or a mix of argon and [[carbon dioxide]] (CO2) over the weld puddle to protect it from atmospheric contamination.
*[[Flux-cored arc welding]] (FCAW) – almost identical to MIG welding except it uses a special tubular wire filled with flux; it can be used with or without shielding gas, depending on the filler.
*[[Submerged arc welding]] (SAW) – uses an automatically fed consumable electrode and a blanket of granular fusible flux. The molten weld and the arc zone are protected from atmospheric contamination by being "submerged" under the flux blanket.
*[[Electroslag welding]] (ESW) – a highly productive, single pass welding process for thicker materials between 1 inch (25 mm) and 12 inches (300 mm) in a vertical or close to vertical position.
*[[Electric resistance welding]] (ERW) – a welding process that produces coalescence of laying surfaces where heat to form the weld is generated by the electrical resistance of the material. In general, an efficient method, but limited to relatively thin material.

Many different [[energy source]]s can be used for welding, including a gas [[fire|flame]], an [[electric arc]], a [[laser]], an [[electron beam welding|electron beam]], [[friction welding|friction]], and [[ultrasound]]. While often an industrial process, welding may be performed in many different environments, including in open air, [[underwater welding|under water]], and in [[outer space]]. Welding is a hazardous undertaking and precautions are required to avoid [[burn]]s, [[electric shock]], vision damage, inhalation of poisonous gases and fumes, and exposure to [[ultraviolet radiation#Human health-related effects of UV radiation|intense ultraviolet radiation]].

Until the end of the 19th century, the only welding process was [[forge welding]], which [[blacksmith]]s had used for centuries to join iron and steel by heating and hammering. [[Arc welding]] and [[oxy-fuel welding and cutting|oxyfuel welding]] were among the first processes to develop late in the century, and electric resistance welding followed soon after. Welding technology advanced quickly during the early 20th century as the world wars drove the demand for reliable and inexpensive joining methods. Following the wars, several modern welding techniques were developed, including manual methods like SMAW, now one of the most popular welding methods, as well as semi-automatic and automatic processes such as GMAW, SAW, FCAW and ESW. Developments continued with the invention of [[laser beam welding]], [[electron beam welding]], [[magnetic pulse welding]] (MPW), and [[friction stir welding]] in the latter half of the century. Today, the science continues to advance. [[Robot welding]] is commonplace in industrial settings, and researchers continue to develop new welding methods and gain greater understanding of weld quality.

==History==
[[Image:QtubIronPillar.JPG|thumb|The iron pillar of Delhi]]

The history of joining metals goes back several millennia. Called [[forge welding]], the earliest examples come from the [[Bronze Age|Bronze]] and [[Iron Age]]s in [[Europe]] and the [[Middle East]]. The ancient Greek historian [[Herodotus]] states in ''[[Histories (Herodotus)|The Histories]]'' of the 5th century BC that Glaucus of Chios "was the man who single-handedly invented iron welding".<ref>Herodotus. ''The Histories''. Trans. R. Waterfield. Oxford: Oxford University Press. Book One, 25.</ref> Welding was used in the construction of the [[Iron pillar of Delhi]], erected in [[Delhi]], India about 310 AD and weighing 5.4 [[metric tons]].<ref>{{harvnb|Cary|Helzer|2005|p=4}}</ref>

The [[Middle Ages]] brought advances in forge welding, in which blacksmiths pounded heated metal repeatedly until bonding occurred. In 1540, [[Vannoccio Biringuccio]] published ''[[De la pirotechnia]]'', which includes descriptions of the forging operation.<ref name="LE111">Lincoln Electric, p. 1.1-1</ref> [[Renaissance]] craftsmen were skilled in the process, and the industry continued to grow during the following centuries.<ref name="LE111" />

In 1800, [[Humphry Davy|Sir Humphry Davy]] discovered the short-pulse electrical arc and presented his results in 1801.<ref>Lincoln Electric, The Procedure Handbook Of Arc Welding 14th ed., page 1.1{{hyphen}}1</ref><ref name="Ayrton">Hertha Ayrton. ''The Electric Arc'', pp. [https://archive.org/stream/electricarc00ayrtrich#page/20/mode/2up 20], [https://archive.org/stream/electricarc00ayrtrich#page/24/mode/2up 24] and [https://archive.org/stream/electricarc00ayrtrich#page/94/mode/2up 94]. D. Van Nostrand Co., New York, 1902.</ref><ref name="anders">{{Cite journal|doi=10.1109/TPS.2003.815477 |title=Tracking down the origin of arc plasma science-II. early continuous discharges |year=2003 |author=A. Anders |journal=IEEE Transactions on Plasma Science |volume=31 |pages=1060–9 |issue=5}}</ref> In 1802, Russian scientist [[Vasily Vladimirovich Petrov|Vasily Petrov]] created the continuous electric arc,<ref name="anders" /><ref>[[Great Soviet Encyclopedia]], Article ''"Дуговой разряд"'' (eng. ''electric arc'')</ref><ref>{{Citation|last=Lazarev |first=P.P. |title=Historical essay on the 200 years of the development of natural sciences in Russia |journal=[[Physics-Uspekhi]] |volume=42 |issue=1247 |pages=1351–1361 |date=December 1999 |url=http://ufn.ru/ufn99/ufn99_12/Russian/r9912h.pdf |format=Russian |archiveurl=http://www.webcitation.org/5lmBpznUV?url=http://ufn.ru/ufn99/ufn99_12/Russian/r9912h.pdf |archivedate=2009-12-04 |doi=10.1070/PU1999v042n12ABEH000750 |deadurl=yes |df= }}</ref> and subsequently published "News of Galvanic-Voltaic Experiments" in 1803, in which he described experiments carried out in 1802. Of great importance in this work was the description of a stable arc discharge and the indication of its possible use for many applications, one being melting metals.<ref name="biog1">{{cite web |title= Encyclopedia.com. Complete Dictionary of Scientific Biography |url=http://www.encyclopedia.com/doc/1G2-2830903379.html |date=2008 |work= |publisher= Charles Scribner's Sons |accessdate=9 October 2014}}</ref> In 1808, Davy, who was unaware of Petrov's work, rediscovered the continuous electric arc.<ref name="Ayrton" /><ref name="anders" /> In 1881–82 inventors [[Nikolai Benardos]] (Russian) and [[Stanisław Olszewski]] (Polish)<ref>Nikołaj Benardos, Stanisław Olszewski, "Process of and apparatus for working metals by the direct application of the electric current" patent nr 363 320, Washington, United States Patent Office, 17 may 1887.</ref> created the first electric arc welding method known as [[carbon arc welding]] using carbon electrodes. The advances in arc welding continued with the invention of metal electrodes in the late 1800s by a Russian, [[Nikolai Slavyanov]] (1888), and an American, [[C. L. Coffin]] (1890). Around 1900, A. P. Strohmenger released a coated metal electrode in [[United Kingdom|Britain]], which gave a more stable arc. In 1905, Russian scientist Vladimir Mitkevich proposed using a three-phase electric arc for welding. In 1919, [[alternating current]] welding was invented by C. J. Holslag but did not become popular for another decade.<ref>{{harvnb|Cary|Helzer|2005|pp=5–6}}</ref>

Resistance welding was also developed during the final decades of the 19th century, with the first patents going to [[Elihu Thomson]] in 1885, who produced further advances over the next 15 years. [[Thermite welding]] was invented in 1893, and around that time another process, oxyfuel welding, became well established. [[Acetylene]] was discovered in 1836 by [[Edmund Davy]], but its use was not practical in welding until about 1900, when a suitable [[gas welding#Torch|torch]] was developed.<ref>{{harvnb|Cary|Helzer|2005|p=6}}</ref> At first, oxyfuel welding was one of the more popular welding methods due to its portability and relatively low cost. As the 20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding, as advances in metal coverings (known as [[flux (metallurgy)|flux]]) were made.<ref name="Weman26">Weman, p. 26</ref> Flux covering the electrode primarily shields the base material from impurities, but also stabilizes the arc and can add alloying components to the weld metal.<ref name='ESAB'>{{cite web |title=Lesson 3: Covered Electrodes for Welding Mild Steels |url=http://www.esabna.com/euweb/awtc/lesson3_6.htm |date= |work= |publisher= |accessdate=18 May 2017}}</ref>

[[Image:Maurzyce 2009 (0).jpg|thumb|Bridge of Maurzyce]]
World War I caused a major surge in the use of welding processes, with the various military powers attempting to determine which of the several new welding processes would be best. The British primarily used arc welding, even constructing a ship, the "Fullagar" with an entirely welded hull.<ref>[http://www.weldinghistory.org/whfolder/folder/wh1900.html A History of Welding]. weldinghistory.org</ref><ref>[http://www.gracesguide.co.uk/The_Engineer ''The Engineer''] (6 February 1920) p. 142</ref> Arc welding was first applied to aircraft during the war as well, as some German airplane fuselages were constructed using the process.<ref>Lincoln Electric, p. 1.1–5</ref> Also noteworthy is the first welded road bridge in the world, the [[Maurzyce Bridge]] designed by [[Stefan Bryła]] of the [[Lwów University of Technology]] in 1927, and built across the river [[Słudwia River|Słudwia]] near [[Łowicz]], Poland in 1928.<ref>{{cite web|url=http://www.weldinghistory.org/whistoryfolder/welding/wh_1900-1950.html |title=Welding Timeline 1900–1950 |last=Sapp |first=Mark E. |date=February 22, 2008 |publisher=WeldingHistory.org |accessdate=2008-04-29 |deadurl=yes |archiveurl=https://web.archive.org/web/20080803060938/http://www.weldinghistory.org/whistoryfolder/welding/wh_1900-1950.html |archivedate=August 3, 2008 }}</ref>
[[File:Acetylene welding on cylinder water jacket., 1918 - NARA - 530779.tif|thumb|left|170px|Acetylene welding on cylinder water jacket, US Army 1918]]
During the 1920s, major advances were made in welding technology, including the introduction of automatic welding in 1920, in which electrode wire was fed continuously. [[Shielding gas]] became a subject receiving much attention, as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems, and the solutions that developed included the use of [[hydrogen]], [[argon]], and [[helium]] as welding atmospheres.<ref>{{harvnb|Cary|Helzer|2005|p=7}}</ref> During the following decade, further advances allowed for the welding of reactive metals like [[aluminium|aluminum]] and [[magnesium]]. This in conjunction with developments in automatic welding, alternating current, and fluxes fed a major expansion of arc welding during the 1930s and then during World War II.<ref>Lincoln Electric, p. 1.1–6</ref> In 1930, the first all-welded merchant vessel, [[M/S Carolinian]], was launched.

During the middle of the century, many new welding methods were invented. In 1930, Kyle Taylor was responsible for the release of [[stud welding]], which soon became popular in shipbuilding and construction. Submerged arc welding was invented the same year and continues to be popular today. In 1932 a Russian, [[Konstantin Khrenov]] successfully implemented the first underwater electric arc welding. [[Gas tungsten arc welding]], after decades of development, was finally perfected in 1941, and gas metal arc welding followed in 1948, allowing for fast welding of non-[[ferrous]] materials but requiring expensive shielding gases. Shielded metal arc welding was developed during the 1950s, using a flux-coated consumable electrode, and it quickly became the most popular metal arc welding process. In 1957, the flux-cored arc welding process debuted, in which the self-shielded wire electrode could be used with automatic equipment, resulting in greatly increased welding speeds, and that same year, [[plasma arc welding]] was invented. Electroslag welding was introduced in 1958, and it was followed by its cousin, [[electrogas welding]], in 1961.<ref>{{harvnb|Cary|Helzer|2005|p=9}}</ref> In 1953, the Soviet scientist N. F. Kazakov proposed the [[diffusion welding|diffusion bonding]] method.<ref>{{cite web|url=http://www.msm.cam.ac.uk/phase-trans/2005/Amir/bond.html |title=Diffusion Bonding of Materials |last=Kazakov |first=N.F |year=1985 |publisher=University of Cambridge |accessdate=2011-01-13 |deadurl=yes |archiveurl=http://www.webcitation.org/5nUYH5lQv?url=http://www.msm.cam.ac.uk/phase-trans/2005/Amir/bond.html |archivedate=2010-02-12 |df= }}</ref>

Other recent developments in welding include the 1958 breakthrough of electron beam welding, making deep and narrow welding possible through the concentrated heat source. Following the invention of the laser in 1960, laser beam welding debuted several decades later, and has proved to be especially useful in high-speed, automated welding. [[Magnetic pulse welding]] (MPW) is industrially used since 1967. [[Friction stir welding]] was invented in 1991 by Wayne Thomas at [[The Welding Institute]] (TWI, UK) and found high-quality applications all over the world.<ref>{{cite book|author=Mel Schwartz|title=Innovations in Materials Manufacturing, Fabrication, and Environmental Safety|url=https://books.google.com/books?id=rpCs0AoQOBoC&pg=PA300|accessdate=10 July 2012|date=2011|publisher=CRC Press|isbn=978-1-4200-8215-9|pages=300–}}</ref> All of these four new processes continue to be quite expensive due the high cost of the necessary equipment, and this has limited their applications.<ref>Lincoln Electric, pp. 1.1–10</ref>

==Processes==

===Arc===
{{Main article|Arc welding}}
[[File:Man welding a metal structure in a newly constructed house in Bengaluru, India.webm|thumb|Man welding a metal structure in a newly constructed house in Bengaluru, India]]
These processes use a [[welding power supply]] to create and maintain an electric arc between an electrode and the base material to melt metals at the welding point. They can use either [[direct current|direct]] (DC) or alternating (AC) current, and consumable or non-consumable [[electrode]]s. The welding region is sometimes protected by some type of inert or semi-[[inert gas]], known as a shielding gas, and filler material is sometimes used as well.

====Power supplies====
To supply the electrical power necessary for arc welding processes, a variety of different power supplies can be used. The most common welding power supplies are constant [[electrical current|current]] power supplies and constant [[voltage]] power supplies. In arc welding, the length of the arc is directly related to the voltage, and the amount of heat input is related to the current. Constant current power supplies are most often used for manual welding processes such as gas tungsten arc welding and shielded metal arc welding, because they maintain a relatively constant current even as the voltage varies. This is important because in manual welding, it can be difficult to hold the electrode perfectly steady, and as a result, the arc length and thus voltage tend to fluctuate. Constant voltage power supplies hold the voltage constant and vary the current, and as a result, are most often used for automated welding processes such as gas metal arc welding, flux cored arc welding, and submerged arc welding. In these processes, arc length is kept constant, since any fluctuation in the distance between the wire and the base material is quickly rectified by a large change in current. For example, if the wire and the base material get too close, the current will rapidly increase, which in turn causes the heat to increase and the tip of the wire to melt, returning it to its original separation distance.<ref>{{harvnb|Cary|Helzer|2005|pp=246–249}}</ref>

The type of current used plays an important role in arc welding. Consumable electrode processes such as shielded metal arc welding and gas metal arc welding generally use direct current, but the electrode can be charged either positively or negatively. In welding, the positively charged [[anode]] will have a greater heat concentration, and as a result, changing the polarity of the electrode affects weld properties. If the electrode is positively charged, the base metal will be hotter, increasing weld penetration and welding speed. Alternatively, a negatively charged electrode results in more shallow welds.<ref>Kalpakjian and Schmid, p. 780</ref> Nonconsumable electrode processes, such as gas tungsten arc welding, can use either type of direct current, as well as alternating current. However, with direct current, because the electrode only creates the arc and does not provide filler material, a positively charged electrode causes shallow welds, while a negatively charged electrode makes deeper welds.<ref>Lincoln Electric, p. 5.4–5</ref> Alternating current rapidly moves between these two, resulting in medium-penetration welds. One disadvantage of AC, the fact that the arc must be re-ignited after every zero crossing, has been addressed with the invention of special power units that produce a [[square wave]] pattern instead of the normal [[sine wave]], making rapid zero crossings possible and minimizing the effects of the problem.<ref>Weman, p. 16</ref>

====Processes====
One of the most common types of arc welding is [[shielded metal arc welding]] (SMAW);<ref name="Weman63">Weman, p. 63</ref> it is also known as manual metal arc welding (MMA) or stick welding. Electric current is used to strike an arc between the base material and consumable electrode rod, which is made of filler material (typically steel) and is covered with a flux that protects the weld area from [[redox|oxidation]] and contamination by producing [[carbon dioxide]] (CO2) gas during the welding process. The electrode core itself acts as filler material, making a separate filler unnecessary.<ref name="Weman63" />

[[Image:US Navy 090114-N-9704L-004 Hull Technician Fireman John Hansen lays beads for welding qualifications.jpg|thumb|left|Shielded metal arc welding]]

The process is versatile and can be performed with relatively inexpensive equipment, making it well suited to shop jobs and field work.<ref name="Weman63" /><ref name="Cary103">{{harvnb|Cary|Helzer|2005|p=103}}</ref> An operator can become reasonably proficient with a modest amount of training and can achieve mastery with experience. Weld times are rather slow, since the consumable electrodes must be frequently replaced and because slag, the residue from the flux, must be chipped away after welding.<ref name="Weman63" /> Furthermore, the process is generally limited to welding ferrous materials, though special electrodes have made possible the welding of [[cast iron]], [[nickel]], aluminum, [[copper]], and other metals.<ref name="Cary103" />
[[Image:SMAW area diagram.svg|thumb|right|Diagram of arc and weld area, in shielded metal arc welding.
 
1. Coating Flow 
2. Rod 
3. Shield Gas 
4. Fusion 
5. Base metal 
6. Weld metal 
7. Solidified Slag
]]

[[Gas metal arc welding]] (GMAW), also known as metal inert gas or MIG welding, is a semi-automatic or automatic process that uses a continuous wire feed as an electrode and an inert or semi-inert gas mixture to protect the weld from contamination. Since the electrode is continuous, welding speeds are greater for GMAW than for SMAW.<ref name="LE5.43">Lincoln Electric, p. 5.4-3</ref>

A related process, [[flux-cored arc welding]] (FCAW), uses similar equipment but uses wire consisting of a steel electrode surrounding a powder fill material. This cored wire is more expensive than the standard solid wire and can generate fumes and/or slag, but it permits even higher welding speed and greater metal penetration.<ref>Weman, p. 53</ref>

[[Gas tungsten arc welding]] (GTAW), or tungsten inert gas (TIG) welding, is a manual welding process that uses a nonconsumable [[tungsten]] electrode, an inert or semi-inert gas mixture, and a separate filler material.<ref name="Weman31">Weman, p. 31</ref> Especially useful for welding thin materials, this method is characterized by a stable arc and high quality welds, but it requires significant operator skill and can only be accomplished at relatively low speeds.<ref name="Weman31" />

GTAW can be used on nearly all weldable metals, though it is most often applied to [[stainless steel]] and light metals. It is often used when quality welds are extremely important, such as in [[bicycle]], aircraft and naval applications.<ref name="Weman31" /> A related process, plasma arc welding, also uses a tungsten electrode but uses plasma gas to make the arc. The arc is more concentrated than the GTAW arc, making transverse control more critical and thus generally restricting the technique to a mechanized process. Because of its stable current, the method can be used on a wider range of material thicknesses than can the GTAW process and it is much faster. It can be applied to all of the same materials as GTAW except magnesium, and automated welding of stainless steel is one important application of the process. A variation of the process is [[plasma cutting]], an efficient steel cutting process.<ref>Weman, pp. 37–38</ref>

[[Submerged arc welding]] (SAW) is a high-productivity welding method in which the arc is struck beneath a covering layer of flux. This increases arc quality, since contaminants in the atmosphere are blocked by the flux. The slag that forms on the weld generally comes off by itself, and combined with the use of a continuous wire feed, the weld deposition rate is high. Working conditions are much improved over other arc welding processes, since the flux hides the arc and almost no smoke is produced. The process is commonly used in industry, especially for large products and in the manufacture of welded pressure vessels.<ref>Weman, p. 68</ref> Other arc welding processes include [[atomic hydrogen welding]], [[electroslag welding]], [[electrogas welding]], and [[stud arc welding]].<ref>Weman, pp. 93–94</ref>

===Gas welding===
{{main article|Oxy-fuel welding and cutting}}

The most common gas welding process is oxyfuel welding,<ref name="Weman26" /> also known as oxyacetylene welding. It is one of the oldest and most versatile welding processes, but in recent years it has become less popular in industrial applications. It is still widely used for welding pipes and tubes, as well as repair work.<ref name="Weman26" />

The equipment is relatively inexpensive and simple, generally employing the combustion of acetylene in [[oxygen]] to produce a welding flame temperature of about 3100 °C.<ref name="Weman26" /> The flame, since it is less concentrated than an electric arc, causes slower weld cooling, which can lead to greater residual stresses and weld distortion, though it eases the welding of high alloy steels. A similar process, generally called oxyfuel cutting, is used to cut metals.<ref name="Weman26" />

===Resistance===
{{Main article|Resistance welding}}

Resistance welding involves the generation of heat by passing current through the resistance caused by the contact between two or more metal surfaces. Small pools of molten metal are formed at the weld area as high current (1000–100,000 [[Ampere|A]]) is passed through the metal.<ref name="Weman8084">Weman, pp. 80–84</ref> In general, resistance welding methods are efficient and cause little pollution, but their applications are somewhat limited and the equipment cost can be high.<ref name="Weman8084" />

[[Image:Spot welder.miller.triddle.jpg|thumb|Spot welder]]
[[Spot welding]] is a popular resistance welding method used to join overlapping metal sheets of up to 3 mm thick.<ref name="Weman8084" /> Two electrodes are simultaneously used to clamp the metal sheets together and to pass current through the sheets. The advantages of the method include [[efficient energy use]], limited workpiece deformation, high production rates, easy automation, and no required filler materials. Weld strength is significantly lower than with other welding methods, making the process suitable for only certain applications. It is used extensively in the automotive industry—ordinary cars can have several thousand spot welds made by [[industrial robot]]s. A specialized process, called [[shot welding]], can be used to spot weld stainless steel.<ref name="Weman8084" />

Like spot welding, [[seam welding]] relies on two electrodes to apply pressure and current to join metal sheets. However, instead of pointed electrodes, wheel-shaped electrodes roll along and often feed the workpiece, making it possible to make long continuous welds. In the past, this process was used in the manufacture of beverage cans, but now its uses are more limited.<ref name="Weman8084" /> Other resistance welding methods include [[butt welding]],<ref>{{Cite book|author = John Jernberg| title = Forging| page = 26| publisher = American Technical society| year = 1919| url = https://books.google.com/books?id=-ksxAAAAMAAJ&pg=PA26}}</ref> [[flash welding]], [[projection welding]], and [[upset welding]].<ref name="Weman8084" />

===Energy beam===
Energy beam welding methods, namely [[laser beam welding]] and [[electron beam welding]], are relatively new processes that have become quite popular in high production applications. The two processes are quite similar, differing most notably in their source of power. Laser beam welding employs a highly focused laser beam, while electron beam welding is done in a vacuum and uses an electron beam. Both have a very high energy density, making deep weld penetration possible and minimizing the size of the weld area. Both processes are extremely fast, and are easily automated, making them highly productive. The primary disadvantages are their very high equipment costs (though these are decreasing) and a susceptibility to thermal cracking. Developments in this area include [[laser-hybrid welding]], which uses principles from both laser beam welding and arc welding for even better weld properties, [[cladding (metalworking)|laser cladding]], and [[x-ray welding]].<ref>Weman, pp. 95–101</ref>

===Solid-state===
[[File:Solid-state welding processes - AWS A3.0 2001.svg|thumb|300px|right|Solid-state welding processes [[classification chart]]<ref>AWS A3.0:2001, Standard Welding Terms and Definitions Including Terms for Adhesive Bonding, Brazing, Soldering, Thermal Cutting, and Thermal Spraying, American Welding Society (2001), p. 117. {{ISBN|0-87171-624-0}}</ref>]]
Like the first welding process, forge welding, some modern welding methods do not involve the melting of the materials being joined. One of the most popular, [[ultrasonic welding]], is used to connect thin sheets or wires made of metal or thermoplastic by vibrating them at high frequency and under high pressure.<ref name="Weman8990">Weman, pp. 89–90</ref> The equipment and methods involved are similar to that of resistance welding, but instead of electric current, vibration provides energy input. Welding metals with this process does not involve melting the materials; instead, the weld is formed by introducing mechanical vibrations horizontally under pressure. When welding plastics, the materials should have similar melting temperatures, and the vibrations are introduced vertically. Ultrasonic welding is commonly used for making electrical connections out of aluminum or copper, and it is also a very common polymer welding process.<ref name="Weman8990" />

Another common process, [[explosion welding]], involves the joining of materials by pushing them together under extremely high pressure. The energy from the impact plasticizes the materials, forming a weld, even though only a limited amount of heat is generated. The process is commonly used for welding dissimilar materials, such as the welding of aluminum with steel in ship hulls or compound plates.<ref name="Weman8990" /> Other solid-state welding processes include [[friction welding]] (including [[friction stir welding]]),<ref name="NZ">Stephan Kallee (August 2006) [http://www.twi.co.uk/content/spswkaug2006.html "NZ Fabricators begin to use Friction Stir Welding to produce aluminium components and panels"] {{webarchive |url=https://web.archive.org/web/20100316134257/http://www.twi.co.uk/content/spswkaug2006.html |date=March 16, 2010 }}. ''New Zealand Engineering News''.</ref> [[magnetic pulse welding]],<ref name="EMPT">Stephan Kallee et al. (2010) ''[http://www.msm.cam.ac.uk/phase-trans/2010/IPM.pdf Industrialisation of Electromagnetic Pulse Technology (EMPT) in India]'' 38th Anniversary Issue of PURCHASE India.</ref> co-extrusion welding, [[cold welding]], [[diffusion bonding]], [[exothermic welding]], [[high frequency welding]], hot pressure welding, [[induction welding]], and [[Cladding (metalworking)|roll welding]].<ref name="Weman8990" />

==Geometry==
{{Main article|Welding joint}}
[[Image:Common Joint Types ZP.svg|left|thumb|Common welding joint types – (1) Square butt joint, (2) V butt joint, (3) Lap joint, (4) T-joint]]

Welds can be geometrically prepared in many different ways. The five basic types of weld joints are the butt joint, lap joint, corner joint, edge joint, and T-joint (a variant of this last is the [[cruciform joint]]). Other variations exist as well—for example, double-V preparation joints are characterized by the two pieces of material each tapering to a single center point at one-half their height. Single-U and double-U preparation joints are also fairly common—instead of having straight edges like the single-V and double-V preparation joints, they are curved, forming the shape of a U. Lap joints are also commonly more than two pieces thick—depending on the process used and the thickness of the material, many pieces can be welded together in a lap joint geometry.<ref>{{Cite book
| last = Hicks
| first = John
| year = 1999
| title = Welded Joint Design
| location = [[New York City|New York]]
| publisher = Industrial Press
| isbn = 0-8311-3130-6 | pages=52–55
}}</ref>

Many welding processes require the use of a particular joint design; for example, resistance spot welding, laser beam welding, and electron beam welding are most frequently performed on lap joints. Other welding methods, like shielded metal arc welding, are extremely versatile and can weld virtually any type of joint. Some processes can also be used to make multipass welds, in which one weld is allowed to cool, and then another weld is performed on top of it. This allows for the welding of thick sections arranged in a single-V preparation joint, for example.<ref>{{harvnb|Cary|Helzer|2005|pp=19, 103, 206}}</ref>

[[Image:Welded butt joint x-section.svg|thumb|The cross-section of a welded butt joint, with the darkest gray representing the weld or fusion zone, the medium gray the heat-affected zone, and the lightest gray the base material.]]
After welding, a number of distinct regions can be identified in the weld area. The weld itself is called the fusion zone—more specifically, it is where the filler metal was laid during the welding process. The properties of the fusion zone depend primarily on the filler metal used, and its compatibility with the base materials. It is surrounded by the [[heat-affected zone]], the area that had its microstructure and properties altered by the weld. These properties depend on the base material's behavior when subjected to heat. The metal in this area is often weaker than both the base material and the fusion zone, and is also where residual stresses are found.<ref>{{harvnb|Cary|Helzer|2005|pp=401–404}}</ref>

==Quality==
{{main article|Weld quality assurance}}
[[Image:Pipe root weld with HAZ.jpg|thumb|The blue area results from oxidation at a corresponding temperature of {{convert|600|°F|°C|abbr=on}}. This is an accurate way to identify temperature, but does not represent the HAZ width. The HAZ is the narrow area that immediately surrounds the welded base metal.]]

Many distinct factors influence the strength of welds and the material around them, including the welding method, the amount and concentration of energy input, the [[weldability]] of the base material, filler material, and flux material, the design of the joint, and the interactions between all these factors.<ref name="Weman6062">Weman, pp. 60–62</ref> To test the quality of a weld, either [[destructive testing|destructive]] or [[nondestructive testing]] methods are commonly used to verify that welds are free of defects, have acceptable levels of residual stresses and distortion, and have acceptable heat-affected zone (HAZ) properties. Types of [[welding defect]]s include cracks, distortion, gas inclusions (porosity), non-metallic inclusions, lack of fusion, incomplete penetration, lamellar tearing, and undercutting.

The metalworking industry has instituted [[List of welding codes|specifications and codes]] to guide [[welders]], [[weld inspectors]], [[engineers]], managers, and property owners in proper welding technique, design of welds, how to judge the quality of [[Welding Procedure Specification]], how to judge the skill of the person performing the weld, and how to ensure the quality of a welding job.<ref name="Weman6062" /> Methods such as [[visual inspection]], [[radiography]], [[ultrasonic testing]], [[phased-array ultrasonics]], [[dye penetrant inspection]], [[magnetic particle inspection]], or [[industrial computed tomography]] can help with detection and analysis of certain defects.

===Heat-affected zone===
The heat-affected zone (HAZ) is a ring surrounding the weld in which the temperature of the welding process, combined with the stresses of uneven heating and cooling, alter the [[heat-treatment]] properties of the alloy. The effects of welding on the material surrounding the weld can be detrimental—depending on the materials used and the heat input of the welding process used, the HAZ can be of varying size and strength. The [[thermal diffusivity]] of the base material plays a large role—if the diffusivity is high, the material cooling rate is high and the HAZ is relatively small. Conversely, a low diffusivity leads to slower cooling and a larger HAZ. The amount of heat injected by the welding process plays an important role as well, as processes like oxyacetylene welding have an unconcentrated heat input and increase the size of the HAZ. Processes like laser beam welding give a highly concentrated, limited amount of heat, resulting in a small HAZ. Arc welding falls between these two extremes, with the individual processes varying somewhat in heat input.<ref>Lincoln Electric, pp. 6.1-5–6.1–6</ref><ref>Kalpakjian and Schmid, pp. 821–22</ref> To calculate the heat input for arc welding procedures, the following formula can be used:

:<math>Q = \left(\frac{V \times I \times 60}{S \times 1000} \right) \times
\mathit{Efficiency}</math>

where ''Q'' = heat input ([[kilojoule|kJ]]/mm), ''V'' = voltage ([[Volt|V]]), ''I'' = current (A), and ''S'' = welding speed (mm/min). The efficiency is dependent on the welding process used, with shielded metal arc welding having a value of 0.75, gas metal arc welding and submerged arc welding, 0.9, and gas tungsten arc welding, 0.8.<ref>Weman, p. 5</ref> Methods of alleviating the stresses and brittleness created in the HAZ include [[Heat treating#Stress relieving|stress relieving]] and [[Tempering (metallurgy)#Welded steel|tempering]].<ref>''How To Weld'' By Todd Bridigum - Motorbook 2008 Page 37</ref>

===Lifetime extension with aftertreatment methods===
[[Image:Example HiFIT-treated assembly.jpg|thumb|left|Example: High Frequency Impact Treatment for lifetime extension]]
The durability and life of dynamically loaded, welded steel structures is determined in many cases by the welds, in particular the weld transitions. Through selective treatment of the transitions by [[grinding (abrasive cutting)]], [[shot peening]], [[High Frequency Impact Treatment]], etc. the durability of many designs increase significantly.

==Metallurgy==

Most solids used are engineering materials consisting of crystalline solids in which the atoms or ions are arranged in a repetitive geometric pattern which is known as a [[lattice structure]]. The only exception is material that is made from glass which is a combination of a supercooled liquid and polymers which are aggregates of large organic molecules.<ref name = "Lancaster">{{cite book|last=Lancaster|first=J.F.|title=Metallurgy of welding|year=1999|publisher=Abington Pub.|location=Abington, Cambridge|isbn=1-85573-428-1|edition=6th}}</ref>

Crystalline solids cohesion is obtained by a metallic or chemical bond which is formed between the constituent atoms. Chemical bonds can be grouped into two types consisting of [[ionic bond|ionic]] and [[covalent]]. To form an ionic bond, either a [[valence (chemistry)|valence]] or [[chemical bond|bond]]ing electron separates from one atom and becomes attached to another atom to form oppositely charged [[ions]]. The bonding in the static position is when the ions occupy an equilibrium position where the resulting force between them is zero. When the ions are exerted in [[tension (physics)|tension]] force, the inter-ionic spacing increases creating an electrostatic attractive force, while a repulsing force under [[compressive]] force between the atomic nuclei is dominant.<ref name = "Lancaster" />

Covalent bonding takes place when one of the constituent atoms loses one or more electrons, with the other atom gaining the electrons, resulting in an electron cloud that is shared by the molecule as a whole. In both ionic and covalent bonding the location of the ions and electrons are constrained relative to each other, thereby resulting in the bond being characteristically [[brittle]].<ref name = "Lancaster" />

[[Metallic bonding]] can be classified as a type of covalent bonding for which the constituent atoms of the same type and do not combine with one another to form a chemical bond. Atoms will lose an electron(s) forming an array of positive ions. These electrons are shared by the lattice which makes the electron cluster mobile, as the electrons are free to move as well as the ions. For this, it gives metals their relatively high thermal and electrical conductivity as well as being characteristically [[ductile]].<ref name = "Lancaster" />

Three of the most commonly used crystal lattice structures in metals are the [[body-centred cubic]], [[face-centred cubic]] and [[close-packing of equal spheres|close-packed hexagonal]]. Ferritic [[steel]] has a body-centred cubic structure and [[austenitic steel]], [[non-ferrous metals]] like [[aluminium|aluminum]], [[copper]] and [[nickel]] have the face-centred cubic structure.<ref name = "Lancaster" />

Ductility is an important factor in ensuring the integrity of structures by enabling them to sustain local stress concentrations without fracture. In addition, structures are required to be of an acceptable strength, which is related to a material's [[yield strength]]. In general, as the yield strength of a material increases, there is a corresponding reduction in [[fracture toughness]].<ref name = "Lancaster" />

A reduction in fracture toughness may also be attributed to the embrittlement effect of impurities, or for body-centred cubic metals, from a reduction in temperature. Metals and in particular steels have a transitional temperature range where above this range the metal has acceptable notch-ductility while below this range the material becomes brittle. Within the range, the materials behavior is unpredictable. The reduction in fracture toughness is accompanied by a change in the fracture appearance. When above the transition, the fracture is primarily due to micro-void coalescence, which results in the fracture appearing [[Fiber|fibrous]]. When the temperatures falls the fracture will show signs of cleavage facets. These two appearances are visible by the naked eye. Brittle fracture in steel plates may appear as chevron markings under the [[microscope]]. These arrow-like ridges on the crack surface point towards the origin of the fracture.<ref name = "Lancaster" />

Fracture toughness is measured using a notched and pre-cracked rectangular specimen, of which the dimensions are specified in standards, for example ASTM E23. There are other means of estimating or measuring fracture toughness by the following: The Charpy impact test per ASTM A370; The crack-tip opening displacement (CTOD) test per BS 7448-1; The J integral test per ASTM E1820; The Pellini drop-weight test per ASTM E208.<ref name = "Lancaster" />

==Unusual conditions==
[[File:Working Diver 01.jpg|thumb|left|Underwater welding]]

While many welding applications are done in controlled environments such as factories and repair shops, some welding processes are commonly used in a wide variety of conditions, such as open air, underwater, and [[vacuum]]s (such as space). In open-air applications, such as construction and outdoors repair, shielded metal arc welding is the most common process. Processes that employ inert gases to protect the weld cannot be readily used in such situations, because unpredictable atmospheric movements can result in a faulty weld. Shielded metal arc welding is also often used in underwater welding in the construction and repair of ships, offshore platforms, and pipelines, but others, such as flux cored arc welding and gas tungsten arc welding, are also common. Welding in space is also possible—it was first attempted in 1969 by [[Russia]]n cosmonauts, when they performed experiments to test shielded metal arc welding, plasma arc welding, and electron beam welding in a depressurized environment. Further testing of these methods was done in the following decades, and today researchers continue to develop methods for using other welding processes in space, such as laser beam welding, resistance welding, and friction welding. Advances in these areas may be useful for future endeavours similar to the construction of the [[International Space Station]], which could rely on welding for joining in space the parts that were manufactured on Earth.<ref>{{harvnb|Cary|Helzer|2005|pp=677–683}}</ref>

==Safety issues==
[[Image:AlfredPalmerwelder1.jpg|thumb|Arc welding with a welding helmet, gloves, and other protective clothing]]

Welding can be dangerous and unhealthy if the proper precautions are not taken. However, using new technology and proper protection greatly reduces risks of injury and death associated with welding.<ref>ANSI/AWS Z49.1: "Safety in Welding, Cutting, and Allied Processes" (2005)</ref> Since many common welding procedures involve an open electric arc or flame, the risk of burns and fire is significant; this is why it is classified as a [[hot work]] process. To prevent injury, [[welder]]s wear [[personal protective equipment]] in the form of heavy [[leather]] [[glove]]s and protective long-sleeve jackets to avoid exposure to extreme heat and flames. Additionally, the brightness of the weld area leads to a condition called [[arc eye]] or flash burns in which ultraviolet light causes inflammation of the [[cornea]] and can burn the [[retina]]s of the eyes. [[Goggle]]s and [[welding helmet]]s with dark UV-filtering face plates are worn to prevent this exposure. Since the 2000s, some helmets have included a face plate which instantly darkens upon exposure to the intense UV light. To protect bystanders, the welding area is often surrounded with translucent welding curtains. These curtains, made of a [[polyvinyl chloride]] plastic film, shield people outside the welding area from the UV light of the electric arc, but can not replace the [[filter (optics)|filter]] glass used in helmets.<ref>{{harvnb|Cary|Helzer|2005|pp=42, 49–51}}</ref>

[[File:Chamber for Welding Fumes (8743403735).jpg|thumb|left|A chamber designed to contain welding fumes for analysis]]
[[File:Welding Helmet Effects on Breathing Zone Exposures.webm|thumb|A video describing research on welding helmets and their ability to limit fume exposure]]
Welders are often exposed to dangerous gases and [[Particle|particulate]] matter. Processes like flux-cored arc welding and shielded metal arc welding produce [[smoke]] containing particles of various types of [[oxide]]s. The size of the particles in question tends to influence the [[toxicity]] of the fumes, with smaller particles presenting a greater danger. This is because smaller particles have the ability to cross the [[blood brain barrier]]. Fumes and gases, such as carbon dioxide, [[ozone]], and fumes containing [[heavy metals]], can be dangerous to welders lacking proper ventilation and training.<ref name="Cary5262">{{harvnb|Cary|Helzer|2005|pp=52–62}}</ref> Exposure to [[manganese]] welding fumes, for example, even at low levels (<0.2 mg/m3), may lead to neurological problems or to damage to the lungs, liver, kidneys, or central nervous system.<ref>[http://www.cdc.gov/niosh/topics/welding/ Welding and Manganese: Potential Neurologic Effects]. The inhalation of nano particles National Institute for Occupational Safety and Health. March 30, 2009.</ref> Nano particles can become trapped in the alveolar macrophages of the lungs and induce pulmonary fibrosis.<ref>{{cite journal|title=The significance of nano particles in particle-induced pulmonary fibrosis|author1=James D Byrne|author2=John A Baugh|journal=McGill Journal of Medicine|date=2008|volume=11|pages=43–50|pmc=2322933|pmid=18523535|issue=1}}</ref> The use of compressed gases and flames in many welding processes poses an explosion and fire risk. Some common precautions include limiting the amount of oxygen in the air, and keeping combustible materials away from the workplace.<ref name="Cary5262" />

==Costs and trends==
As an industrial process, the cost of welding plays a crucial role in manufacturing decisions. Many different variables affect the total cost, including equipment cost, labor cost, material cost, and [[electric power|energy]] cost.<ref name="Weman18489">Weman, pp. 184–89</ref> Depending on the process, equipment cost can vary, from inexpensive for methods like [[shielded metal arc welding]] and [[oxyfuel welding]], to extremely expensive for methods like laser beam welding and electron beam welding. Because of their high cost, they are only used in high production operations. Similarly, because automation and robots increase equipment costs, they are only implemented when high production is necessary. Labor cost depends on the deposition rate (the rate of welding), the hourly wage, and the total operation time, including time spent fitting, welding, and handling the part. The cost of materials includes the cost of the base and filler material, and the cost of shielding gases. Finally, energy cost depends on arc time and welding power demand.<ref name="Weman18489" />

For manual welding methods, labor costs generally make up the vast majority of the total cost. As a result, many cost-saving measures are focused on minimizing operation time. To do this, welding procedures with high deposition rates can be selected, and weld parameters can be fine-tuned to increase welding speed. Mechanization and automation are often implemented to reduce labor costs, but this frequently increases the cost of equipment and creates additional setup time. Material costs tend to increase when special properties are necessary, and energy costs normally do not amount to more than several percent of the total welding cost.<ref name="Weman18489" />

In recent years, in order to minimize labor costs in high production manufacturing, industrial welding has become increasingly more automated, most notably with the use of robots in resistance spot welding (especially in the automotive industry) and in arc welding. In robot welding, mechanized devices both hold the material and perform the weld<ref>Lincoln Electric, p. 4.5-1</ref> and at first, spot welding was its most common application, but robotic arc welding increases in popularity as technology advances. Other key areas of research and development include the welding of dissimilar materials (such as steel and aluminum, for example) and new welding processes, such as friction stir, magnetic pulse, conductive heat seam, and laser-hybrid welding. Furthermore, progress is desired in making more specialized methods like laser beam welding practical for more applications, such as in the aerospace and automotive industries. Researchers also hope to better understand the often unpredictable properties of welds, especially microstructure, [[residual stress]]es, and a weld's tendency to crack or deform.<ref name="ASM International">{{Cite book
| author = ASM International
| year = 2003
| title = Trends in Welding Research
| location = Materials Park, Ohio
| publisher = ASM International
| isbn = 0-87170-780-2 | pages=995–1005
}}</ref>

The trend of accelerating the speed at which welds are performed in the [[steel erector|steel erection]] industry comes at a risk to the integrity of the connection. Without proper fusion to the base materials provided by sufficient arc time on the weld, a project inspector cannot ensure the effective diameter of the puddle weld therefore he or she cannot guarantee the published load capacities unless they witness the actual installation.<ref>Gregory L. Snow and W. Samuel Easterling (October 2008) [http://www.us.hilti.com/fstore/holus/LinkFiles/19th_Int_SCCFSS_1.pdf Strength of Arc Spot Welds Made in Single and Multiple Steel Sheets], Proceedings of the 19th International Specialty Conference on Cold-Formed Steel Structures, Missouri University of Science and Technology.</ref> This method of puddle welding is common in the United States and Canada for attaching steel sheets to [[bar joist]] and [[structural steel]] members. Regional agencies are responsible for ensuring the proper installation of puddle welding on steel construction sites. Currently there is no standard or weld procedure which can ensure the published holding capacity of any unwitnessed connection, but this is under review by the [[American Welding Society]].

==Glass and plastic welding==
[[File:Glass welding two tubes together.JPG|thumb|The welding together of two tubes made from lead glass]]
[[File:Cast glass bowl showing the weld seam.JPG|thumb|A bowl made from cast-glass. The two halves are joined together by the weld seam, running down the middle.]]

Glasses and certain types of plastics are commonly welded materials. Unlike metals, which have a specific [[melting point]], glasses and plastics have a melting range, called the [[glass transition]]. When heating the solid material into this range, it will generally become softer and more pliable. When it crosses through the glass transition, it will become a very thick, sluggish, viscous liquid. Typically, this [[viscous liquid]] will have very little [[surface tension]], becoming a sticky, honey-like consistency, so welding can usually take place by simply pressing two melted surfaces together. The two liquids will generally mix and join at first contact. Upon cooling through the glass transition, the welded piece will solidify as one solid piece of [[amorphous solid|amorphous material]].

===Glass welding===
{{main article|Glassblowing}}

Glass welding is a common practice during glassblowing. It is used very often in the construction of lighting, [[neon sign]]s, [[flashtube]]s, scientific equipment, and the manufacture of dishes and other glassware. It is also used during [[glass casting]] for joining the halves of glass molds, making items such as bottles and jars. Welding glass is accomplished by heating the glass through the glass transition, turning it into a thick, formable, liquid mass. Heating is usually done with a gas or oxy-gas torch, or a furnace, because the temperatures for melting glass are often quite high. This temperature may vary, depending on the type of glass. For example, [[lead glass]] becomes a weldable liquid at around {{convert|1600|F|C}}, and can be welded with a simple propane torch. On the other hand, quartz glass ([[fused silica]]) must be heated to over {{convert|3000|F|C}}, but quickly loses its viscosity and formability if overheated, so an [[oxyhydrogen]] torch must be used. Sometimes a tube may be attached to the glass, allowing it to be blown into various shapes, such as bulbs, bottles, or tubes. When two pieces of liquid glass are pressed together, they will usually weld very readily. Welding a handle onto a pitcher can usually be done with relative ease. However, when welding a tube to another tube, a combination of blowing and suction, and pressing and pulling is used to ensure a good seal, to shape the glass, and to keep the surface tension from closing the tube in on itself. Sometimes a filler rod may be used, but usually not.

Because glass is very brittle in its solid state, it is often prone to cracking upon heating and cooling, especially if the heating and cooling are uneven. This is because the brittleness of glass does not allow for uneven [[thermal expansion]]. Glass that has been welded will usually need to be cooled very slowly and evenly through the glass transition, in a process called [[annealing (glass)|annealing]], to relieve any internal stresses created by a [[temperature gradient]].

There are many types of glass, and it is most common to weld using the same types. Different glasses often have different rates of thermal expansion, which can cause them to crack upon cooling when they contract differently. For instance, quartz has very low thermal expansion, while [[soda-lime glass]] has very high thermal expansion. When welding different glasses to each other, it is usually important to closely match their coefficients of thermal expansion, to ensure that cracking does not occur. Also, some glasses will simply not mix with others, so welding between certain types may not be possible.

Glass can also be welded to metals and ceramics, although with metals the process is usually more adhesion to the surface of the metal rather than a commingling of the two materials. However, certain glasses will typically bond only to certain metals. For example, lead glass bonds readily to [[copper]] or [[molybdenum]], but not to aluminum. [[Tungsten]] electrodes are often used in lighting but will not bond to quartz glass, so the tungsten is often wetted with molten [[borosilicate glass]], which bonds to both tungsten and quartz. However, care must be taken to ensure that all materials have similar coefficients of thermal expansion to prevent cracking both when the object cools and when it is heated again. Special [[alloy]]s are often used for this purpose, ensuring that the coefficients of expansion match, and sometimes thin, metallic coatings may be applied to a metal to create a good bond with the glass.<ref>Freek Bos, Christian Louter, Fred Veer (2008) ''Challenging Glass: Conference on Architectural and Structural Applications''. JOS Press. p. 194. {{ISBN|1586038664}}</ref><ref>Bernard D. Bolas (1921) [https://archive.org/details/handbookoflabora02bolarich ''A handbook of laboratory glassblowing'']. London, G. Routledge and sons</ref>

===Plastic welding===
{{main article|Plastic welding}}

Plastics are generally divided into two categories, which are "thermosets" and "thermoplastics." A [[thermoset]] is a plastic in which a chemical reaction sets the molecular bonds after first forming the plastic, and then the bonds cannot be broken again without degrading the plastic. Thermosets cannot be melted, therefore, once a thermoset has set it is impossible to weld it. Examples of thermosets include [[epoxy|epoxies]], [[silicone]], [[vulcanized rubber]], [[polyester]], and [[polyurethane]].

[[Thermoplastic]]s, by contrast, form long molecular chains, which are often coiled or intertwined, forming an amorphous structure without any long-range, crystalline order. Some thermoplastics may be fully amorphous, while others have a partially crystalline/partially amorphous structure. Both amorphous and semicrystalline thermoplastics have a glass transition, above which welding can occur, but semicrystallines also have a specific melting point which is above the glass transition. Above this melting point, the viscous liquid will become a free-flowing liquid (see [[rheological weldability]] for [[thermoplastics]]). Examples of thermoplastics include [[polyethylene]], [[polypropylene]], [[polystyrene]], [[polyvinylchloride]] (PVC), and fluoroplastics like [[Teflon]] and [[Spectralon]].

Welding thermoplastic is very similar to welding glass. The plastic first must be cleaned and then heated through the glass transition, turning the weld-interface into a thick, viscous liquid. Two heated interfaces can then be pressed together, allowing the molecules to mix through intermolecular diffusion, joining them as one. Then the plastic is cooled through the glass transition, allowing the weld to solidify. A filler rod may often be used for certain types of joints. The main differences between welding glass and plastic are the types of heating methods, the much lower melting temperatures, and the fact that plastics will burn if overheated. Many different methods have been devised for heating plastic to a weldable temperature without burning it. Ovens or electric heating tools can be used to melt the plastic. Ultrasonic, laser, or friction heating are other methods. Resistive metals may be implanted in the plastic, which respond to induction heating. Some plastics will begin to burn at temperatures lower than their glass transition, so welding can be performed by blowing a heated, inert gas onto the plastic, melting it while, at the same time, shielding it from oxygen.<ref>''Plastics and Composites: Welding Handbook'' By David A. Grewell, A. Benatar, Joon Bu Park – Hanser Gardener 2003</ref>

Many thermoplastics can also be welded using chemical [[solvent]]s. When placed in contact with the plastic, the solvent will begin to soften it, bringing the surface into a thick, liquid solution. When two melted surfaces are pressed together, the molecules in the solution mix, joining them as one. Because the solvent can permeate the plastic, the solvent evaporates out through the surface of the plastic, causing the weld to drop out of solution and solidify. A common use for solvent welding is for joining PVC or ABS ([[acrylonitrile butadiene styrene]]) pipes during [[plumbing]], or for welding [[styrene]] and polystyrene plastics in the construction of [[physical model|models]]. Solvent welding is especially effective on plastics like PVC which burn at or below their glass transition, but may be ineffective on plastics like Teflon or polyethylene that are resistant to [[chemical decomposition]].<ref>''Handbook of Plastics Joining: A Practical Guide'' By Plastics Design Library – PDL 1997 Page 137, 146</ref>

==See also==
*[[List of welding codes]]
*[[List of welding processes]]
*[[Regulated Metal Deposition]]
*[[Welding Procedure Specification]]
*[[Welder certification]]
*[[Welded sculpture]]

==Notes==
{{Reflist|30em}}

==References==
*{{Cite book
| last = Cary
| first = Howard B
| first2=Scott C. |last2=Helzer
| year = 2005
| title = Modern Welding Technology
| location = Upper Saddle River, [[New Jersey]]
| publisher = Pearson Education
| isbn = 0-13-113029-3
| ref=harv
}}
*{{Cite book
| last = Kalpakjian
| first = Serope
|author2=Steven R. Schmid
| year = 2001
| title = Manufacturing Engineering and Technology
| publisher = Prentice Hall
| isbn = 0-201-36131-0
}}
*{{Cite book
| author = Lincoln Electric
| year = 1994
| title = The Procedure Handbook of Arc Welding
| location = [[Cleveland]]
| publisher = Lincoln Electric
| isbn = 99949-25-82-2
| authorlink = Lincoln Electric
}}
*{{Cite book
| last = Weman
| first = Klas
| year = 2003
| title = Welding processes handbook
| location = New York, NY
| publisher = CRC Press LLC
| isbn = 0-8493-1773-8
}}

==External links==
{{Commons|Welding}}
*{{dmoz|Science/Technology/Welding}}

{{Metalworking navbox|weldopen}}
{{Machine and metalworking tools}}

{{Authority control}}

[[Category:Welding| ]]
[[Category:IARC Group 2B carcinogens]]
[[Category:Articles containing video clips]]
[[Category:Joining]]
[[Category:Mechanical engineering]]

== Jim Vickers rating ==
1/5 Jims
{{Active Maps Navbox}}{{All Maps Navbox|y}}

Granary Pro

2017-08-09T21:25:40Z

81.147.69.112:

[[File:Zaprice One cell granary 03.JPG|thumb|A simple granary]]
[[File:Chest and Lid with Model Granaries.jpg|thumb|[[Ancient Greek]] [[geometric art]] box in the shape of granaries, 850 BC. On display in the Ancient Agora Museum in Athens, housed in the [[Stoa of Attalos]].]]
[[File:Leuit os 080815-2283 srna.jpg|thumb|right|Leuit, [[Sundanese people|Sundanese]] traditional granary, in [[West Java]], Indonesia.]]
[[File:Kashan granary Barry Kent.JPG|thumb|Granary in [[Kashan]], Iran]]
[[File:Bydgoszcz Spichrze.jpg|thumb|A big granary in [[Bydgoszcz]], Poland, on the [[Brda (river)|Brda river]].]]

{{about|granaries in general|the [[Bristol]] granary|Granary, Bristol|the record label|Granary Music}}
{{lead too short|date=December 2015}}
A '''granary''' is a storehouse or room in a [[barn]] for [[threshing|threshed]] [[cereal|grain]] or [[compound feed|animal feed]]. Ancient or primitive granaries are most often made out of [[pottery]]. Granaries are often built above the ground to keep the stored food away from mice and other animals.

==Early origins==
From ancient times grain has been stored in bulk. The oldest granaries yet found date back to [[10th millennium BC|9500 BC]]<ref name="PNAS09">{{Cite journal | date=Jun 2009 | pages = 10966–10970| issn = 0027-8424| last1 = Kuijt | doi = 10.1073/pnas.0812764106 | pmc = 2700141 | pmid = 19549877| issue = 27 | volume = 106 | title = Evidence for food storage and predomestication granaries 11,000 years ago in the Jordan Valley | first2 = B.| url = http://www.pnas.org/cgi/pmidlookup?view=long&pmid=19549877 | format = Free full text | journal = Proceedings of the National Academy of Sciences of the United States of America| last2 = Finlayson| first1 = I.|bibcode = 2009PNAS..10610966K }}</ref> and are located in the [[Pre-Pottery Neolithic A]] settlements in the [[Jordan River|Jordan Valley]]. The first were located in places between other buildings. However beginning around [[9th millennium BC|8500 BC]], they were moved inside houses, and by [[8th millennium BC|7500 BC]] storage occurred in special rooms.<ref name="PNAS09"/> The first granaries measured 3 x 3 m on the outside and had suspended floors that protected the grain from rodents and insects and provided air circulation.<ref name="PNAS09"/>

These granaries are followed by those in [[Mehrgarh]] in the [[Indus Valley]] from 6000 BC. The [[ancient Egypt]]ians made a practice of preserving grain in years of plenty against years of scarcity. The climate of Egypt being very dry, grain could be stored in pits for a long time without discernible loss of quality. The silo pit, as it has been termed, has been a favorite way of storing grain from time immemorial in all oriental lands{{clarifyme|date=May 2016}}. In Turkey and Persia, [[usurer]]s used to buy up [[wheat]] or [[barley]] when comparatively cheap, and store it in hidden pits against seasons of dearth. In Malta a relatively large stock of wheat was preserved in some hundreds of pits (silos) cut in the rock. A single silo stored from 60 to 80 tons of wheat, which, with proper precautions, kept in good condition for four years or more.

==East Asia==
[[File:Han Dynasty Granary west of Dunhuang.jpg|thumb|300px|[[Han dynasty]] granary on [[Silk Road]] west of [[Dunhuang]]]]
Simple storage granaries raised up on four or more posts appeared in the [[Yangshao culture]] in China and after the onset of intensive agriculture in the Korean peninsula during the [[Mumun pottery period]] (c. 1000 B.C.) as well as in the Japanese archipelago during the Final [[Jōmon]]/Early [[Yayoi period]]s (c. 800 B.C.). In the archaeological vernacular of Northeast Asia, these features are lumped with those that may have also functioned as residences and together are called 'raised floor buildings'.

==Southeast Asia==
In [[Indonesian architecture|vernacular architecture]] of [[Indonesia|Indonesian archipelago]] granaries are made of wood and bamboo materials and most of them are built raised up on four or more posts to avoid rodents and insects. Examples of Indonesian granary is [[Sundanese people|Sundanese]] ''leuit'' and [[Minangkabau people|Minang]] ''[[rangkiang]]''.

==Great Britain==
In Great Britain small granaries were built on [[mushroom]] shaped stumps called [[staddle stones]]. They were built of timber frame construction and often had slate roofs. Larger ones were similar to [[linhay]]s, but with the upper floor enclosed. Access to the first floor was usually via stone staircase on the outside wall.<ref>http://www.southhams.gov.uk/index/business_index/ksp_development_and_planning/ksp-development_and_planning-conservation/sp-development_and_planning-barnguide.htm The Barn Guide by South Hams District Council</ref>

Towards the close of the 19th century, warehouses specially intended for holding grain began to multiply in Great Britain. There are climatic difficulties in the way of storing grain in Great Britain on a large scale, but these difficulties have been largely overcome.

==Modern==
[[File:Shelby County, Iowa. These granaries are located near Irwin Village, and much of the corn which is n . . . - NARA - 522350.jpg|thumb|Modern steel granaries in the United States]]
Modern grain farming operations often use manufactured steel granaries to store grain on-site until it can be trucked to major storage facilities in anticipation of shipping. The large ''mechanized'' facilities, particularly seen in Russia and North America are known as [[grain elevator]]s.
[[File:Port Perry grain mill and elevator circa 1930.jpg|thumb|The Port Perry mill and grain elevator, granary circa 1930. Originally built in 1873, the building remains a major landmark to this day as the oldest in Canada. The original line of the PW&PP Railway can be seen in the foreground.]]

== Moisture control ==
Grain must be kept away from moisture for as long as possible to preserve it in good condition and prevent [[molds|mold growth]]. Newly harvested grain brought into a granary tends to contain excess moisture, which encourages mold growth leading to fermentation and heating, both of which are undesirable and affect quality. Fermentation generally spoils grain and may cause chemical changes that create poisonous [[mycotoxins]].

One traditional remedy is to spread the grain in thin layers on a floor, where it is turned to aerate it thoroughly. Once the grain is sufficiently dry it can be transferred to a granary for storage. A modern variation on this, is to use a grain auger to move grain stored in one grainery to another.

In modern silos, grain is typically force-aerated ''in situ'' or circulated through external [[grain drying]] equipment.

==See also==
*[[Hórreo]]
*[[Raccard]]
*[[Storage silo]]
*[[Staddle stones]] Used to lift granaries off the ground to prevent access by vermin, etc.
*[[Corn crib]]
*[[Groote Schuur]], the stately South African home was originally a granary.
*[[Rice barn]]
*[[Treppenspeicher]]
*[[Ghorfa]]
*[[Parish granary]]
*[[Port Perry]]

== References ==
{{reflist}}

{{1911}}

{{wiktionary}}
{{commons category|Granaries}}

{{Prehistoric technology}}

[[Category:Granaries| ]]
[[Category:Containers]]
[[Category:Vernacular architecture]]
[[Category:Grain production]]

Coalplant

2017-08-09T21:24:53Z

81.147.69.112:

{{Use dmy dates|date=September 2016}}
[[File:Belchatow-elektrownia.jpg|thumb|upright=1.3|The 5,400 [[megawatt|MW]] [[Bełchatów Power Station]] in Poland – one of the [[List of coal power stations|world's largest]] coal-fired power stations.]]

A '''fossil fuel power station''' is a [[power station]] which burns [[fossil fuel]] such as [[coal]], [[natural gas]], or [[petroleum]] to produce [[electricity]]. Central station fossil fuel power plants are designed on a large scale for continuous operation. In many countries, such plants provide most of the [[electrical energy]] used. Fossil fuel power stations have machinery to convert the heat energy of [[combustion]] into [[mechanical energy]], which then operates an [[electrical generator]]. The [[Wiktionary:prime mover|prime mover]] may be a [[steam turbine]], a [[gas turbine]] or, in small plants, a reciprocating [[internal combustion]] engine. All plants use the energy extracted from expanding gas, either steam or combustion gases. Very few [[MHD generator]]s have been built which directly convert the energy of hot, moving water into electricity. MHD means [[Magnetohydrodynamics]], which is the study of the magnetic properties of electrically conducting fluids. Examples of such magnetofluids include plasmas, liquid metals, salt water and electrolytes.

By-products of thermal power plant operation must be considered in their design and operation. [[Waste heat]] energy, which remains due to the finite efficiency of the [[Carnot cycle|Carnot]], [[Rankine cycle|Rankine]], or [[Diesel cycle|Diesel]] power cycle, is released directly to the atmosphere or river/lake water, or indirectly to the atmosphere using a [[cooling tower]] with river or lake water used as a cooling medium. The [[flue gas]] from combustion of the fossil fuels is discharged to the air. This gas contains [[carbon dioxide]] and water vapor, as well as other substances such as [[nitrogen oxide]]s (NOx), [[sulfur oxide]]s (SOx), [[mercury (element)|mercury]], traces of other metals, and, for coal-fired plants, [[fly ash]]. Solid waste ash from coal-fired boilers must also be removed. Some coal ash can be recycled for building materials.<ref name="PCA Manual">{{cite web|title=PCA Manual|url=http://www.ce.memphis.edu/1101/notes/concrete/PCA_manual/Chap03.pdf|publisher=University of Memphis, Herff College of Civil Engineering|accessdate=8 January 2013|author=Charles Camp|author2=Department of Civil Engineering}}</ref>

Fossil fueled power stations are major emitters of [[carbon dioxide]] (CO2), a [[greenhouse gas]] which according to a [[Scientific opinion on climate change|consensus opinion of scientific organisations]] is a contributor to [[global warming]]. The results of a recent study<ref>N. Heidari & J. M. Pearce. A Review of Greenhouse Gas Emission Liabilities as the Value of Renewable Energy for Mitigating Lawsuits for Climate Change Related Damages. ''Renewable and Sustainable Energy Reviews'' '''55'''C (2016) pp. 899-908. DOI:10.1016/j.rser.2015.11.025 [https://www.academia.edu/19418589/A_Review_of_Greenhouse_Gas_Emission_Liabilities_as_the_Value_of_Renewable_Energy_for_Mitigating_Lawsuits_for_Climate_Change_Related_Damages open access]</ref> show that the [[net income]] available to shareholders of large companies could see a significant reduction from the [[greenhouse gas emissions]] liability related to only natural disasters in the U.S. from a single coal-fired power plant. However, as of 2015, no such cases have awarded damages in the U.S. Per unit of electric energy, [[brown coal]] emits nearly two times as much CO2 as natural gas, and black coal emits somewhat less than brown. [[Carbon capture and storage]] of emissions is not currently available.{{Citation needed|reason=Clarification and reliable source needed for the whole sentence; not commercially available? not actively in widespread use? not possible?|date=July 2017}}

==Basic concepts==
In a fossil fuel power plant the chemical energy stored in fossil fuels such as [[coal]], [[fuel oil]], [[natural gas]] or [[oil shale]] and [[oxygen]] of the [[air]] is converted successively into [[thermal energy]], [[mechanical energy]] and, finally, [[electrical energy]]. Each fossil fuel power plant is a complex, custom-designed system. Construction costs, {{As of|2004|lc=on}}, run to [[United States dollar|US$]]1,300 per [[kilowatt]], or $650 million for a 500 [[MWe]] unit{{Citation needed|date=March 2009}}. Multiple generating units may be built at a single site for more efficient use of [[land use|land]], [[natural resource]]s and [[labor (economics)|labor]]. Most [[thermal power station]]s in the world use fossil fuel, outnumbering [[nuclear power|nuclear]], [[geothermal power|geothermal]], [[biomass]], or [[solar energy|solar thermal]] plants.

===Heat into mechanical energy===
The [[second law of thermodynamics]] states that any [[Thermodynamic cycle|closed-loop cycle]] can only convert a fraction of the heat produced during combustion into [[mechanical work]]. The rest of the heat, called [[waste heat]], must be released into a cooler environment during the return portion of the cycle. The fraction of heat released into a cooler medium must be equal or larger than the ratio of [[absolute temperature]]s of the cooling system (environment) and the heat source (combustion furnace). Raising the furnace temperature improves the efficiency but complicates the design, primarily by the selection of alloys used for construction, making the furnace more expensive. The waste heat cannot be converted into mechanical energy without an even cooler cooling system. However, it may be used in [[cogeneration]] plants to heat buildings, produce hot water, or to heat materials on an industrial scale, such as in some [[oil refinery|oil refineries]], plants, and [[chemical synthesis]] plants.

Typical thermal efficiency for utility-scale electrical generators is around 33% for coal and oil-fired plants, and 56 – 60% (LHV) for [[combined-cycle]] gas-fired plants. Plants designed to achieve peak efficiency while operating at capacity will be less efficient when operating off-design (i.e. temperatures too low.)<ref name="ELECTRIC GENERATION
EFFICIENCY Page 5">{{cite web|url=http://www.npc.org/study_topic_papers/4-dtg-electricefficiency.pdf|title=ELECTRIC GENERATION EFFICIENCY: Working Document of the NPC Global Oil & Gas Study|publisher=Highbeam Research|accessdate=18 July 2007}}</ref>

Practical fossil fuel stations operating as heat engines cannot exceed the [[Carnot cycle]] limit for conversion of heat energy into useful work. [[Fuel cell]]s do not have the same thermodynamic limits as they are not heat engines.

'''Temperature of Hot Steam'''.
Using the reported efficiencies and the efficiency of an ideal [[Carnot engine]] one can estimate the engine temperature. This estimate is the minimum heat water/steam temperature as we neglect other losses. For example, the effective temperature of the cooling water can be significantly higher.
Assume the cold temperature <math> T_c </math> is 10 °C, or 280 K than <math> T_h </math> equals:
: <math> \eta \,=\, 1 - \frac{T_c}{T_h} </math>
: <math> T_h \,=\, \frac{T_c}{1 - \eta} </math>
: <math> T_h \,=\, \frac{280}{1 - 0.33} </math>
: <math> T_h \,=\, 418\, \mathrm{K} = 145^o \mathrm{C} </math>

This temperature is presumably much lower than the actual steam temperature due to several losses.

==Coal==
[[File:Coal fired power plant diagram.svg|thumb|upright=1.3|Diagram of a typical steam-cycle coal power plant (proceeding from left to right)]]
{{main|Thermal power station}}

Coal is the most abundant [[fossil fuel]] on the planet, and widely used as the source of energy in [[thermal power station]]s. It is a relatively cheap fuel, with some of the largest deposits in regions that are stable politically, such as [[China]], [[India]] and the [[United States]]. This contrasts with [[natural gas]], the largest deposits of which are located in Russia, Iran, Qatar, Turkmenistan and the US. Solid coal cannot directly replace natural gas or petroleum in most applications, petroleum is mostly used for [[transportation]] and the natural gas not used for [[electricity generation]] is used for [[space heating|space]], [[water heating|water]] and industrial heating. Coal can be converted to gas or liquid fuel, but the efficiencies and economics of such processes can make them unfeasible.{{Citation needed|date=January 2013}} Vehicles or heaters may require modification to use coal-derived fuels. Coal is an impure fuel and produces more [[greenhouse gas]] and [[pollution]] than an equivalent amount of petroleum or natural gas. For instance, the operation of a 1000-MWe coal-fired power plant results in a nuclear radiation dose of 490 person-rem/year, compared to 136 person-rem/year, for an equivalent nuclear power plant including uranium mining, reactor operation and waste disposal.<ref>https://www.ornl.gov/sites/default/files/ORNL%20Review%20v26n3-4%201993.pdf pg28</ref>

{{As of|2009}} the largest coal-fired power station is [[Taichung Power Plant]] in [[Taiwan]]. The world's most energy-efficient coal-fired power plant is the [[Avedøre Power Station]] in [[Denmark]].<ref>[http://www.dongenergy.com/en/business%20activities/generation/electricity%20generation/primary%20power%20stations/pages/avedore%20power%20station.aspx Avedøre Power Station] {{webarchive |url=https://web.archive.org/web/20120225021554/http://www.dongenergy.com/en/business%20activities/generation/electricity%20generation/primary%20power%20stations/pages/avedore%20power%20station.aspx |date=25 February 2012 }} from the web page of [[DONG Energy]]</ref>

===Fuel transport and delivery===
[[File:Grand Junction Trip 92007 098.JPG|thumb|Coal-fired power plants provide about 39 percent of consumed electricity in the United States, as of March 2016.<ref>Siera Magazine</ref> This is the [[Carbon Power Plant|Castle Gate Plant]] near [[Helper, Utah]].]]

Coal is delivered by highway [[truck]], [[railroad|rail]], [[barge]], [[Collier (ship type)|collier]] ship or [[coal slurry pipeline]]. Some plants are even built near coal mines and coal is delivered by conveyors. A large coal [[train]] called a "unit train" may be two kilometers (over a mile) long, containing 130-140 cars with 100 [[short ton]]s of coal in each one, for a total load of over 15,000 tons. A large plant under full load requires at least one coal delivery this size every day. Plants may get as many as three to five trains a day, especially in "peak season" during the hottest summer or coldest winter months (depending on local climate) when power consumption is high. A large thermal power plant such as the now decommissioned [[Nanticoke Generating Station|Nanticoke]], Ontario stores several million metric tons of coal for winter use when the lakes are frozen.

Modern unloaders use rotary dump devices, which eliminate problems with coal freezing in bottom dump cars. The unloader includes a train positioner arm that pulls the entire train to position each car over a coal hopper. The dumper clamps an individual car against a platform that swivels the car upside down to dump the coal. Swiveling couplers enable the entire operation to occur while the cars are still coupled together. Unloading a unit train takes about three hours.

Shorter trains may use railcars with an "air-dump", which relies on air pressure from the engine plus a "hot shoe" on each car. This "hot shoe" when it comes into contact with a "hot rail" at the unloading trestle, shoots an electric charge through the air dump apparatus and causes the doors on the bottom of the car to open, dumping the coal through the opening in the trestle. Unloading one of these trains takes anywhere from an hour to an hour and a half. Older unloaders may still use manually operated bottom-dump rail cars and a "shaker" attached to dump the coal. Generating stations adjacent to a mine may receive coal by [[conveyor belt]] or massive [[diesel-electric]]-drive [[haul truck|trucks]].

A collier (cargo ship carrying coal) may hold 40,000 long tons of coal and takes several days to unload. Some colliers carry their own conveying equipment to unload their own bunkers; others depend on equipment at the plant. For transporting coal in calmer waters, such as rivers and lakes, flat-bottomed [[barge]]s are often used. Barges are usually unpowered and must be moved by [[tugboat]]s or [[towboat]]s.

For start up or auxiliary purposes, the plant may use fuel oil as well. Fuel oil can be delivered to plants by [[Pipeline transport|pipeline]], [[Tanker (ship)|tanker]], [[tank car]] or truck. Oil is stored in vertical cylindrical steel tanks with capacities as high as {{convert|90000|oilbbl}}' worth. The [[viscosity|heavier]] no. 5 "bunker" and no. 6 fuels are typically steam-heated before pumping in cold climates.

===Fuel processing===
Coal is prepared for use by crushing the rough coal to pieces less than {{convert|2|in|cm|sigfig=1}} in size. The coal is then transported from the storage yard to in-plant storage silos by [[conveyor belt]]s at rates up to 4,000 short tons per hour.

In plants that burn pulverized coal, silos feed coal to [[pulverizer]]s (coal mills) that take the larger {{convert|2|in|mm|adj=on}} pieces, grind them to the consistency of [[talcum powder]], sort them, and mix them with primary combustion air which transports the coal to the boiler furnace and preheats the coal in order to drive off excess moisture content. A 500 MWe plant may have six such pulverizers, five of which can supply coal to the furnace at 250 tons per hour under full load.

In plants that do not burn pulverized coal, the larger {{convert|2|in|mm|adj=on}} pieces may be directly fed into the silos which then feed either mechanical distributors that drop the coal on a traveling grate or the [[Cyclone furnace|cyclone]] burners, a specific kind of combustor that can efficiently burn larger pieces of fuel.

==Combined heat and power==
[[Combined heat and power]] (CHP), also known as [[cogeneration]], is the use of a [[thermal power station]] to provide both electric power and heat (the latter being used i.e. for [[district heating]] purposes). This technology is widely practiced in for example Denmark, as well as other Scandinavian countries and parts of Germany. Calculations show that Combined Heat and Power District Heating (CHPDH) is the cheapest method in reducing (but not eliminating) carbon emissions, if conventional fossil fuels remain to be burned.<ref>[http://www.claverton-energy.com/carbon-footprints-of-various-sources-of-heat-chpdh-comes-out-lowest.html Claverton-energy.co.uk]</ref>

==Gas turbine plants==
[[File:GE H series Gas Turbine.jpg|thumb|480 [[megawatt]] GE H series power generation gas turbine]]
[[File:Currant Creek Power Plant.jpg|thumb|Currant Creek Power Plant near [[Mona, Utah]] is a [[natural gas]] fired electrical plant.]]

One type of fossil fuel power plant uses a [[gas turbine]] in conjunction with a [[heat recovery steam generator]] (HRSG). It is referred to as a [[combined cycle]] power plant because it combines the [[Brayton cycle]] of the gas turbine with the [[Rankine cycle]] of the HRSG. The thermal efficiency of these plants has reached a record [[thermal efficiency|heat rate]] of 5690 Btu/(kW·h), or just under 60%, at a facility in Baglan Bay, Wales.<ref>[http://www.ge-energy.com/prod_serv/products/gas_turbines_cc/en/h_system/index.htm GE Power’s H Series Turbine] {{webarchive |url=https://web.archive.org/web/20071111004450/http://www.ge-energy.com/prod_serv/products/gas_turbines_cc/en/h_system/index.htm |date=11 November 2007 }}</ref>

The turbines are fueled either with natural gas, [[syngas]] or fuel oil. While more efficient and faster to construct (a 1,000 MW plant may be completed in as little as 18 months from start of construction), the economics of such plants is heavily influenced by the volatile cost of fuel, normally natural gas. The combined cycle plants are designed in a variety of configurations composed of the number of gas turbines followed by the steam turbine. For example, a 3-1 combined cycle facility has three gas turbines tied to one steam turbine. The configurations range from (1-1), (2-1), (3-1), (4-1), (5-1), to (6-1){{Citation needed|date=January 2013}}

Simple-cycle or open cycle gas turbine plants, without a steam cycle, are sometimes installed as emergency or [[peaking power plant|peaking]] capacity; their thermal efficiency is much lower. The high running cost per hour is offset by the low capital cost and the intention to run such units only a few hundred hours per year. Other gas turbine plants are installed in stages, with an open cycle gas turbine the first stage and additional turbines or conversion to a closed cycle part of future project plans.

===Dash for gas===
In the 1990s was the [[dash for gas]] where 30 gas-fired power stations were built in Britain due to plentiful gas supplies from [[North Sea Gas|North Sea oil wells]]. According to the 2012 forecast by the U.S. Energy Information Administration, 27 gigawatts of capacity from coal-fired generators is to be retired from 175 US coal-fired power plants before 2016.<ref>{{Cite news|last=Gerhardt|first=Tina|date=1 November 2012|title=Record Number of Coal Power Plants Retire|url=http://www.emagazine.com/magazine/by-the-numbers-record-number-of-coal-power-plants-retire|archive-url=https://web.archive.org/web/20121101010101/http://www.emagazine.com/magazine/by%2Dthe%2Dnumbers%2Drecord%2Dnumber%2Dof%2Dcoal%2Dpower%2Dplants%2Dretire|work=[[E-Magazine]]|dead-url=yes|archivedate=1 November 2012}}</ref> Natural gas showed a corresponding jump, increasing by a third over 2011.<ref name="epm_312">Electric Power Monthly, March 2011 (released May 2012), U.S. Energy Information Administration</ref> Some [[Thermal power station|coal power plants]] such as the 1200 MW [[Hearn Generating Station]] have stopped burning coal by switching the plant to natural gas. Coal's share of electricity generation dropped to just over 36%.<ref name="epm_312" /> Natural gas accounted for 81% of new power generation in the US between 2000 and 2010.<ref>[http://www.eia.gov/todayinenergy/detail.cfm?id=2070 Most electric generating capacity additions in the last decade were natural gas-fired - Today in Energy - U.S. Energy Information Administration (EIA)]</ref> Coal-fired generation puts out about twice the amount of carbon dioxide - around 2,000 pounds for every megawatt hour generated - than electricity generated by burning natural gas at 1,100 pounds of [[greenhouse gas]] per megawatt hour. As the fuel mix in the United States has changed to reduce coal and increase natural gas generation, carbon dioxide emissions have unexpectedly fallen. Carbon dioxide measured in the first quarter of 2012 was the lowest recorded of any year since 1992.<ref>cite web |first=Rachel |last=Nuwer |title=A 20-Year Low in U.S. Carbon Emissions |url=http://green.blogs.nytimes.com/2012/08/17/a-20-year-low-in-u-s-carbon-emissions/ |date=August 17, 2012</ref> The [[list of natural gas power stations]] has over 100 power stations that generate between 100MW and 5,600MW of electricity. Natural gas plants are increasing in popularity and in 2014 generated 22% of the worlds total electricity.<ref>[http://www.iea.org/publications/freepublications/publication/KeyWorld2014.pdf pg24 Free publications]</ref>

==Reciprocating engines==
[[Diesel engine]] generator sets are often used for prime power in communities not connected to a widespread power grid. Emergency (standby) power systems may use reciprocating internal combustion engines operated by fuel oil or natural gas. Standby generators may serve as emergency power for a factory or data center, or may also be operated in parallel with the local utility system to reduce peak power demand charge from the utility. Diesel engines can produce strong torque at relatively low rotational speeds, which is generally desirable when driving an [[alternator]], but diesel fuel in long-term storage can be subject to problems resulting from water accumulation and [[chemical decomposition]]. Rarely used generator sets may correspondingly be installed as natural gas or LPG to minimize the fuel system maintenance requirements.

Spark-ignition internal combustion engines operating on gasoline (petrol), [[propane]], or [[Liquefied petroleum gas|LPG]] are commonly used as portable temporary power sources for construction work, emergency power, or recreational uses.

Reciprocating external combustion engines such as the [[Stirling engine]] can be run on a variety of fossil fuels, as well as renewable fuels or industrial waste heat. Installations of Stirling engines for power production are relatively uncommon.

==Environmental impacts==
[[File:Mohave Generating Station 1.jpg|thumb|The [[Mohave Power Station]], a 1,580 [[Megawatt|MW]] coal power station near [[Laughlin, Nevada]], out of service since 2005 due to environmental
restrictions<ref>[http://www.sce.com/PowerandEnvironment/PowerGeneration/MohaveGenerationStation/ SEC Mohave Generation Station] {{webarchive |url=https://web.archive.org/web/20080914140440/http://www.sce.com/PowerandEnvironment/PowerGeneration/MohaveGenerationStation/ |date=14 September 2008 }} Retrieved 24-07-2008</ref>]]
The [[World energy resources and consumption|world's power demands]] are expected to rise 60% by 2030.<ref name=WorldOutlook2004>
{{Citation
|title=World Outlook 2004
|publisher=[[International Energy Agency|IEA]]
|date=October 26, 2004
|url=http://www.iea.org/textbase/nppdf/free/2004/weo2004.pdf
|accessdate=June 13, 2006
|page=31
|location=Paris
|isbn=92-64-10817-3
|deadurl=yes
|archiveurl=https://web.archive.org/web/20060622104453/http://iea.org:80/textbase/nppdf/free/2004/weo2004.pdf
|archivedate=22 June 2006
|df=dmy
}}
</ref>
World organizations and international agencies, like the IEA, are concerned about the [[Environmental impact of fossil fuels|environmental impact of burning fossil fuels]], and coal in particular. The combustion of coal contributes the most to [[acid rain]] and [[air pollution]], and has been connected with [[global warming]]. Due to the chemical composition of coal there are difficulties in removing impurities from the solid fuel prior to its combustion. Modern day coal power plants pollute less than older designs due to new "[[scrubber]]" technologies that filter the exhaust air in smoke stacks; however emission levels of various pollutants are still on average several times greater than natural gas power plants. In these modern designs, pollution from coal-fired power plants comes from the emission of gases such as carbon dioxide, [[nitrogen oxides]], and [[sulfur dioxide]] into the air.

Acid rain is caused by the emission of [[nitrogen oxides]] and [[sulfur dioxide]]. These gases may be only mildly acidic themselves, yet when they react with the atmosphere, they create acidic compounds such as [[sulfurous acid]], [[nitric acid]] and [[sulfuric acid]] which fall as rain, hence the term acid rain. In Europe and the U.S.A., stricter emission laws and decline in heavy industries have reduced the environmental hazards associated with this problem, leading to lower emissions after their peak in 1960s.

{| class="wikitable sortable"
|- class="hintergrundfarbe6"
|+Carbon dioxide and other air pollution of the 9 greatest brown coal power plants in Germany ([[Pollutant release and transfer register|PRTR 2010]])<ref name=PRTR>[http://www.prtr.bund.de/ PRTR - Europäisches Emissionsregister]</ref>
!Power plant
![[carbon dioxide|CO2]] (Tons)
![[nitrogen dioxide|NOx/NO2]] (Tons)
![[sulfur dioxide|SOx/SO2]] (Tons)
!Fine Dust (Tons)
![[mercury (element)|Hg]] (kg)
![[Cadmium|Cd]] (kg)
![[Nickel|Ni]] (kg)
![[Blei|Pb]] (kg)
![[Arsen|As]] (kg)
![[Chromium|Cr]] (kg)
|-
|Power plant Niederaußem|Niederaußem
|style="text-align:right"|28,100,000
|style="text-align:right"|17,900
|style="text-align:right"|6,870
|style="text-align:right"|386
|style="text-align:right"|499
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|49.9
|style="text-align:right"|<100
|-
|Power plant Jänschwalde|Jänschwalde*
|style="text-align:right"|23,800,000
|style="text-align:right"|18,700
|style="text-align:right"|21,400
|style="text-align:right"|573
|style="text-align:right"|592
|style="text-align:right"|<10
|style="text-align:right"|308
|style="text-align:right"|<200
|style="text-align:right"|129
|style="text-align:right"|<100
|-
|Power plant Weisweiler|Weisweiler
|style="text-align:right"|19,900,000
|style="text-align:right"|12,700
|style="text-align:right"|3,060
|style="text-align:right"|456
|style="text-align:right"|271
|style="text-align:right"|<10
|style="text-align:right"|103
|style="text-align:right"|<200
|style="text-align:right"|67
|style="text-align:right"|<100
|-
|Power plant Neurath|Neurath
|style="text-align:right"|16,900,000
|style="text-align:right"|11,700
|style="text-align:right"|3,190
|style="text-align:right"|251
|style="text-align:right"|181
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|42.2
|style="text-align:right"|<100
|-
|Power plant Boxberg|Boxberg
|style="text-align:right"|15,100,000
|style="text-align:right"|10,700
|style="text-align:right"|7,810
|style="text-align:right"|167
|style="text-align:right"|226
|style="text-align:right"|<10
|style="text-align:right"|152
|style="text-align:right"|236
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Frimmersdorf|Frimmersdorf
|style="text-align:right"|14,400,000
|style="text-align:right"|9,070
|style="text-align:right"|5,620
|style="text-align:right"|257
|style="text-align:right"|153
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|35.7
|style="text-align:right"|<100
|-
|Power plant Lippendorf|Lippendorf**
|style="text-align:right"|12,500,000
|style="text-align:right"|8,570
|style="text-align:right"|13,800
|style="text-align:right"|108
|style="text-align:right"|1,160
|style="text-align:right"|68
|style="text-align:right"|1,960
|style="text-align:right"|789
|style="text-align:right"|21
|style="text-align:right"|466
|-
|Power plant Schwarze Pumpe|Schwarze Pumpe
|style="text-align:right"|11,200,000
|style="text-align:right"|4,610
|style="text-align:right"|7,060
|style="text-align:right"|<100
|style="text-align:right"|243
|style="text-align:right"|62.9
|style="text-align:right"|<50
|style="text-align:right"|369
|style="text-align:right"|35.8
|style="text-align:right"|224
|-
|Power plant Schkopau|Schkopau
|style="text-align:right"|5,120,000
|style="text-align:right"|3,320
|style="text-align:right"|4,770
|style="text-align:right"|74.6
|style="text-align:right"|227
|style="text-align:right"|129
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|- class="hintergrundfarbe5"
|Sum without "<"
|style="text-align:right"|147,020,000
|style="text-align:right"|97,270
|style="text-align:right"|73,580
|style="text-align:right"|2,273
|style="text-align:right"|3,552
|style="text-align:right"|260
|style="text-align:right"|2,523
|style="text-align:right"|1,394
|style="text-align:right"|381
|style="text-align:right"|690
|-
|[[Deutschland|DE]] All together 2010<ref name="Trendtabelle">[http://www.umweltbundesamt.de/emissionen/publikationen.htm Emissionsentwicklung 1990 - 2011, klassische Luftschadstoffe, Schwermetalle] Nationale Trendtabellen für die deutsche Berichterstattung atmosphärischer Emissionen seit 1990, Umweltbundesamt (Excel-Tabelle), 2013</ref>
|style="text-align:right"|834,511,385
|style="text-align:right"|1,328,717
|style="text-align:right"|444,035
|style="text-align:right"|211,284
|style="text-align:right"|9,412
|style="text-align:right"|4,723
|style="text-align:right"|105,802
|style="text-align:right"|193,968
|style="text-align:right"|6,120
|style="text-align:right"|55,060
|-
|Share of all together
|style="text-align:right"|18 %
|style="text-align:right"|7.3 %
|style="text-align:right"|17 %
|style="text-align:right"|1.1 %
|style="text-align:right"|38 %
|style="text-align:right"|5.5 %
|style="text-align:right"|2.4 %
|style="text-align:right"|0.7 %
|style="text-align:right"|6.2 %
|style="text-align:right"|1.3 %
|-
|colspan="11"|* with [[Fuel surrogate]] and [[Waste-to-energy]] ** with [[Biosolids#Biosolids|biosolids]]-[[Waste-to-energy]]
|}
{| class="wikitable sortable"
|- class="hintergrundfarbe6"
|+Carbon dioxide and other air pollution of the 14 greatest stone coal power plants in Germany
[[Pollutant release and transfer register|PRTR 2010]]<ref name=PRTR />
!Power plant
![[carbon dioxide|CO2]] (Tons)
![[nitrogen dioxide|NOx/NO2]] (Tons)
![[sulfur dioxide|SOx/SO2]] (Tons)
!Fine dust (Tons)
![[mercury (element)|Hg]] (kg)
![[Cadmium|Cd]] (kg)
![[Nickel|Ni]] (kg)
![[Blei|Pb]] (kg)
![[Arsen|As]] (kg)
![[Chromium|Cr]] (kg)
|-
|Power plant Scholven|Scholven
|style="text-align:right"|9,390,000
|style="text-align:right"|7,090
|style="text-align:right"|4,330
|style="text-align:right"|244
|style="text-align:right"|135
|style="text-align:right"|31
|style="text-align:right"|86
|style="text-align:right"|<200
|style="text-align:right"|51
|style="text-align:right"|<100
|-
|Power plant Mannheim|Mannheim
|style="text-align:right"|6,510,000
|style="text-align:right"|3,550
|style="text-align:right"|1,490
|style="text-align:right"|148
|style="text-align:right"|146
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|68
|style="text-align:right"|<100
|-
|Power plant Voerde|Voerde
|style="text-align:right"|6,240,000
|style="text-align:right"|4,700
|style="text-align:right"|2,840
|style="text-align:right"|<100
|style="text-align:right"|38.3
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Staudinger Großkrotzenburg|Staudinger*
|style="text-align:right"|4,480,000
|style="text-align:right"|2,770
|style="text-align:right"|665
|style="text-align:right"|69.9
|style="text-align:right"|45.6
|style="text-align:right"|19.1
|style="text-align:right"|131
|style="text-align:right"|<200
|style="text-align:right"|113
|style="text-align:right"|192
|-
|Power plant Heyden|Heyden
|style="text-align:right"|3,870,000
|style="text-align:right"|2,920
|style="text-align:right"|1,380
|style="text-align:right"|86.7
|style="text-align:right"|28.4
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Heilbronn|Heilbronn
|style="text-align:right"|3,240,000
|style="text-align:right"|2,160
|style="text-align:right"|1,660
|style="text-align:right"|<100
|style="text-align:right"|34
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Gersteinwerk|Werne*
|style="text-align:right"|3,140,000
|style="text-align:right"|1,900
|style="text-align:right"|1,170
|style="text-align:right"|<100
|style="text-align:right"|11.5
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Wilhelmshaven (E.ON)|Wilhelmshaven
|style="text-align:right"|3,100,000
|style="text-align:right"|2,040
|style="text-align:right"|1,390
|style="text-align:right"|136
|style="text-align:right"|29.9
|style="text-align:right"|11.7
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Bergkamen|Bergkamen
|style="text-align:right"|3,020,000
|style="text-align:right"|2,100
|style="text-align:right"|2,040
|style="text-align:right"|<100
|style="text-align:right"|18.1
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Herne|Herne
|style="text-align:right"|2,480,000
|style="text-align:right"|1,790
|style="text-align:right"|1,340
|style="text-align:right"|<100
|style="text-align:right"|30.3
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Altbach/Deizisau|Altbach**
|style="text-align:right"|2,220,000
|style="text-align:right"|1,350
|style="text-align:right"|906
|style="text-align:right"|<100
|style="text-align:right"|30
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Rheinhafen-Steam-Power plant Karlsruhe|Karlsruhe*
|style="text-align:right"|2,170,000
|style="text-align:right"|1,140
|style="text-align:right"|1,080
|style="text-align:right"|<100
|style="text-align:right"|19
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Veltheim|Veltheim**
|style="text-align:right"|1,740,000
|style="text-align:right"|1,290
|style="text-align:right"|400
|style="text-align:right"|52.6
|style="text-align:right"|10.1
|style="text-align:right"|22.4
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|156
|style="text-align:right"|<100
|-
|Power plant Bexbach|Bexbach
|style="text-align:right"|1,300,000
|style="text-align:right"|910
|style="text-align:right"|746
|style="text-align:right"|<100
|style="text-align:right"|<10
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|- class="hintergrundfarbe5"
|Sum without "<"
|style="text-align:right"|52,900,000
|style="text-align:right"|35,710
|style="text-align:right"|21,437
|style="text-align:right"|737
|style="text-align:right"|576
|style="text-align:right"|84
|style="text-align:right"|217
|style="text-align:right"| -
|style="text-align:right"|388
|style="text-align:right"|192
|-
|[[Deutschland|DE]] All together 2010<ref name="Trendtabelle" />
|style="text-align:right"|834,511,385
|style="text-align:right"|1,328,717
|style="text-align:right"|444,035
|style="text-align:right"|211,284
|style="text-align:right"|9,412
|style="text-align:right"|4,723
|style="text-align:right"|105,802
|style="text-align:right"|193,968
|style="text-align:right"|6,120
|style="text-align:right"|55,060
|-
|Share of all together
|style="text-align:right"|6.3 %
|style="text-align:right"|2.7 %
|style="text-align:right"|4.8 %
|style="text-align:right"|0.3 %
|style="text-align:right"|6.1 %
|style="text-align:right"|1.8 %
|style="text-align:right"|0.2 %
|style="text-align:right"| -
|style="text-align:right"|6.3 %
|style="text-align:right"|0.3 %
|-
|colspan="11"|* with earth gas share, ** with oil- and earth gas share
|}

In 2008, the [[European Environment Agency]] (EEA) documented fuel-dependent emission factors based on actual emissions from power plants in the [[European Union]].<ref name=EEA_AirPollution>
{{Citation
| title = Air pollution from electricity-generating large combustion plants
| publisher = European Environment Agency (EEA)
| year = 2008
| url = http://www.eea.europa.eu/publications/technical_report_2008_4/at_download/file
| format=PDF
| accessdate =
| pages =
| location = Copenhagen
| isbn = 978-92-9167-355-1 }}
</ref>
{| class="wikitable"
|-
! Pollutant !! Hard coal !! Brown coal !! Fuel oil !! Other oil !! Gas
|-
| CO2 (g/GJ) || 94,600 || 101,000 || 77,400 || 74,100 || 56,100
|-
| SO2 (g/GJ) || 765 || 1,361 || 1,350 || 228 || 0.68
|-
| NOx (g/GJ) || 292 || 183 || 195 || 129 || 93.3
|-
| CO (g/GJ) || 89.1 || 89.1 || 15.7 || 15.7 || 14.5
|-
| Non methane organic compounds (g/GJ) || 4.92 || 7.78 || 3.70 || 3.24 || 1.58
|-
| Particulate matter (g/GJ) || 1,203 || 3,254 || 16 || 1.91 || 0.1
|-
| Flue gas volume total (m3/GJ) || 360 || 444 || 279 || 276 || 272
|}

===Carbon dioxide===
{{Main|Carbon dioxide}}
[[File:Taichung Thermal Power Plant.JPG|thumb|[[Taichung Power Plant|Taichung coal-fired power plant]] in [[Taiwan]], the world's largest carbon dioxide emitter<ref>[http://thephoenixsun.com/archives/6548 The Phoenix Sun | Dirty numbers | The 200 Most Polluting Power Plants in the World]</ref>]]

Electricity generation using carbon based fuels is responsible for a large fraction of carbon dioxide (CO2) emissions worldwide and for 34% of U.S. man-made carbon dioxide emissions in 2010. In the U.S. 70% of electricity generation is produced from combustion of fossil fuels.<ref>{{cite web
|url= http://www.epa.gov/climatechange/ghgemissions/sources.html
|title=Sources Climate Change
|work= US EPA
|year=2012
|accessdate=August 26, 2012}}</ref>

Of the fossil fuels, coal is much more carbon intensive than oil or natural gas, resulting in greater volumes of [[carbon dioxide]] emissions per unit of electricity generated. In 2010, coal contributed about 81% of CO2 emissions from generation and contributed about 45% of the electricity generated in the United States.<ref>{{cite web
|url= http://www.epa.gov/climatechange/ghgemissions/sources/electricity.html
|title=Electricity Sector Emissions Climate Change
|work= US EPA
|year=2012
|accessdate=August 26, 2012}}</ref> In 2000, the carbon intensity of U.S. coal thermal combustion was 2249 lbs/MWh (1,029 kg/MWh)<ref>[http://www.epa.gov/cleanrgy/energy-and-you/affect/coal.html ''US EPA Clean Energy—Coal'']</ref> while the carbon intensity of U.S. oil thermal generation was 1672 lb/MWh (758 kg/MWh or 211 kg/[[gigajoule|GJ]])<ref>[http://www.epa.gov/cleanrgy/energy-and-you/affect/oil.html ''US EPA Clean Energy—Oil]</ref> and the carbon intensity of U.S. natural gas thermal production was 1135 lb/MWh (515 kg/MWh or 143 kg/GJ).<ref>[http://www.epa.gov/cleanrgy/energy-and-you/affect/natural-gas.html ''US EPA Clean Energy—Gas'']</ref>

The Intergovernmental Panel on Climate Change (see [[IPCC]]) states that carbon dioxide is a greenhouse gas and that increased quantities within the atmosphere will "very likely" lead to higher average temperatures on a global scale ([[global warming]]); concerns regarding the potential for such warming to change the global climate prompted IPCC recommendations calling for large cuts to CO2 emissions worldwide.<ref name="ipcc summary">{{cite web|url=http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf|title=Summary for policymakers|last=Solomon, S.|year=2007|work=A report of Working Group I of the Intergovernmental Panel on Climate Change|publisher=IPCC|accessdate=24 March 2010|display-authors=etal}}</ref>

Emissions may be reduced through more efficient and higher combustion temperature and through more efficient production of electricity within the cycle. [[Carbon capture and storage]] (CCS) of emissions from coal-fired power stations is another alternative but the technology is still being developed and will increase the cost of fossil fuel-based production of electricity. CCS may not be economically viable, unless the price of emitting CO2 to the atmosphere rises.

===Particulate matter===
Another problem related to coal combustion is the emission of [[Atmospheric particulate matter|particulates]] that have a serious impact on public health. Power plants remove particulate from the flue gas with the use of a [[Dust collector#Fabric filters|bag house]] or [[electrostatic precipitator]]. Several newer plants that burn coal use a different process, [[Combined cycle#Integrated Gasification Combined Cycle (IGCC)|Integrated Gasification Combined Cycle]] in which [[synthesis gas]] is made out of a reaction between coal and water. The synthesis gas is processed to remove most pollutants and then used initially to power gas turbines. Then the hot exhaust gases from the gas turbines are used to generate steam to power a steam turbine. The pollution levels of such plants are drastically lower than those of "classic" coal power plants.<ref>{{Citation
| title = Energy research at DOE: was it worth it? Energy efficiency and fossil energy research 1978 to 2000
| place =
| publisher = National Academies Press
| year = 2001
| volume =
| edition =
| page = 174
| url =
| doi =
| id =
| isbn = 0-309-07448-7
| author = Committee on Benefits of DOE R&D on Energy Efficiency and Fossil Energy, [[United States National Research Council|US NRC]]}}
</ref>

Particulate matter from coal-fired plants can be harmful and have negative health impacts. Studies have shown that exposure to particulate matter is related to an increase of respiratory and cardiac mortality.<ref name="Nel, A. 2005">Nel, A. (2005, May 6). Air Pollution-Related Illness: Effects of Particles. Science, 308(5723), 804-806.</ref> Particulate matter can irritate small airways in the lungs, which can lead to increased problems with asthma, chronic bronchitis, airway obstruction, and gas exchange.<ref name="Nel, A. 2005"/>

There are different types of particulate matter, depending on the chemical composition and size. The dominant form of particulate matter from coal-fired plants is [[Fly ash|coal fly ash]], but secondary sulfate and nitrate also comprise a major portion of the particulate matter from coal-fired plants.<ref name="Grahame, T. 2007">Grahame, T., & Schlesinger, R. (2007, April 15). Health Effects of Airborne Particulate Matter: Do We Know Enough to Consider Regulating Specific Particle Types or Sources?. Inhalation Toxicology, 19(6–7), 457–481.</ref> Coal fly ash is what remains after the coal has been combusted, so it consists of the incombustible materials that are found in the coal.<ref name="Schobert, H. H. 2002">Schobert, H. H. (2002). ''Energy and Society.'' New York: Taylor & Francis, 241–255.</ref>

The size and chemical composition of these particles affects the impacts on human health.<ref name="Nel, A. 2005"/><ref name="Grahame, T. 2007"/> Currently coarse (diameter greater than 2.5 μm) and fine (diameter between 0.1 μm and 2.5 μm) particles are regulated, but ultrafine particles (diameter less than 0.1 μm) are currently unregulated, yet they pose many dangers.<ref name="Nel, A. 2005"/> Unfortunately much is still unknown as to which kinds of particulate matter pose the most harm, which makes it difficult to come up with adequate legislation for regulating particulate matter.<ref name="Grahame, T. 2007"/>

There are several methods of helping to reduce the particulate matter emissions from coal-fired plants. Roughly 80% of the ash falls into an ash hopper, but the rest of the ash then gets carried into the atmosphere to become coal-fly ash.<ref name="Schobert, H. H. 2002"/> Methods of reducing these emissions of particulate matter include:
#a [[Baghouse#Fabric filters|baghouse]]
#an [[electrostatic precipitator]] (ESP)
#[[Combined cycle#Integrated Gasification Combined Cycle (IGCC)|cyclone collector]]
The baghouse has a fine filter that collects the ash particles, electrostatic precipitators use an electric field to trap ash particles on high-voltage plates, and cyclone collectors use centrifugal force to trap particles to the walls.<ref name="Schobert, H. H. 2002"/> A recent study indicates that sulfur emissions from fossil fueled power stations in China may have caused a 10-year lull in global warming (1998-2008)<ref>Washington Post 7-5-2011 | http://www.washingtonpost.com/blogs/capital-weather-gang/post/new-study-blames-10-year-lull-in-global-warming-on-china-coal-use-air-pollution/2011/07/05/gHQAwjV8yH_blog.html</ref>

===Radioactive trace elements===
Coal is a sedimentary rock formed primarily from accumulated plant matter, and it includes many inorganic minerals and elements which were deposited along with organic material during its formation. As the rest of the Earth's [[Crust (geology)|crust]], coal also contains low levels of [[uranium]], [[thorium]], and other naturally occurring [[radioactive isotopes]] whose release into the environment leads to [[radioactive contamination]]. While these substances are present as very small trace impurities, enough coal is burned that significant amounts of these substances are released. A 1,000 MW coal-burning power plant could have an uncontrolled release of as much as 5.2 metric tons per year of uranium (containing {{convert|74|lb|kg}} of [[uranium-235]]) and 12.8 metric tons per year of thorium.<ref name="ORNL">[http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html Coal Combustion: Nuclear Resource or Danger?] {{webarchive |url=https://web.archive.org/web/20070205103749/http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html |date=5 February 2007 }} by Alex Gabbard, [[ORNL]] Review, Summer/Fall 1993, Vol. 26, Nos. 3 and 4.</ref> In comparison, a 1,000 MW nuclear plant will generate about 30 metric tons of high-level radioactive solid packed waste per year.<ref>{{cite web|last1=Thompson|first1=Linda|title=Vitrification of Nuclear Waste|url=http://large.stanford.edu/courses/2010/ph240/thompson2/|website=PH240 - Fall 2010: Introduction to the Physics of Energy|publisher=Stanford University|accessdate=10 August 2014}}</ref> It is estimated that during 1982, US coal burning released 155 times as much uncontrolled radioactivity into the atmosphere as the [[Three Mile Island incident]].<ref>[http://www.physics.ohio-state.edu/~aubrecht/coalvsnucMarcon.pdf#page=8 Physics.ohio-state.edu]</ref> The collective radioactivity resulting from all coal burning worldwide between 1937 and 2040 is estimated to be 2,700,000 curies or 0.101 EBq.<ref name="ORNL" /> During normal operation, the effective dose equivalent from coal plants is 100 times that from nuclear plants.<ref name="ORNL" /> Normal operation however, is a deceiving baseline for comparison: just the [[Chernobyl disaster|Chernobyl nuclear disaster]] released, in iodine-131 alone, an estimated 1.76 EBq .<ref name="newscientist1">{{cite web|url=http://www.newscientist.com/article/dn20285-fukushima-radioactive-fallout-nears-chernobyl-levels.html |title=Fukushima radioactive fallout nears Chernobyl levels |publisher=Newscientist.com |accessdate=24 April 2011}}</ref> of radioactivity, a value one order of magnitude above this value for total emissions from all coal burned within a century, while the iodine-131, the major radioactive substance which comes out in accident situations, has a half life of just 8 days.

===Water and air contamination by coal ash===
A study released in August 2010 that examined state pollution data in the United States by the organizations [[Environmental Integrity Project]], the [[Sierra Club]] and [[Earthjustice]] found that coal ash produced by coal-fired power plants dumped at sites across 21 U.S. states has contaminated ground water with toxic elements. The contaminants including the poisons [[arsenic]] and [[lead]].<ref name="mcclatchydc.com">[http://www.mcclatchydc.com/2010/08/26/99728/study-of-coal-ash-sites-finds.html "Study of Coal Ash Sites Finds Extensive Water Contamination"] ''McClatchy''; also archived at: [http://www.commondreams.org/headline/2010/08/27-4 commondreams.org]</ref>

Arsenic has been shown to cause [[skin cancer]], [[bladder cancer]] and [[lung cancer]], and lead damages the [[nervous system]].<ref name=EJ2010>EarthJustice news release, 2010 Sept. 16, [http://unearthed.earthjustice.org/blog/2010-september/new-report-coal-ash-linked-cancer-and-other-maladies "New Report—Coal Ash Linked To Cancer and Other Maladies; Coal's Waste Is Poisoning Communities in 34 States"] {{webarchive |url=https://web.archive.org/web/20100919000203/http://unearthed.earthjustice.org/blog/2010-september/new-report-coal-ash-linked-cancer-and-other-maladies |date=19 September 2010 }} Earthjustice.org and [[Physicians for Social Responsibility]], [http://earthjustice.org/sites/default/files/files/CoalAsh_Earthjustice.pdf "Coal Ash: The Toxic Threat to Our Communities and Our Environment"] 2010 September 16, earthjustice.org</ref> Coal ash contaminants are also linked to respiratory diseases and other health and developmental problems, and have disrupted local aquatic life.<ref name="mcclatchydc.com"/> Coal ash also releases a variety of toxic contaminants into nearby air, posing a health threat to those who breath in fugitive coal dust.
<ref name=EJ2010/>

Currently, the EPA does not regulate the disposal of coal ash; regulation is up to the states and the electric power industry has been lobbying to maintain this status quo. Most states require no monitoring of drinking water near coal ash dump sites. The study found an additional 39 contaminated U.S. sites and concluded that the problem of coal ash-caused water contamination is even more extensive in the United States than has been estimated. The study brought to 137 the number of ground water sites across the United States that are contaminated by power plant-produced coal ash.<ref name="mcclatchydc.com"/>

====Mercury contamination====
{{Main|Mercury (element)}}

U.S. government scientists tested fish in 291 streams around the country for [[mercury contamination]]. They found mercury in every fish tested, according to the study by the [[U.S. Department of the Interior]]. They found mercury even in fish of isolated rural waterways. Twenty five percent of the fish tested had mercury levels above the safety levels determined by the [[U.S. Environmental Protection Agency]] for people who eat the fish regularly. The largest source of mercury contamination in the United States is coal-fueled power plant emissions.<ref>[https://www.nytimes.com/2009/08/20/science/earth/20brfs-MERCURYFOUND_BRF.html?_r=1&em nytimes.com "Mercury Found in Every Fish Tested, Scientists Say"] ''New York Times'', 2009 Aug. 19</ref>

==Greening of fossil fuel power plants==
{{Main|Coal pollution mitigation|Landfill#Reclaiming materials}}
{{Further|Zero Emission Fossil Fuel Power Plants}}
Several methods exist to improve the efficiency of fossil fuel power plants. A frequently used and cost-efficient method is to convert a plant to run on a different fuel. This includes conversions of coal power plants to biomass or waste<ref>[http://www.archives-suez.com/document/?f=developpement-durable/en/awirs_en.pdf Coal to biomass power plant conversion]</ref><ref>[http://www.25x25.org/index.php?option=com_content&task=view&id=579&Itemid=191 Coal to biomass conversion by Georgia Power]</ref><ref>[http://www.ist-world.org/ProjectDetails.aspx?ProjectId=a6556d81d97d41d2be8e31759221b824 Conversion of coal to waste-fired power plant]</ref> and conversions of natural gas power plants to biogas. Conversions of coal powered power plants to waste-fired power plants have an extra benefit in that they can reduce [[landfill]]ing. In addition, waste-fired power plants can be equipped with material recovery, which is also beneficial to the environment. In some instances, [[torrefaction]] of biomass may be needed if biomass is the material the converted fossil fuel power plant will be using.<ref>[https://www.ecn.nl/nl/nieuws/item/successful-test-with-innovative-renewable-energy-source-at-amer-power-plant/ Torrefaction of biomass sometimes needed when using biomass in converted FFPS]</ref>

Improving energy efficiency of a coal-fired power plant also reduces emissions. For example, emissions can be reduced by upgrading existing plants or building new high-efficiency, low-emissions plants. Such plants emit almost 20% less CO2 than a subcritical unit operating at a similar load. Over the longer term, HELE plants can further facilitate emission reductions because coal-fired plants operating at the highest efficiencies are also the most appropriate option for [[carbon capture and storage]] retrofit.<ref>{{cite web
|url= http://cornerstonemag.net/upgrading-the-efficiency-of-the-worlds-coal-fleet-to-reduce-co2-emissions/
|title=Upgrading the Efficiency of the World's Coal Fleet to Reduce CO2 Emissions
|first= Ian
|last= Barnes
|publisher= Cornerstone
|date= March 2015
|accessdate= }}</ref>

Regardless of the conversion, a truly low-carbon fossil fuel power plant implements carbon capture and storage, which means that the exhaust CO2 is not released into the environment and the fossil fuel power plant becomes an [https://web.archive.org/web/20090705094616/http://www.zero-emissionplatform.eu:80/website/library/ emissionless power plant]. A 2006 example of a carbon capture and storage fossil fuel power plant is the pilot Elsam power station near Esbjerg, Denmark.<ref>{{cite web
|url= http://www.ens-newswire.com/ens/mar2006/2006-03-15-06.asp
|title=Europe Tests Carbon Capture at Coal-Fired Power Plant
|last=ENS
|publisher=Environment News Service
|date= March 15, 2006
|accessdate= 15 July 2012}}</ref>

===Coal Pollution Mitigation===
[[Coal pollution mitigation|Coal Pollution Mitigation]] is a process whereby coal is chemically washed of [[mineral]]s and impurities, sometimes [[Gasification|gasified]], burned and the resulting flue gases treated with steam, with the purpose of removing sulfur dioxide, and reburned so as to make the carbon dioxide in the flue gas economically recoverable, and storable underground (the latter of which is called "carbon capture and storage"). The coal industry uses the term "clean coal" to describe technologies designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation and use,<ref>[http://www.australiancoal.com.au/cleanoview.htm AustralianCoal.com.au] {{webarchive |url=https://web.archive.org/web/20071207111230/http://www.australiancoal.com.au/cleanoview.htm |date=7 December 2007 }}—Clean Coal Overview</ref> but has provided no specific quantitative limits on any emissions, particularly carbon dioxide. Whereas contaminants like sulfur or mercury can be removed from coal, carbon cannot be effectively removed while still leaving a usable fuel, and clean coal plants without carbon sequestration and storage do not significantly reduce carbon dioxide emissions. [[James Hansen]] in an open letter to U.S. President [[Barack Obama]] has advocated a "moratorium and phase-out of coal plants that do not capture and store CO2". In his book ''[[Storms of My Grandchildren]]'', similarly, Hansen discusses his ''Declaration of Stewardship'' the first principle of which requires "a moratorium on coal-fired power plants that do not capture and sequester carbon dioxide".<ref>{{Cite book|author=Hansen, James |title=Storms of My Grandchildren |publisher=Bloomsbury Publishing |location=London |year=2009 |isbn=1-4088-0745-9 |page=242 }}</ref>

===Clean gas===
Gas-fired power plants can also be modified to run on [[hydrogen]], the latter of which can be created on-site from natural gas.<ref>[https://energy.gov/eere/fuelcells/hydrogen-production-natural-gas-reforming Natural gas to hydrogen: Natural gas reforming]</ref> Since 2013, the conversion process has been improved by scientists at Karlsruhe Liquid-metal Laboratory (KALLA) as they succeeded in allowing the soot to be easily removed (soot is a byproduct of the process and damaged the working parts in the past -most notably the nickel-iron-cobaltcatalyst-).<ref>[https://www.newscientist.com/article/mg23230940-200-crack-methane-for-fossil-fuels-without-tears/ The reaction that would give us clean fossil fuels forever]</ref><ref>[https://phys.org/news/2013-04-hydrogen-methane-co2-emissions.html Hydrogen from methane without CO2 emissions]</ref> The soot (which contains the carbon) can then be stored underground and is not released into the atmosphere.

==Alternatives to fossil fuel power plants==
{{split section|date=November 2015}}
[[File:U.S. 2014 Electricity Generation By Type.png|thumb|U.S. 2014 Electricity Generation By Type.<ref>[http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01 EIA - Electricity Data]</ref>]]
Alternatives to fossil fuel power plants include [[nuclear power]], [[solar power]], [[geothermal power]], [[wind power]], [[tidal power]], hydroelectric power ([[hydroelectricity]]), [[Biomass|biomass power plants]] and other [[renewable energy|renewable energies]] (see [[non-carbon economy]]). Some of these are proven technologies on an industrial scale (i.e. nuclear, wind, tidal, hydroelectric and biomass fired power) others are still in prototype form.

Nuclear power, and geothermal power may be classed as heat pollutants as they add heat energy to the biosphere that would not otherwise be released.{{Citation needed|date=January 2013}} The net quantity of energy conversion within the biosphere due to the utilisation of wind power, solar power, tidal power, hydroelectric power (hydroelectricity) is static and is derived from the effects of sunlight and the movement of the moon and planets.

Generally, the cost of electrical energy produced by non fossil fuel burning power plants is greater than that produced by burning fossil fuels. This statement however only includes the cost to produce the electrical energy and does not take into account indirect costs associated with the many pollutants created by burning fossil fuels (e.g. increased hospital admissions due to respiratory diseases caused by fine smoke particles).

===Relative cost by generation source===
{{See also|Relative cost of electricity generated by different sources}}

When comparing power plant costs, it is customary to start by calculating the cost of power at the generator terminals by considering several main factors. External costs such as connections costs, the effect of each plant on the distribution grid are considered separately as an additional cost to the calculated power cost at the terminals.

Initial factors considered are:
*Capital costs, including waste disposal and decommissioning costs for nuclear energy.
*Operating and maintenance costs.
*Fuel costs for fossil fuel and biomass sources, and which may be negative for wastes.
*Likely annual hours per year run or load factor, which may be as low as 30% for wind energy, or as high as 90% for nuclear energy.
*Offset sales of heat, for example in combined heat and power district heating (CHP/DH).

These costs occur over the 30–50 year life of the fossil fuel power plants, using [[discounted cash flow]]s. In general large fossil plants are attractive due to their low initial capital costs—typically around £750–£1000 per kilowatt electrical compared to perhaps £1500 per kilowatt for onshore wind.{{Citation needed|date=November 2010}}

==See also==
{{div col||20em|small=yes}}
* [[Biomass]]
* [[Boiler (power generation)]]
* [[Coal analyzer]]
* [[Coal mining]]
* [[Coal power in the United States]]
* [[Combined heat and power]]
* [[Cooling tower system]]
* [[Environmental impact of the coal industry]]
* [[Flue gas stacks]]
* [[Fossil fuel phase-out]]
* [[Geothermal power]]
* [[Global warming]]
* [[Greenhouse gas]]
* [[Mercury vapor turbine]]
* [[Natural gas]]
* [[List of coal power stations]]
* [[List of thermal power station failures]]
* [[Power station]]
* [[Relative cost of electricity generated by different sources]]
* [[Renewable energy power station]]
* [[Steam turbine]]
* [[Thermal power station]]
* [[Water-tube boiler]]
{{div col end}}

==References==
{{Reflist|30em}}

==Bibliography==
*''Steam: Its Generation and Use'' (2005). 41st edition, Babcock & Wilcox Company, {{ISBN|0-9634570-0-4}}
*''Steam Plant Operation'' (2011). 9th edition, Everett B. Woodruff, Herbert B. Lammers, Thomas F. Lammers (coauthors), [[McGraw-Hill]] Professional, {{ISBN|978-0-07-166796-8}}
*''Power Generation Handbook: Fundamentals of Low-Emission, High-Efficiency Power Plant Operation'' (2012). 2nd edition. Philip Kiameh, McGraw-Hill Professional, {{ISBN|978-0-07-177227-3}}
*''Standard Handbook of Powerplant Engineering'' (1997). 2nd edition, Thomas C. Elliott, Kao Chen, Robert Swanekamp (coauthors), McGraw-Hill Professional, {{ISBN|0-07-019435-1}}

==External links==
{{Commons category|Fossil fuel-fired power plants}}
*[http://en.citizendium.org/wiki/Conventional_coal-fired_power_plant Conventional coal-fired power plant]
*{{cite web |url=http://www.tva.gov/power/coalart.htm |title=Power plant diagram |author= |date= |website=tva.gov |publisher=[[Tennessee Valley Authority]] |access-date= |quote=}}
*[https://web.archive.org/web/20060420181534/http://www.marleyct.com:80/wet/ Large industrial cooling towers]
*[http://www.sourcewatch.org/index.php?title=Existing_U.S._Coal_Plants Statistics on existing U.S. coal-fired plants]
*[http://www.whitebunnywabbit.com/news/0945/toxic-fumes-rise-cooling-tower-notices-dangerous-coal-power.html Coal Power more deadly than Nuclear]
*[https://books.google.com/books?id=ZiQDAAAAMBAJ&pg=PA137&dq=popular+science+1949+%22earth+satellite+vehicle%22&hl=en&ei=xCTiTIKFAcWnnQesoInVDw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDEQ6AEwAA#v=onepage&q&f=true '' "Must We Suffer Smoke" '', May 1949, Popular Science] article on early methods of scrubbing emissions from coal-fired power plants
*[https://purl.fdlp.gov/GPO/gpo44902 The Future of Coal: Utilizing America’s Abundant Energy Resources: Hearing before the Subcommittee on Energy, Committee on Science, Space, and Technology, House of Representatives, One Hundred Thirteenth Congress, First Session, July 25, 2013]
*[https://www.youtube.com/watch?v=Hdi4onAQBWQ U.S. President Obama threatens bankruptcy to anyone building a coal-fired power plant in the U.S.] 2008 interview with [[San Francisco Gate]]
*[http://www.power-eng.com/gas.html Gas Power Plant News from Power Engineering Magazine]

{{Authority control}}
{{Portal bar|Energy}}

{{DEFAULTSORT:Fossil Fuel Power Plant}}
[[Category:Fossil fuel power stations| Fossil fuel power station]]
[[Category:Power station technology]]

Reckoner

2017-08-09T21:23:49Z

81.147.69.112:

{{use dmy dates|date=November 2016}}
{{Infobox single
| Name = Reckoner
| Cover = Reckoner.jpg
| Artist = [[Radiohead]]
| Album = [[In Rainbows]]
| A-side =
| Released = 23 September 2008
| Format = [[Music download|Download]]
| Recorded =
| Genre = {{hlist|[[Alternative rock]]|[[art rock]]}}
| Length = 4:50
| Label = [[XL Recordings|XL]]
| Writer = Radiohead
| Producer = {{hlist|[[Nigel Godrich]]|Radiohead}}
| Last single = "[[House of Cards (Radiohead song)|House of Cards]]" / "[[Bodysnatchers (song)|Bodysnatchers]]" (2008)
| This single = "'''Reckoner'''" (2008)
| Next single = "[[All I Need (Radiohead song)|All I Need]]" (2009)
| Misc = }}

"'''Reckoner'''" is a song by the English [[alternative rock]] band [[Radiohead]] from their 2007 album ''[[In Rainbows]]''. It was released as the album's fourth [[single (music)|single]] on 23 September 2008. It was named one of the best songs of the decade by [[Pitchfork (website)|Pitchfork]] and the ''[[NME]]''. [[Remix]]es of the song were released by electronic musicians [[James Holden (producer)|James Holden]], [[Flying Lotus]] and [[Diplo (DJ)|Diplo]]. Radiohead also released the separate [[Stem mixing and mastering|stems]] for fans to remix themselves, as they had they done with their previous single "[[Nude (song)|Nude]]".

==History==
On tour in 2001, Radiohead performed a different, aggressive song with the title "Reckoner" in [[George, Washington]].<ref>{{Cite web|url=http://pitchfork.com/features/article/6707-pitchforks-guide-to-radioheads-in-rainbows/|title=Pitchfork's Guide to Radiohead's In Rainbows {{!}} Pitchfork|website=pitchfork.com|access-date=2016-08-16}}</ref> During a solo performance at a 2005 [[Trade Justice Movement]] show, Radiohead singer [[Thom Yorke]] performed this version of "Reckoner" on acoustic guitar.<ref name=":1">{{Cite web|url=http://www.rollingstone.com/music/pictures/readers-poll-the-10-best-radiohead-songs-20111012/9-reckoner-0654187|title=9. 'Reckoner'|website=Rolling Stone|access-date=2016-08-16}}</ref>

Working on the song for their 2007 album ''[[In Rainbows]]'', Radiohead added a [[Coda (music)|coda]] which developed into a new song, the version of "Reckoner" that appears on the album.<ref>{{cite web|url=http://www.ateaseweb.com/2007/11/19/ed-obrien-thom-yorke-at-bbc-6music/|title=Ed O'Brien & Thom Yorke at BBC 6Music|date=19 November 2007|publisher=[[BBC 6 Music]]|accessdate=23 November 2007}}</ref> In 2009, Yorke released the song originally known as "Reckoner" as a solo single, retitled "[[Feeling Pulled Apart by Horses / The Hollow Earth|Feeling Pulled Apart by Horses]]".<ref name="NME_0903">{{cite web|url=http://www.nme.com/news/radiohead/47120|title=Radiohead's Thom Yorke confirms new single release|date=3 September 2009|publisher=''[[NME]]''|accessdate=3 September 2009}}</ref>

== Composition ==
"Reckoner" features "frosty, clanging" percussion, a "meandering" guitar line, piano, a [[String section|string arrangement]] by Radiohead guitarist [[Jonny Greenwood]], and Yorke's [[falsetto]].<ref name=":0">{{Cite web|url=http://pitchfork.com/reviews/albums/10785-in-rainbows/|title=Radiohead: In Rainbows Album Review {{!}} Pitchfork|website=pitchfork.com|access-date=2016-08-16}}</ref> Yorke said the guitar [[Ostinato|riff]] was a homage to [[Red Hot Chili Peppers]] guitarist [[John Frusciante]], "in my sort of clunky 'can't-really-pick' kind of way".<ref name=":02">{{Cite web|url=http://www.xfm.co.uk/artists/radiohead/interviews/in-rainbows/|title=Radiohead on In Rainbows|last=|first=|date=28 January 2008|website=|publisher=XFM|accessdate=30 January 2015}}</ref>

== Release ==
"Reckoner" was first released on Radiohead's 2007 album ''[[In Rainbows]]''. It was released as the fourth and final [[single (music)|single]] from ''In Rainbows'' on 23 September 2008.<ref>{{cite web|url=http://www.nme.com/news/radiohead/39904|title=Radiohead add 'Reckoner' to fan remix website|date=23 September 2008|publisher=''[[NME]]''|accessdate=16 August 2009}}</ref>

Radiohead had electronic musicians [[James Holden (producer)|James Holden]], [[Flying Lotus]] and [[Diplo (DJ)|Diplo]] create [[remix]]es of "Reckoner".<ref name="pitchfork-remix">{{cite web|url=http://www.pitchforkmedia.com/article/download/145848-new-music-radiohead-reckoner-remixed-by-diplo-flying-lotus-james-holden-mp3s-streams|title=New Music: Radiohead: "Reckoner"|last=Richardson|first=Mark|date=2008-09-23|archiveurl=https://web.archive.org/web/20081210040919/http://www.pitchforkmedia.com/article/download/145848-new-music-radiohead-reckoner-remixed-by-diplo-flying-lotus-james-holden-mp3s-streams|archivedate=2008-12-10|work=[[Pitchfork Media]]|accessdate=2008-09-28}}</ref> As they had done with their previous single "[[Nude (song)|Nude]]", Radiohead also released the separate [[Stem mixing and mastering|stems]] ("Lead Vocal", "Backing Vocal", "Guitars", "Bass", "Drums", and "Piano/Strings") from "Reckoner" for fans to remix.<ref>{{Cite web|url=http://pitchfork.com/news/33531-radiohead-planning-remix-project-for-reckoner/|title=Radiohead Planning Remix Project for "Reckoner" {{!}} Pitchfork|website=pitchfork.com|access-date=2016-08-16}}</ref>

== Reception ==
Reviewing ''In Rainbows'', [[Pitchfork (website)|Pitchfork]] wrote that "Reckoner" "may not be the most immediate track on the album, but over the course of several listens, it reveals itself to be among the most woozily beautiful things the band has ever recorded."<ref name=":0" /> In October 2011, ''Rolling Stone'' readers voted it the ninth best Radiohead song, and ''[[NME]]'' ranked it number 93 on its list of the "150 Best Tracks of the Past 15 Years".<ref name=":1" /><ref>{{cite web|url=http://www.nme.com/list/150-best-tracks-of-the-past-15-years/248648/page/6|title=150 Best Tracks Of The Past 15 Years|date=|website=nme.com|publisher=|access-date=August 6, 2016|quote=|author=}}</ref> Pitchfork listed it #254 on its list of the "Top 500 songs of the 2000s".<ref>{{Cite web|url=http://pitchfork.com/features/lists-and-guides/7685-the-top-500-tracks-of-the-2000s-500-201/?page=2|title=The Top 500 Tracks of the 2000s: 500-201 - Page 2 {{!}} Pitchfork|website=pitchfork.com|access-date=2016-08-16}}</ref>

== Music video ==
The official music video for "Reckoner" is Virtual Lasagna's submission to a video contest conducted by [[Aniboom]]. The video was chosen on 1 October 2008. The video depicts a situation in which a place filled with greenery is being replaced with structures, which hints at the gradual [[deforestation]] of the [[Earth]] for human benefit, but ultimately leads to everything returning to nature.{{Citation needed|date=August 2016}}

==Cover versions==
* [[Gnarls Barkley]] performed a live cover version.<ref>https://soundcloud.com/gmargiani1/gnarls-barkley-reckoner</ref><ref>{{YouTube|RUmmsMeHAaE|Gnarls Barkley - Reckoner (Radiohead cover live HIGH QUALITY)}}</ref>
* Pianist [[Robert Glasper]] recorded the song as a jazz instrumental, released as a promo single for his live album, ''Covered''.<ref name="release">{{cite news|url=http://www.bluenote.com/news/robert-glasper-releases-reckoner|title=Robert Glasper releases "Reckoner"; 1single single from new Trio album|last=|first=|date=2015-04-21|work=[[Blue Note Records]]|accessdate=}}</ref>

==Personnel==
*Thom Yorke
*Colin Greenwood
*Jonny Greenwood
*Ed O'Brien
*Phil Selway

==Charts==

{| class="wikitable"
|-
! Chart !! Peak Position
|-
| [[UK Singles Chart]] || 74<ref>http://acharts.us/song/37975</ref>
|}

==References==
{{reflist|30em}}

==External links==
* {{MetroLyrics song|radiohead|reckoner}}

{{Radiohead}}

[[Category:2007 songs]]
[[Category:2008 singles]]
[[Category:Radiohead songs]]
[[Category:Rock ballads]]
[[Category:XL Recordings singles]]
[[Category:Song recordings produced by Nigel Godrich]]
[[Category:Songs written by Thom Yorke]]
[[Category:Songs written by Colin Greenwood]]
[[Category:Songs written by Jonny Greenwood]]
[[Category:Songs written by Philip Selway]]
[[Category:Songs written by Ed O'Brien]]

Sunshine

2017-08-09T21:23:01Z

81.147.69.112:

{{About|the star}}
{{pp-semi-indef}}
{{pp-move-indef}}
{{Use dmy dates|date=July 2014}}
{{Featured article}}
{{Infobox
| bodystyle = border-collapse:collapse
| title = The Sun [[Image:Sun symbol.svg|25px]]
| image = [[File:Sun white.jpg|290px]]
| caption = Sun with [[sunspot]]s and [[limb darkening]] as seen in [[visible light]] with solar filter.
| headerstyle = background:#FCC857
| labelstyle = padding:2px
| datastyle = padding:2px

| header1 = Observation data
| label2 = Mean distance from [[Earth]]
| data2 = 1 [[astronomical unit|au]] ≈ {{val|1.496|e=8|u=km}} 8 min 19 s at [[speed of light|light speed]]
| label3 = [[Apparent magnitude|Visual brightness]] (''V'')
| data3 = −26.74<ref name=nssdc>{{cite web|last=Williams|first=D. R. |date=1 July 2013 |title=Sun Fact Sheet |url=http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html |publisher=[[NASA Goddard Space Flight Center]] |accessdate=12 August 2013}}</ref>
| label4 = [[Absolute magnitude]]
| data4 = 4.83<ref name=nssdc />
| label5 = [[Spectral classification]]
| data5 = G2V<ref>{{cite book|last=Zombeck|first=Martin V.|date=1990|title=Handbook of Space Astronomy and Astrophysics 2nd edition|publisher=[[Cambridge University Press]]|url=http://ads.harvard.edu/books/hsaa/}}</ref>
| label6 = [[Metallicity]]
| data6 = ''Z'' = 0.0122<ref>{{cite journal |last1=Asplund |first1=M. |last2=Grevesse |first2=N. |last3=Sauval |first3=A. J. |date=2006 |title=The new solar abundances – Part I: the observations |journal=[[Communications in Asteroseismology]] |volume=147 |pages=76–79 |bibcode=2006CoAst.147...76A |doi=10.1553/cia147s76}}</ref>
| label7 = [[Angular size]]
| data7 = 31.6–32.7 [[minutes of arc]]<ref>{{cite web|title=Eclipse 99: Frequently Asked Questions |url=http://education.gsfc.nasa.gov/eclipse/pages/faq.html |publisher=[[NASA]] |accessdate=24 October 2010 |deadurl=yes |archiveurl=https://web.archive.org/web/20100527142627/http://education.gsfc.nasa.gov/eclipse/pages/faq.html |archivedate=27 May 2010 |df= }}</ref>
| label8 = Adjectives
| data8 = Solar
| header10 = [[Orbit]]al characteristics
| label11 = Mean distance from [[Milky Way]] core
| data11 = ≈ {{val|2.7|e=17|u=km}} {{nowrap|{{val|fmt=commas|27200|ul=light-years}}}}
| label12 = [[Galactic year|Galactic period]]
| data12 = (2.25–2.50){{e|8}} [[julian year (astronomy)|yr]]
| label13 = [[Velocity]]
| data13 = ≈ {{val|220|u=km/s}} (orbit around the center of the Milky Way) ≈ {{val|20|u=km/s}} (relative to average velocity of other stars in stellar neighborhood) ≈ {{val|370|u=km/s}}<ref>{{cite journal |last=Hinshaw |first=G. |display-authors=etal |date=2009 |title=Five-year Wilkinson Microwave Anisotropy Probe observations: data processing, sky maps, and basic results |journal=[[The Astrophysical Journal Supplement Series]] |volume=180 |issue=2 |pages=225–245 |arxiv=0803.0732 |bibcode=2009ApJS..180..225H |doi=10.1088/0067-0049/180/2/225}}</ref> (relative to the [[Cosmic microwave background radiation#CMBR dipole anisotropy|cosmic microwave background]])

| header20 = Physical characteristics
| label21 = Equatorial [[radius]]
| data21 = [[Solar radius|695,700]] km<ref name=IAU2015resB3>{{citation | first1=E.E. | last1=Mamajek | first2=A. | last2=Prsa | first3=G. | last3=Torres | first4=al. | last4=et | title=IAU 2015 Resolution B3 on Recommended Nominal Conversion Constants for Selected Solar and Planetary Properties | arxiv=1510.07674}}</ref> {{val|109|u=R_Earth}}<ref name=sse/>
| label22 = Equatorial [[circumference]]
| data22 = {{val|4.379|e=6|u=km}}<ref name=sse/> 109 × Earth<ref name=sse>{{cite web |title=Solar System Exploration: Planets: Sun: Facts & Figures |url=http://solarsystem.nasa.gov/planets/profile.cfm?Object=Sun&Display=Facts&System=Metric |archiveurl=https://web.archive.org/web/20080102034758/http://solarsystem.nasa.gov/planets/profile.cfm?Object=Sun&Display=Facts&System=Metric |archivedate=2 January 2008 |publisher=[[NASA]]
}}</ref>
| label23 = [[Flattening]]
| data23 = {{val|9|e=-6}}
| label24 = [[Surface area]]
| data24 = {{val|6.09|e=12|u=km2}}<ref name=sse/> {{nowrap|{{val|fmt=commas|12000}}}} × Earth<ref name=sse/>
| label25 = [[Volume]]
| data25 = {{val|1.41|e=18|u=km3}}<ref name=sse/> {{nowrap|{{val|fmt=commas|1300000}}}} × Earth
| label26 = [[Mass]]
| data26 = {{val|1.98855|.00025|e=30|u=kg}}<ref name=nssdc/> {{nowrap|{{val|fmt=commas|333000|u=Earth mass}}}}<ref name=nssdc/>
| label27 = Average [[density]]
| data27 = {{val|1.408|u=g/cm3}}<ref name=nssdc/><ref name=sse/><ref>{{cite web |last=Ko |first=M. |date=1999 |title=Density of the Sun |url=http://hypertextbook.com/facts/1999/MayKo.shtml |editor=Elert, G. |work=The Physics Factbook}}</ref> {{val|0.255}} × Earth<ref name=nssdc/><ref name=sse/>
| label28 = Center [[density]] (modeled)
| data28 = {{val|162.2|u=g/cm3}}<ref name=nssdc/> {{val|12.4}} × Earth
| label29 = Equatorial [[surface gravity]]
| data29 = {{val|274.0|u=m/s2}}<ref name=nssdc/> {{val|27.94|u=[[g-force|''g'']]}} {{nowrap|{{val|fmt=commas|27542.29|u=''[[cgs]]''}}}} 28 × Earth<ref name=sse/>
| label30 = [[Moment of inertia factor]]
| data30 = {{val|0.070}}<ref name=nssdc /> (estimate)
| label31 = [[Escape velocity]] (from the surface)
| data31 = {{val|617.7|u=km/s}}<ref name=sse/> 55 × Earth<ref name=sse/>
| label32 = Temperature
| data32 = Center (modeled): {{val|1.57|e=7|u=K}}<ref name=nssdc/> [[Photosphere]] (effective): {{nowrap|{{val|fmt=commas|5772|ul=K}}}}<ref name=nssdc/> [[Corona]]: ≈ {{val|5|e=6|u=K}}
| label33 = [[Luminosity]] (Lsol)
| data33 = {{val|3.828|e=26|ul=W}}<ref name=nssdc/> ≈ {{val|3.75|e=28|u=[[lumen (unit)|lm]]}} ≈ {{val|98|u=lm/W}} [[Luminous efficacy|efficacy]]
| label34 = Mean [[radiance]] (Isol)
| data34 = {{val|2.009|e=7|u=W·m−2·sr−1}}
| label35 = Age
| data35 = ≈ 4.6 billion years<ref name="Bonanno">{{Cite journal |last=Bonanno |first=A. |last2=Schlattl |first2=H. |last3=Paternò |first3=L. |date=2008 |title=The age of the Sun and the relativistic corrections in the EOS |journal=[[Astronomy and Astrophysics]] |volume=390 |issue=3 |pages=1115–1118 |arxiv=astro-ph/0204331 |bibcode=2002A&A...390.1115B |doi=10.1051/0004-6361:20020749 |ref=harv}}</ref><ref>{{Cite journal|url=//www.sciencemag.org/content/338/6107/651.full|title=The Absolute Chronology and Thermal Processing of Solids in the Solar Protoplanetary Disk|date=2 November 2012|accessdate=17 March 2014|doi=10.1126/science.1226919 |journal=Science|volume=338 |issue= 6107 |pages=651–655|bibcode = 2012Sci...338..651C |pmid=23118187 | last1 = Connelly | first1 = JN | last2 = Bizzarro | first2 = M | last3 = Krot | first3 = AN | last4 = Nordlund | first4 = Å | last5 = Wielandt | first5 = D | last6 = Ivanova | first6 = MA}}{{Registration required}}</ref>

| header40 = [[Rotation]] characteristics
| label41 = [[Axial tilt|Obliquity]]
| data41 = 7.25°<ref name=nssdc/> (to the [[ecliptic]]) 67.23° (to the [[galactic plane]])
| label42 = [[Right ascension]] of North pole<ref name="iau-iag">{{cite web |last1=Seidelmann |first1=P. K. |display-authors=etal |title=Report Of The IAU/IAG Working Group On Cartographic Coordinates And Rotational Elements Of The Planets And Satellites: 2000 |url=http://www.hnsky.org/iau-iag.htm |date=2000 |accessdate=22 March 2006}}</ref>
| data42 = 286.13° {{nowrap|19 h 4 min 30 s}}
| label43 = [[Declination]] of North pole
| data43 = +63.87° 63° 52' North
| label44 = Sidereal [[Solar rotation|rotation period]] (at equator)
| data44 = 25.05 d<ref name=nssdc/>
| label45 = (at 16° latitude)
| data45 = 25.38 d<ref name=nssdc/> {{nowrap|25 d 9 h 7 min 12 s}}<ref name="iau-iag"/>
| label46 = (at poles)
| data46 = 34.4 d<ref name=nssdc/>
| label47 = Rotation velocity (at equator)
| data47 = {{val|7.189|e=3|u=km/h}}<ref name="sse"/>

| header50 = [[photosphere|Photospheric]] composition (by mass)
| label51 = [[Hydrogen]]
| data51 = 73.46%<ref>{{cite web |title=The Sun's Vital Statistics |url=http://solar-center.stanford.edu/vitalstats.html |publisher=[[Stanford Solar Center]] |accessdate=29 July 2008}} Citing {{cite book |last=Eddy |first=J. |date=1979 |title=A New Sun: The Solar Results From Skylab |url=https://history.nasa.gov/SP-402/contents.htm |page=37 |publisher=[[NASA]] |id=NASA SP-402}}</ref>
| label52 = [[Helium]]
| data52 = 24.85%
| label53 = [[Oxygen]]
| data53 = 0.77%
| label54 = [[Carbon]]
| data54 = 0.29%
| label55 = [[Iron]]
| data55 = 0.16%
| label56 = [[Neon]]
| data56 = 0.12%
| label57 = [[Nitrogen]]
| data57 = 0.09%
| label58 = [[Silicon]]
| data58 = 0.07%
| label59 = [[Magnesium]]
| data59 = 0.05%
| label60 = [[Sulfur]]
| data60 = 0.04%
}}

The '''Sun''' is the [[star]] at the center of the [[Solar System]]. It is a nearly perfect sphere of hot [[plasma (physics)|plasma]],<ref>
{{Cite news
|url=https://science.nasa.gov/science-news/science-at-nasa/2008/02oct_oblatesun/
|title=How Round is the Sun?
|publisher=NASA
|date=2 October 2008
|accessdate=7 March 2011
}}</ref><ref>
{{Cite news
|url=https://science.nasa.gov/science-news/science-at-nasa/2011/06feb_fullsun/
|title=First Ever STEREO Images of the Entire Sun
|publisher=NASA
|date=6 February 2011
|accessdate=7 March 2011
}}</ref> with internal [[convection|convective]] motion that generates a [[magnetic field]] via a [[Solar dynamo|dynamo process]].<ref name="doi10.1146/annurev-astro-081913-040012">{{Cite journal | doi = 10.1146/annurev-astro-081913-040012| title = Solar Dynamo Theory| journal = Annual Review of Astronomy and Astrophysics| volume = 52| pages = 251–290| year = 2014| last1 = Charbonneau | first1 = P. |bibcode = 2014ARA&A..52..251C }}</ref> It is by far the most important source of [[energy]] for [[life]] on [[Earth]]. Its diameter is about 109 times that of Earth, and [[Solar mass|its mass]] is about 330,000 times that of Earth, accounting for about 99.86% of the total mass of the Solar System.<ref name=Woolfson00>
{{Cite journal
|last=Woolfson |first=M.
|date=2000
|title=The origin and evolution of the solar system
|journal=[[Astronomy & Geophysics]]
|volume=41 |issue=1 |page=12
|bibcode=2000A&G....41a..12W
|doi=10.1046/j.1468-4004.2000.00012.x
|ref=harv
}}</ref>
About three quarters of the Sun's mass consists of [[hydrogen]] (~73%); the rest is mostly [[helium]] (~25%), with much smaller quantities of heavier elements, including [[oxygen]], [[carbon]], [[neon]], and [[iron]].<ref name=basu2008>
{{Cite journal
|last=Basu |first=S.
|last2=Antia |first2=H. M.
|date=2008
|title=Helioseismology and Solar Abundances
|journal=[[Physics Reports]]
|volume=457 |issue=5–6 |pages=217–283
|arxiv=0711.4590
|bibcode=2008PhR...457..217B
|doi=10.1016/j.physrep.2007.12.002
|ref=harv
}}</ref>

The Sun is a [[G-type main-sequence star]] (G2V) based on its [[stellar classification|spectral class]]. As such, it is informally referred to as a yellow dwarf. It formed approximately 4.6 billion<ref group=lower-alpha name=short>All numbers in this article are short scale. One billion is 109, or 1,000,000,000.</ref><ref name="Bonanno" /><ref name="Connelly2012">{{cite journal |title=The Absolute Chronology and Thermal Processing of Solids in the Solar Protoplanetary Disk |journal=[[Science (journal)|Science]] |first1=James N. |last1=Connelly |first2=Martin |last2=Bizzarro |first3=Alexander N. |last3=Krot |first4=Åke |last4=Nordlund |first5=Daniel |last5=Wielandt |first6=Marina A. |last6=Ivanova |volume=338 |issue=6107 |pages=651–655 |date=2 November 2012 |doi=10.1126/science.1226919 |bibcode=2012Sci...338..651C |pmid=23118187}}</ref> years ago from the [[gravitational collapse]] of matter within a region of a large [[molecular cloud]]. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that [[formation and evolution of the Solar System|became the Solar System]]. The central mass became so hot and dense that it eventually initiated [[nuclear fusion]] in its [[solar core|core]]. It is thought that almost all stars [[Star formation|form by this process]].

The Sun is roughly middle-aged; it has not changed dramatically for more than four billion<ref group=lower-alpha name=short /> years, and will remain fairly stable for more than another five billion years. After [[hydrogen fusion]] in its core has diminished to the point at which it is no longer in [[hydrostatic equilibrium]], the core of the Sun will experience a marked increase in density and temperature while its outer layers expand to eventually become a [[red giant]]. It is calculated that the Sun will become sufficiently large to engulf the current orbits of [[Mercury (planet)|Mercury]] and [[Venus]], and render [[Earth]] uninhabitable.

The enormous effect of the Sun on Earth has been recognized since [[prehistoric times]], and the Sun has been [[The Sun in culture|regarded by some cultures]] as a [[solar deity|deity]]. The [[Synodic day|synodic]] rotation of Earth and its orbit around the Sun are the basis of the [[solar calendar]], which is the predominant [[calendar]] in use today.

==Name and etymology==
The English proper name ''Sun'' developed from [[Old English]] ''sunne'' and may be related to ''south''. Cognates to English ''sun'' appear in other [[Germanic languages]], including [[Old Frisian]] ''sunne'', ''sonne'', [[Old Saxon]] ''sunna'', [[Middle Dutch]] ''sonne'', modern [[Dutch language|Dutch]] ''zon'', [[Old High German]] ''sunna'', modern German ''Sonne'', [[Old Norse]] ''sunna'', and [[Gothic language|Gothic]] ''sunnō''. All Germanic terms for the Sun stem from [[Proto-Germanic]] *''sunnōn''.<ref name=BARNHART776>
{{cite book
|last=Barnhart |first=R. K.
|date=1995
|title=The Barnhart Concise Dictionary of Etymology
|page=776
|publisher=[[HarperCollins]]
|isbn=0-06-270084-7
}}</ref><ref name=MALLORY129>
{{cite book
|last=Mallory |first=J. P.
|date=1989
|title=In Search of the Indo-Europeans: Language, Archaeology and Myth
|page=129
|publisher=[[Thames & Hudson]]
|isbn=0-500-27616-1
}}</ref>

The English weekday name ''Sunday'' stems from Old English (''Sunnandæg''; "Sun's day", from before 700) and is ultimately a result of a [[Interpretatio germanica|Germanic interpretation]] of Latin ''dies solis'', itself a translation of the Greek ἡμέρα ἡλίου (''hēméra hēlíou'').<ref name="BARNHART778">
{{cite book
|last=Barnhart |first=R. K.
|date=1995
|title=The Barnhart Concise Dictionary of Etymology
|page=778
|publisher=[[HarperCollins]]
|isbn=0-06-270084-7
}}</ref> The Latin name for the Sun, ''Sol'', is not common in general English language use; the adjectival form is the related word ''solar''.<ref>
{{cite book
|last1=Little |first1=W
|last2=Fowler |first2=H. W.
|last3=Coulson |first3=J.
|chapter=Sol
|title=Oxford Universal Dictionary on Historical Principles
|edition=3rd
|asin=B000QS3QVQ
}}</ref><ref>
{{cite web
|title=Sol
|url=http://www.merriam-webster.com/dictionary/Sol
|publisher=[[Merriam-Webster]]
|accessdate=19 July 2009
}}</ref> The term ''sol'' is also used by planetary astronomers to refer to the duration of a [[solar day]] on another planet, such as [[Mars]].<ref>
{{cite web
|date=15 November 2006
|title=Opportunity's View, Sol 959 (Vertical)
|url=http://www.nasa.gov/mission_pages/mer/images/pia01892.html
|publisher=[[NASA]]
|accessdate=1 August 2007
}}</ref> A mean [[Earth]] solar day is approximately 24 hours, whereas a mean Martian 'sol' is 24 hours, 39 minutes, and 35.244 seconds.<ref>
{{cite web
|last=Allison |first=M.
|last2=Schmunk |first2=R.
|date=8 August 2012
|title=Technical Notes on Mars Solar Time as Adopted by the Mars24 Sunclock
|url=http://www.giss.nasa.gov/tools/mars24/help/notes.html
|publisher=[[NASA]]/[[GISS]]
|accessdate=16 September 2012
}}</ref>

===Religious aspects===

{{main article |Solar deity}}
Solar deities and Sun worship can be found throughout most of recorded history in various forms, including the Egyptian [[Ra]], the Hindu [[Surya]], the Japanese [[Amaterasu]], the Germanic [[Sól (sun)|Sól]], and the Aztec [[Tonatiuh]], among others.

From at least the [[4th Dynasty]] of [[Ancient Egypt]], the Sun was worshipped as the [[Ra|god Ra]], portrayed as a falcon-headed divinity surmounted by the solar disk, and surrounded by a serpent. In the [[New Kingdom of Egypt|New Empire]] period, the Sun became identified with the [[dung beetle]], whose spherical ball of dung was identified with the Sun. In the form of the Sun disc [[Aten]], the Sun had a brief resurgence during the [[Amarna Period]] when it again became the preeminent, if not only, divinity for the [[Pharaoh]] [[Akhenaton]].<ref>{{cite book|last1=Teeter|first1=Emily|title=Religion and Ritual in Ancient Egypt|date=2011|publisher=Cambridge University Press|location=New York|isbn=9780521848558}}</ref><ref>{{cite book|last1=Frankfort|first1=Henri|title=Ancient Egyptian Religion: an Interpretation|date=2011|publisher=Dover Publications|isbn=0486411389}}</ref>

The Sun is viewed as a goddess in [[Germanic paganism]], [[Sól (sun)|Sól/Sunna]].<ref name=MALLORY129/> Scholars theorize that the Sun, as a Germanic goddess, may represent an extension of an earlier [[Proto-Indo-Europeans|Proto-Indo-European]] Sun deity because of [[Indo-European languages|Indo-European linguistic]] connections between Old Norse ''Sól'', [[Sanskrit]] ''[[Surya]]'', [[Gaulish language|Gaulish]] ''[[Sulis]]'', [[Lithuanian language|Lithuanian]] ''[[Saulė]]'', and [[Slavic languages|Slavic]] ''Solntse''.<ref name=MALLORY129/>

In ancient Roman culture, [[Sunday]] was the day of the Sun god. It was adopted as the [[Sabbath]] day by Christians who did not have a Jewish background. The symbol of light was a pagan device adopted by Christians, and perhaps the most important one that did not come from Jewish traditions. In paganism, the Sun was a source of life, giving warmth and illumination to mankind. It was the center of a popular cult among Romans, who would stand at dawn to catch the first rays of sunshine as they prayed. The celebration of the [[winter solstice]] (which influenced Christmas) was part of the Roman cult of the unconquered Sun ([[Sol Invictus]]). Christian churches were built with an orientation so that the congregation faced toward the sunrise in the East.<ref>{{cite book|author=Owen Chadwick|title=A History of Christianity|url=https://books.google.com/books?id=qugouOh3KjMC&pg=PA22|year=1998|publisher=St. Martin's Press|page=22}}</ref>

==Characteristics==

The Sun is a [[G-type main-sequence star]] that comprises about 99.86% of the mass of the Solar System. The Sun has an [[absolute magnitude]] of +4.83, estimated to be brighter than about 85% of the stars in the [[Milky Way]], most of which are [[red dwarf]]s.<ref>{{Cite news
|last=Than |first=K.
|date=2006
|title=Astronomers Had it Wrong: Most Stars are Single
|publisher=[[Space.com]]
|url=http://www.space.com/scienceastronomy/060130_mm_single_stars.html
|accessdate=1 August 2007
}}</ref><ref>{{Cite journal
|last=Lada |first=C. J.
|date=2006
|title=Stellar multiplicity and the initial mass function: Most stars are single
|journal=[[Astrophysical Journal Letters]]
|volume=640 |issue=1 |pages=L63–L66
|arxiv=astro-ph/0601375
|bibcode=2006ApJ...640L..63L
|doi=10.1086/503158
|ref=harv
}}</ref>
The Sun is a [[Population I stars|Population I]], or heavy-element-rich,{{efn|name=heavy elements}} star.<ref name=zeilik>
{{Cite book
|last=Zeilik |first=M. A.
|last2=Gregory |first2=S. A.
|date=1998
|title=Introductory Astronomy & Astrophysics
|edition=4th |page=322
|publisher=[[Saunders College Publishing]]
|isbn=0-03-006228-4
}}</ref> The formation of the Sun may have been triggered by shockwaves from one or more nearby [[supernova]]e.<ref name="Falk">
{{Cite journal
|last=Falk |first=S. W.
|last2=Lattmer |first2=J. M.
|last3=Margolis |first3=S. H.
|date=1977
|title=Are supernovae sources of presolar grains?
|journal=[[Nature (journal)|Nature]]
|volume=270 |issue=5639 |pages=700–701
|bibcode=1977Natur.270..700F
|doi=10.1038/270700a0
|ref=harv
}}</ref> This is suggested by a high [[Abundance of the chemical elements|abundance]] of heavy elements in the Solar System, such as [[gold]] and [[uranium]], relative to the abundances of these elements in so-called [[Population II]], heavy-element-poor, stars. The heavy elements could most plausibly have been produced by [[endothermic]] nuclear reactions during a supernova, or by [[Nuclear transmutation|transmutation]] through [[neutron absorption]] within a massive second-generation star.<ref name=zeilik />

The Sun is by far the brightest object in the Earth's sky, with an [[apparent magnitude]] of −26.74.<ref>{{Cite journal
|last=Burton |first=W. B.
|date=1986
|title=Stellar parameters
|journal=[[Space Science Reviews]]
|volume=43|issue=3–4|pages=244–250
|doi=10.1007/BF00190626
|ref=harv
}}</ref><ref>{{Cite journal
|last=Bessell |first=M. S.
|last2=Castelli |first2=F.
|last3=Plez |first3=B.
|date=1998
|title=Model atmospheres broad-band colors, bolometric corrections and temperature calibrations for O–M stars
|journal=[[Astronomy and Astrophysics]]
|volume=333|pages=231–250
|bibcode=1998A&A...333..231B
|ref=harv
}}</ref> This is about 13 billion times brighter than the next brightest star, [[Sirius]], which has an apparent magnitude of −1.46. The mean distance of the Sun's center to Earth's center is approximately {{convert|1|AU|km mi|lk=in|disp=x| (about |)}}, though the distance varies as Earth moves from [[perihelion]] in January to [[aphelion]] in July.<ref name="USNO">{{cite web
|date=31 January 2008
|title=Equinoxes, Solstices, Perihelion, and Aphelion, 2000–2020
|url=http://aa.usno.navy.mil/data/docs/EarthSeasons.php
|publisher=[[US Naval Observatory]]
|accessdate=17 July 2009
}}</ref> At this average distance, light travels from the Sun's horizon to Earth's horizon in about 8 minutes and 19 seconds, while light from the closest points of the Sun and Earth takes about two seconds less. The energy of this [[sunlight]] supports almost all life<ref group="lower-alpha">[[Hydrothermal vent communities]] live so deep under the sea that they have no access to sunlight. Bacteria instead use sulfur compounds as an energy source, via [[chemosynthesis]].</ref> on Earth by [[photosynthesis]],<ref name="Simon2001">{{Cite book
|last=Simon |first=A.
|title=The Real Science Behind the X-Files : Microbes, meteorites, and mutants
|url=https://books.google.com/?id=1gXImRmz7u8C&pg=PA26&dq=bacteria+that+live+with+out+the+sun
|pages=25–27
|publisher=[[Simon & Schuster]]
|date=2001
|isbn=0-684-85618-2
}}</ref> and drives [[Earth's climate]] and weather.

The Sun does not have a definite boundary, but its density decreases exponentially with increasing height above the [[photosphere]].<ref name="Beer et al, 2012-41">
{{Cite book
|last=Beer |first=J.
|last2=McCracken |first2=K.
|last3=von Steiger |first3=R.
|date=2012
|title=Cosmogenic Radionuclides: Theory and Applications in the Terrestrial and Space Environments
|page=41
|publisher=[[Springer Science+Business Media]]
|isbn=978-3-642-14651-0
}}</ref> For the purpose of measurement, however, the Sun's radius is considered to be the distance from its center to the edge of the photosphere, the apparent visible surface of the Sun.<ref name=Phillips1995-73>
{{Cite book
|last=Phillips |first=K. J. H.
|date=1995
|title=Guide to the Sun
|page=73
|publisher=[[Cambridge University Press]]
|isbn=978-0-521-39788-9
}}</ref> By this measure, the Sun is a near-perfect sphere with an [[oblateness]] estimated at about 9 millionths,<ref name="Godier">{{Cite journal
|last=Godier |first=S.
|last2=Rozelot |first2=J.-P.
|date=2000
|title=The solar oblateness and its relationship with the structure of the tachocline and of the Sun's subsurface
|url=http://aa.springer.de/papers/0355001/2300365.pdf
|journal=[[Astronomy and Astrophysics]]
|volume=355 |pages=365–374
|bibcode=2000A&A...355..365G
|ref=harv
}}</ref> which means that its polar diameter differs from its equatorial diameter by only {{convert|10|km|mi}}.<ref name="perfect sphere">{{cite web
|last=Jones |first=G.
|date=16 August 2012
|title=Sun is the most perfect sphere ever observed in nature
|url=https://www.theguardian.com/science/2012/aug/16/sun-perfect-sphere-nature
|work=[[The Guardian]]
|accessdate=19 August 2013
}}</ref>
The tidal effect of the planets is weak and does not significantly affect the shape of the Sun.<ref name="Schutz2003">{{Cite book
|last=Schutz|first=B. F.
|date=2003
|title=Gravity from the ground up
|pages=98–99
|publisher=[[Cambridge University Press]]
|isbn=978-0-521-45506-0
}}</ref> The Sun rotates faster at its [[equator]] than at its [[poles of astronomical bodies|poles]]. This [[Solar rotation|differential rotation]] is caused by [[convection|convective motion]] due to heat transport and the [[Coriolis effect|Coriolis force]] due to the Sun's rotation. In a frame of reference defined by the stars, the rotational period is approximately 25.6 days at the equator and 33.5 days at the poles. Viewed from Earth as it orbits the Sun, the ''apparent rotational period'' of the Sun at its equator is about 28 days.<ref name="Phillips1995-78">{{Cite book
|last=Phillips|first=K. J. H.
|date=1995
|title=Guide to the Sun
|pages=78–79
|publisher=[[Cambridge University Press]]
|isbn=978-0-521-39788-9
}}</ref>

==Sunlight==
{{Main article|Sunlight}}

The [[solar constant]] is the amount of power that the Sun deposits per unit area that is directly exposed to sunlight. The solar constant is equal to approximately {{val|1368|u=W/m2|fmt=commas}} (watts per square meter) at a distance of one [[astronomical unit]] (AU) from the Sun (that is, on or near Earth).<ref name=TSI>{{cite web|title=Construction of a Composite Total Solar Irradiance (TSI) Time Series from 1978 to present |url=http://www.pmodwrc.ch/pmod.php?topic=tsi/composite/SolarConstant|accessdate = 5 October 2005}}</ref> Sunlight on the surface of Earth is [[attenuation (electromagnetic radiation)|attenuated]] by Earth's atmosphere, so that less power arrives at the surface (closer to {{val|1000|u=W/m2|fmt=commas}}) in clear conditions when the Sun is near the [[zenith]].<ref name=El-Sharkawi2005>{{Cite book|last=El-Sharkawi|first=Mohamed A.|title=Electric energy|date=2005|publisher=CRC Press|isbn=978-0-8493-3078-0|pages=87–88}}</ref> Sunlight at the top of Earth's atmosphere is composed (by total energy) of about 50% infrared light, 40% visible light, and 10% ultraviolet light.<ref name="Solar radiation">[http://curry.eas.gatech.edu/Courses/6140/ency/Chapter3/Ency_Atmos/Radiation_Solar.pdf Solar radiation]</ref> The atmosphere in particular filters out over 70% of solar ultraviolet, especially at the shorter wavelengths.<ref>{{cite web|url=http://rredc.nrel.gov/solar/spectra/am1.5/ |title=Reference Solar Spectral Irradiance: Air Mass 1.5|accessdate=12 November 2009}}</ref> Solar [[ultraviolet radiation]] ionizes Earth's dayside upper atmosphere, creating the electrically conducting [[ionosphere]].<ref name=Phillips1995>
{{Cite book
|last=Phillips |first=K. J. H.
|date=1995
|title=Guide to the Sun
|pages=14–15, 34–38
|publisher=[[Cambridge University Press]]
|isbn=978-0-521-39788-9
}}</ref>

The Sun's color is white, with a [[CIE 1931 color space|CIE]] color-space index near (0.3, 0.3), when viewed from space or when the Sun is high in the sky. When measuring all the photons emitted, the Sun is actually emitting more photons in the green portion of the spectrum than any other.<ref>{{cite web|url=http://www.universetoday.com/18689/color-of-the-sun/|title=What Color is the Sun?|publisher=Universe Today|access-date=23 May 2016}}</ref><ref>{{cite web|url=http://solar-center.stanford.edu/SID/activities/GreenSun.html|title=What Color is the Sun?|publisher=[[Stanford University|Stanford]] Solar Center|access-date=23 May 2016}}</ref> When the Sun is low in the sky, [[Diffuse sky radiation|atmospheric scattering]] renders the Sun yellow, red, orange, or magenta. Despite its typical whiteness, most people mentally picture the Sun as yellow; the reasons for this are the subject of debate.<ref name="yellow sun paradox">
{{Cite journal
|last=Wilk |first=S. R.
|date=2009
|title=The Yellow Sun Paradox
|url=http://www.osa-opn.org/Content/ViewFile.aspx?id=11147
|journal=[[Optics & Photonics News]]
|pages=12–13
|ref=harv
}}</ref>
The Sun is a [[G-type main-sequence star|G2V]] star, with ''G2'' indicating its [[effective temperature|surface temperature]] of approximately 5,778 K (5,505 °C, 9,941 °F), and ''V'' that it, like most stars, is a [[main sequence|main-sequence]] star.<ref name=Phillips1995-47>
{{Cite book
|last=Phillips|first=K. J. H.
|date=1995
|title=Guide to the Sun
|pages=47–53
|publisher=[[Cambridge University Press]]
|isbn=978-0-521-39788-9
}}</ref><ref>{{cite news|title=Dr Karl's Great Moments In Science: Lazy Sun is less energetic than compost |url=http://www.abc.net.au/science/articles/2012/04/17/3478276.htm|accessdate=25 February 2014|newspaper=[[Australian Broadcasting Corporation]]|date=17 April 2012|author=Karl S. Kruszelnicki|quote="Every second, the Sun burns 620 million tonnes of hydrogen..."}}</ref> The average [[luminance]] of the Sun is about 1.88 [[giga]] [[candela per square metre]], but as viewed through Earth's atmosphere, this is lowered to about 1.44 Gcd/m2.{{efn|1=1.88 Gcd/m2 is calculated from the solar illuminance of {{val|128000|u=lux}} (see [[sunlight]]) times the square of the distance to the center of the Sun, divided by the cross sectional area of the Sun. 1.44 Gcd/m2 is calculated using {{val|98000|u=lux}}.}} However, the luminance is not constant across the disk of the Sun ([[limb darkening]]).

==Composition==

{{see also|Molecules in stars}}

The Sun is composed primarily of the [[chemical element]]s [[hydrogen]] and [[helium]]; they account for 74.9% and 23.8% of the mass of the Sun in the photosphere, respectively.<ref name=lodders>
{{cite journal| doi = 10.1086/375492| last = Lodders| first = Katharina| date = July 10, 2003| title = Solar System Abundances and Condensation Temperatures of the Elements| journal = The Astrophysical Journal| publisher = The American Astronomical Society| volume = 591| issue = 2| pages = 1220–1247| url = http://weft.astro.washington.edu/courses/astro557/LODDERS.pdf| format = PDF| bibcode = 2003ApJ...591.1220L| ref = harv}} {{Cite journal
|last=Lodders |first=K.
|title=Abundances and Condensation Temperatures of the Elements
|url=http://www.lpi.usra.edu/meetings/metsoc2003/pdf/5272.pdf
|format=PDF|journal=[[Meteoritics & Planetary Science]]
|volume=38 |issue=suppl. |page=5272
|date=2003
|bibcode=2003M&PSA..38.5272L
|ref=harv
}}</ref> All heavier elements, called ''[[metallicity|metals]]'' in astronomy, account for less than 2% of the mass, with oxygen (roughly 1% of the Sun's mass), carbon (0.3%), neon (0.2%), and iron (0.2%) being the most abundant.<ref name=hkt2004>
{{Cite book
|last=Hansen |first=C.J. |last2=Kawaler |first2=S.A. |last3=Trimble |first3=V.
|title=Stellar Interiors: Physical Principles, Structure, and Evolution
|pages=19–20
|edition=2nd
|publisher=[[Springer Science+Business Media|Springer]]
|date=2004
|isbn=0-387-20089-4
}}</ref>

The Sun inherited its chemical composition from the [[interstellar medium]] out of which it formed. The hydrogen and helium in the Sun were produced by [[Big Bang nucleosynthesis]], and the heavier elements were produced by [[stellar nucleosynthesis]] in generations of stars that completed their [[stellar evolution]] and returned their material to the interstellar medium before the formation of the Sun.<ref name=hkt2004_78>{{Cite book
|last=Hansen |first=C.J. |last2=Kawaler |first2=S.A. |last3=Trimble |first3=V.
|title=Stellar Interiors: Physical Principles, Structure, and Evolution
|pages=77–78
|edition=2nd
|publisher=[[Springer Science+Business Media|Springer]]
|date=2004
|isbn=0-387-20089-4
}}</ref> The chemical composition of the photosphere is normally considered representative of the composition of the primordial Solar System.<ref name="aller1968">
{{Cite journal
|last=Aller |first=L.H.
|title=The chemical composition of the Sun and the solar system
|journal=[[Proceedings of the Astronomical Society of Australia]]
|volume=1 |page=133
|date=1968
|bibcode=1968PASAu...1..133A
|ref=harv
}}</ref> However, since the Sun formed, some of the helium and heavy elements have gravitationally settled from the photosphere. Therefore, in today's photosphere the helium fraction is reduced, and the [[metallicity]] is only 84% of what it was in the [[Protostar|protostellar]] phase (before nuclear fusion in the core started). The protostellar Sun's composition is believed to have been 71.1% hydrogen, 27.4% helium, and 1.5% heavier elements.<ref name=lodders/>

Today, nuclear fusion in the Sun's core has modified the composition by converting hydrogen into helium, so the innermost portion of the Sun is now roughly 60% helium, with the abundance of heavier elements unchanged. Because heat is transferred from the Sun's core by radiation rather than by convection (see [[#Radiative zone|Radiative zone]] below), none of the fusion products from the core have risen to the photosphere.<ref name=hkt2004_9.2.3>{{Cite book
|last=Hansen |first=C.J. |last2=Kawaler |first2=S.A. |last3=Trimble |first3=V.
|title=Stellar Interiors: Physical Principles, Structure, and Evolution
|pages=§ 9.2.3 |nopp=yes
|edition=2nd
|publisher=[[Springer Science+Business Media|Springer]]
|date=2004
|isbn=0-387-20089-4
}}</ref>

The reactive core zone of "hydrogen burning", where hydrogen is converted into helium, is starting to surround an inner core of "helium ash". This development will continue and will eventually cause the Sun to leave the [[main sequence]], to become a [[red giant]].<ref>Iben, I Jnr (1965) "Stellar Evolution. II. The Evolution of a 3 M_{sun} Star from the Main Sequence Through Core Helium Burning". (Astrophysical Journal, vol. 142, p.1447)</ref>

The solar heavy-element abundances described above are typically measured both using [[astronomical spectroscopy|spectroscopy]] of the Sun's photosphere and by measuring abundances in [[meteorites]] that have never been heated to melting temperatures. These meteorites are thought to retain the composition of the protostellar Sun and are thus not affected by settling of heavy elements. The two methods generally agree well.<ref name=basu2008 />

===Singly ionized iron-group elements===
In the 1970s, much research focused on the abundances of [[iron group|iron-group]] elements in the Sun.<ref name="biemont1978">
{{Cite journal
|last=Biemont |first=E.
|date=1978
|title=Abundances of singly ionized elements of the iron group in the Sun
|journal=[[Monthly Notices of the Royal Astronomical Society]]
|volume=184 |pages=683–694
|bibcode=1978MNRAS.184..683B
|ref=harv
|doi=10.1093/mnras/184.4.683
}}</ref><ref>Ross and Aller 1976, Withbroe 1976, Hauge and Engvold 1977, cited in Biemont 1978.</ref> Although significant research was done, until 1978 it was difficult to determine the abundances of some iron-group elements (e.g. [[cobalt]] and [[manganese]]) via [[spectrography]] because of their [[hyperfine structure]]s.<ref name="biemont1978"/>

The first largely complete set of [[oscillator strength]]s of singly ionized iron-group elements were made available in the 1960s,<ref>Corliss and Bozman (1962 cited in Biemont 1978) and Warner (1967 cited in Biemont 1978)</ref> and these were subsequently improved.<ref>Smith (1976 cited in Biemont 1978)</ref> In 1978, the abundances of singly ionized elements of the iron group were derived.<ref name="biemont1978"/>

===Isotopic composition===
Various authors have considered the existence of a gradient in the [[isotope|isotopic]] compositions of solar and planetary [[noble gas]]es,<ref>Signer and Suess 1963; Manuel 1967; Marti 1969; Kuroda and Manuel 1970; Srinivasan and Manuel 1971, all cited in Manuel and Hwaung 1983</ref> e.g. correlations between isotopic compositions of [[neon]] and [[xenon]] in the Sun and on the planets.<ref>Kuroda and Manuel 1970 cited in Manuel and Hwaung 1983:7</ref>

Prior to 1983, it was thought that the whole Sun has the same composition as the solar atmosphere.<ref name="manuel1983">
{{Cite journal
|last=Manuel |first=O. K.
|last2=Hwaung |first2=G.
|date=1983
|title=Solar abundances of the elements
|journal=[[Meteoritics (journal)|Meteoritics]]
|volume=18 |issue=3 |pages=209–222
|bibcode=1983Metic..18..209M
|doi=10.1111/j.1945-5100.1983.tb00822.x
|ref=harv
}}</ref> In 1983, it was claimed that it was [[fractionation]] in the Sun itself that caused the isotopic-composition relationship between the planetary and solar-wind-implanted noble gases.<ref name="manuel1983"/>

==Structure and energy production==

===Core===
{{Main article|Solar core}}

[[File:Sun poster.svg|thumb|x250px|The structure of the Sun]]

The [[Solar core|core]] of the Sun extends from the center to about 20–25% of the solar radius.<ref name="Garcia2007">
{{Cite journal
|last=García |first=R.
|date=2007
|title=Tracking solar gravity modes: the dynamics of the solar core
|journal=[[Science (journal)|Science]]
|volume=316 |issue=5831 |pages=1591–1593
|bibcode=2007Sci...316.1591G
|doi=10.1126/science.1140598
|pmid=17478682
|ref=harv
|display-authors=etal}}</ref> It has a density of up to {{val|150|u=g|up=cm3}}<ref name="Basu">
{{Cite journal
|last1=Basu |first1=S.
|display-authors=etal
|date=2009
|title=Fresh insights on the structure of the solar core
|journal=[[The Astrophysical Journal]]
|volume=699 |issue=2 |pages=1403–1417
|arxiv=0905.0651
|bibcode=2009ApJ...699.1403B
|doi=10.1088/0004-637X/699/2/1403
}}</ref><ref name=NASA1>
{{cite web
|date=18 January 2007
|title=NASA/Marshall Solar Physics
|url=http://solarscience.msfc.nasa.gov/interior.shtml
|publisher=[[Marshall Space Flight Center]]
|accessdate=11 July 2009
}}</ref> (about 150 times the density of water) and a temperature of close to 15.7 million [[kelvin]]s (K).<ref name=NASA1/> By contrast, the Sun's surface temperature is approximately 5,800 K. Recent analysis of [[Solar and Heliospheric Observatory|SOHO]] mission data favors a faster rotation rate in the core than in the radiative zone above.<ref name="Garcia2007"/> Through most of the Sun's life, energy has been produced by [[nuclear fusion]] in the core region through a series of steps called the [[Proton-proton chain reaction|p–p (proton–proton) chain]]; this process converts [[hydrogen]] into [[helium]].<ref>
{{Cite conference
|conference=XXIII Physics in Collisions Conference
|location=Zeuthen, Germany
|last=Broggini |first=C.
|date=2003
|title=Physics in Collision, Proceedings of the XXIII International Conference: Nuclear Processes at Solar Energy
|url=http://www.slac.stanford.edu/econf/C030626
|page=21
|arxiv=astro-ph/0308537
|bibcode=2003phco.conf...21B
|ref=harv
}}</ref> Only 0.8% of the energy generated in the Sun comes from the [[CNO cycle]], though this proportion is expected to increase as the Sun becomes older.<ref name=jpcs271_1_012031>
{{Cite journal
|last1=Goupil |first1=M. J.
|last2=Lebreton |first2=Y.
|last3=Marques |first3=J. P.
|last4=Samadi |first4=R.
|last5=Baudin |first5=F.
|date=2011
|title=Open issues in probing interiors of solar-like oscillating main sequence stars 1. From the Sun to nearly suns
|journal=[[Journal of Physics: Conference Series]]
|volume=271 |issue=1 |page=012031
|arxiv=1102.0247
|bibcode=2011JPhCS.271a2031G
|doi=10.1088/1742-6596/271/1/012031
}}</ref>

The core is the only region in the Sun that produces an appreciable amount of [[thermal energy]] through fusion; 99% of the power is generated within 24% of the Sun's radius, and by 30% of the radius, fusion has stopped nearly entirely. The remainder of the Sun is heated by this energy as it is transferred outwards through many successive layers, finally to the solar photosphere where it escapes into space as sunlight or the [[kinetic energy]] of particles.<ref name=Phillips1995-47/><ref name=Zirker2002-15>
{{Cite book
|last=Zirker|first=J. B.
|date=2002
|title=Journey from the Center of the Sun
|pages=15–34
|publisher=[[Princeton University Press]]
|isbn=978-0-691-05781-1
}}</ref>

The [[proton–proton chain]] occurs around {{val|9.2|e=37}} times each second in the core, converting about 3.7{{e|38}} protons into [[alpha particle]]s (helium nuclei) every second (out of a total of ~8.9{{e|56}} free protons in the Sun), or about 6.2{{e|11}} kg/s.<ref name=Phillips1995-47/> Fusing four free [[proton]]s (hydrogen nuclei) into a single [[alpha particle]] (helium nucleus) releases around 0.7% of the fused mass as energy,<ref>
{{cite book
|last=Shu |first=F. H.
|date=1982
|title=The Physical Universe: An Introduction to Astronomy
|page=102
|publisher=[[University Science Books]]
|isbn=0-935702-05-9
}}</ref> so the Sun releases energy at the mass–energy conversion rate of 4.26 million metric tons per second (which requires 600 metric megatons of hydrogen <ref>{{cite web |title=Ask Us: Sun |url=https://helios.gsfc.nasa.gov/qa_sun.html |work=Cosmicopia |publisher=NASA |date=2012 |accessdate=13 July 2017}}</ref>), for 384.6 [[Yotta-|yottawatts]] ({{val|3.846|e=26|u=W}}),<ref name=nssdc /> or 9.192{{e|10}} [[TNT equivalent|megatons]] of [[Trinitrotoluene|TNT]] per second. Theoretical models of the Sun's interior indicate a power density of approximately 276.5 W/m3,<ref>
{{cite web
|last=Cohen |first=H.
|date=9 November 1998
|title=Table of temperatures, power densities, luminosities by radius in the Sun
|url=http://fusedweb.llnl.gov/CPEP/Chart_Pages/5.Plasmas/Sunlayers.html
|publisher=Contemporary Physics Education Project
|accessdate=30 August 2011
|archiveurl=http://webarchive.loc.gov/all/20011129122524/http%3A//fusedweb%2Ellnl%2Egov/cpep/chart_pages/5%2Eplasmas/sunlayers%2Ehtml |archivedate= 29 November 2001 }}</ref> a value that more nearly approximates that of reptile metabolism or a compost pile<ref>{{cite web|url=http://www.abc.net.au/science/articles/2012/04/17/3478276.htm|title=Lazy Sun is less energetic than compost|date=17 April 2012|publisher=}}</ref> than of a thermonuclear bomb.{{efn|name=power production density}}

The fusion rate in the core is in a self-correcting equilibrium: a slightly higher rate of fusion would cause the core to heat up more and [[thermal expansion|expand]] slightly against the weight of the outer layers, reducing the density and hence the fusion rate and correcting the [[Perturbation (astronomy)|perturbation]]; and a slightly lower rate would cause the core to cool and shrink slightly, increasing the density and increasing the fusion rate and again reverting it to its present rate.<ref>
{{Cite journal
|last1=Haubold |first1=H. J.
|last2=Mathai|first2=A. M.
|date=1994
|title=Solar Nuclear Energy Generation & The Chlorine Solar Neutrino Experiment
|volume=320 |page=102
|journal=[[AIP Conference Proceedings]]
|arxiv=astro-ph/9405040
|bibcode=1995AIPC..320..102H
|doi=10.1063/1.47009
|ref=harv
}}</ref><ref>
{{cite web
|last=Myers|first=S. T.
|date=18 February 1999
|title=Lecture 11 – Stellar Structure I: Hydrostatic Equilibrium
|work=Introduction to Astrophysics II
|accessdate=15 July 2009
|url=http://www.aoc.nrao.edu/~smyers/courses/astro12/L11.html
}}</ref>

===Radiative zone===
{{main article|Radiative zone}}
From the core out to about 0.7 solar radii, [[thermal radiation]] is the primary means of energy transfer.<ref name="autogenerated1">
{{cite web
|url=http://mynasa.nasa.gov/worldbook/sun_worldbook.html
|publisher=NASA|title=Sun
|work=World Book at NASA
|accessdate=10 October 2012
|archiveurl = https://web.archive.org/web/20130510142009/http://mynasa.nasa.gov/worldbook/sun_worldbook.html |archivedate=2013-05-10}}</ref> The temperature drops from approximately 7 million to 2 million kelvins with increasing distance from the core.<ref name=NASA1/> This [[temperature gradient]] is less than the value of the [[adiabatic lapse rate]] and hence cannot drive convection, which explains why the transfer of energy through this zone is by [[radiation]] instead of thermal [[convection]].<ref name=NASA1/> [[Ions]] of [[hydrogen]] and [[helium]] emit [[photons]], which travel only a brief distance before being reabsorbed by other ions.<ref name="autogenerated1"/> The density drops a hundredfold (from 20 g/cm3 to 0.2 g/cm3) from 0.25 solar radii to the 0.7 radii, the top of the radiative zone.<ref name="autogenerated1"/>

===Tachocline===
{{main article|Tachocline}}

The radiative zone and the convective zone are separated by a transition layer, the [[tachocline]]. This is a region where the sharp regime change between the uniform rotation of the radiative zone and the differential rotation of the convection zone results in a large [[shear (fluid)|shear]] between the two—a condition where successive horizontal layers slide past one another.<ref>
{{Cite book
|last=Tobias |first=S. M.
|date=2005
|chapter=The solar tachocline: Formation, stability and its role in the solar dynamo
|url=https://books.google.com/?id=PLNwoJ6qFoEC&pg=PA193
|pages=193–235
|editor=A. M. Soward
|display-editors=etal
|title=Fluid Dynamics and Dynamos in Astrophysics and Geophysics
|publisher=[[CRC Press]]
|isbn=978-0-8493-3355-2
}}</ref> Presently, it is hypothesized (see [[Solar dynamo]]) that a magnetic dynamo within this layer generates the Sun's [[magnetic field]].<ref name=NASA1/>

===Convective zone===
{{main article|Convection zone}}
The Sun's convection zone extends from 0.7 solar radii (200,000 km) to near the surface. In this layer, the solar plasma is not dense enough or hot enough to transfer the heat energy of the interior outward via radiation. Instead, the density of the plasma is low enough to allow convective currents to develop and move the Sun's energy outward towards its surface. Material heated at the tachocline picks up heat and expands, thereby reducing its density and allowing it to rise. As a result, an orderly motion of the mass develops into [[thermal|thermal cells]] that carry the majority of the heat outward to the Sun's photosphere above. Once the material diffusively and radiatively cools just beneath the photospheric surface, its density increases, and it sinks to the base of the convection zone, where it again picks up heat from the top of the radiative zone and the convective cycle continues. At the photosphere, the temperature has dropped to 5,700 K and the density to only 0.2 g/m3 (about 1/6,000 the density of air at sea level).<ref name=NASA1/>

The thermal columns of the convection zone form an imprint on the surface of the Sun giving it a granular appearance called the [[granule (solar physics)|solar granulation]] at the smallest scale and [[supergranulation]] at larger scales. Turbulent convection in this outer part of the solar interior sustains "small-scale" dynamo action over the near-surface volume of the Sun.<ref name=NASA1/> The Sun's thermal columns are [[Bénard cells]] and take the shape of hexagonal prisms.<ref>
{{Cite book
|last=Mullan |first=D. J
|date=2000
|chapter=Solar Physics: From the Deep Interior to the Hot Corona
|url=https://books.google.com/?id=rk5fxs55_OkC&pg=PA22
|page=22
|editor=Page, D.
|editor2=Hirsch, J.G.
|title=From the Sun to the Great Attractor
|publisher=[[Springer Science+Business Media|Springer]]
|isbn=978-3-540-41064-5
}}</ref>

===Photosphere===
[[File:EffectiveTemperature 300dpi e.png|thumb|The [[effective temperature]], or [[black body]] temperature, of the Sun (5,777 K) is the temperature a black body of the same size must have to yield the same total emissive power.]]
{{Main article|Photosphere}}
The visible surface of the Sun, the photosphere, is the layer below which the Sun becomes [[opacity (optics)|opaque]] to visible light.<ref name=Abhyankar1977/> Above the photosphere visible sunlight is free to propagate into space, and almost all of its energy escapes the Sun entirely. The change in opacity is due to the decreasing amount of [[Hydrogen anion|H− ions]], which absorb visible light easily.<ref name=Abhyankar1977/> Conversely, the visible light we see is produced as electrons react with [[hydrogen]] atoms to produce H− ions.<ref name="Gibson">
{{Cite book
|last=Gibson |first=E. G.
|date=1973
|title=The Quiet Sun
|publisher=[[NASA]]
|asin=B0006C7RS0
}}</ref><ref name="Shu">
{{Cite book
|last=Shu |first=F. H.
|title=The Physics of Astrophysics
|volume=1
|publisher=[[University Science Books]]
|date=1991
|isbn=0-935702-64-4
}}</ref>
The photosphere is tens to hundreds of kilometers thick, and is slightly less opaque than air on Earth. Because the upper part of the photosphere is cooler than the lower part, an image of the Sun appears brighter in the center than on the edge or ''limb'' of the solar disk, in a phenomenon known as [[limb darkening]].<ref name=Abhyankar1977/> The spectrum of sunlight has approximately the spectrum of a [[black-body]] radiating at about 6,000 [[kelvin|K]], interspersed with atomic [[absorption line]]s from the tenuous layers above the photosphere. The photosphere has a particle density of ~1023 m−3 (about 0.37% of the particle number per volume of [[Earth's atmosphere]] at sea level). The photosphere is not fully ionized—the extent of ionization is about 3%, leaving almost all of the hydrogen in atomic form.<ref>
{{cite journal
|last1=Rast|first1=M.
|last2=Nordlund |first2=Å.
|last3=Stein |first3=R.
|last4=Toomre |first4=J.
|date=1993
|title=Ionization Effects in Three-Dimensional Solar Granulation Simulations
|journal=[[The Astrophysical Journal Letters]]
|volume=408 |issue=1 |page=L53–L56
|bibcode=1993ApJ...408L..53R
|doi=10.1086/186829
}}</ref>

During early studies of the [[optical spectrum]] of the photosphere, some absorption lines were found that did not correspond to any [[chemical element]]s then known on Earth. In 1868, [[Norman Lockyer]] hypothesized that these absorption lines were caused by a new element that he dubbed ''[[helium]]'', after the Greek Sun god [[Helios]]. Twenty-five years later, helium was isolated on Earth.<ref name="Lockyer">
{{cite web
|last=Parnel |first=C.
|title=Discovery of Helium
|url=http://www-solar.mcs.st-andrews.ac.uk/~clare/Lockyer/helium.html
|publisher=[[University of St Andrews]]
|accessdate=22 March 2006
}}</ref>

===Atmosphere===
{{See also|Corona|Coronal loop}}
[[File:Solar eclipse 1999 4 NR.jpg|thumb|right|During a total [[solar eclipse]], the solar [[corona]] can be seen with the naked eye, during the brief period of totality.]]

During a total [[solar eclipse]], when the disk of the Sun is covered by that of the Moon, parts of the Sun's surrounding atmosphere can be seen. It is composed of four distinct parts: the [[chromosphere]], the [[solar transition region|transition region]], the [[corona]] and the [[heliosphere]].

The coolest layer of the Sun is a temperature minimum region extending to about {{val|500|u=km}} above the photosphere, and has a temperature of about {{val|4100|ul=K|fmt=commas}}.<ref name=Abhyankar1977>
{{Cite journal
|last=Abhyankar |first=K. D.
|date=1977
|title=A Survey of the Solar Atmospheric Models
|url=http://prints.iiap.res.in/handle/2248/510
|journal=[[Bulletin of the Astronomical Society of India]]
|volume=5 |pages=40–44
|bibcode=1977BASI....5...40A
|ref=harv
}}</ref> This part of the Sun is cool enough to allow the existence of simple molecules such as [[carbon monoxide]] and water, which can be detected via their absorption spectra.<ref name=Solanki1994>
{{Cite journal
|last=Solanki |first=S. K.
|last2=Livingston |first2=W.
|last3=Ayres |first3=T.
|date=1994
|title=New Light on the Heart of Darkness of the Solar Chromosphere
|journal=[[Science (journal)|Science]]
|pmid=17748350
|volume=263 |issue=5143 |pages=64–66
|bibcode=1994Sci...263...64S
|doi=10.1126/science.263.5143.64
|ref=harv
}}</ref>

The chromosphere, transition region, and corona are much hotter than the surface of the Sun.<ref name=Abhyankar1977/> The reason is not well understood, but evidence suggests that [[Alfvén wave]]s may have enough energy to heat the corona.<ref>
{{Cite journal
|last=De Pontieu |first=B.
|date=2007
|title=Chromospheric Alfvénic Waves Strong Enough to Power the Solar Wind
|journal=[[Science (journal)|Science]]
|volume=318 |issue=5856 |pages=1574–77
|bibcode=2007Sci...318.1574D
|doi=10.1126/science.1151747
|pmid=18063784
|ref=harv
|display-authors=etal}}</ref>

Above the temperature minimum layer is a layer about {{val|2000|u=km|fmt=commas}} thick, dominated by a spectrum of emission and absorption lines.<ref name=Abhyankar1977/> It is called the ''chromosphere'' from the Greek root ''chroma'', meaning color, because the chromosphere is visible as a colored flash at the beginning and end of total [[solar eclipse]]s.<ref name="autogenerated1"/> The temperature of the chromosphere increases gradually with altitude, ranging up to around {{val|20000|u=K|fmt=commas}} near the top.<ref name=Abhyankar1977/> In the upper part of the chromosphere [[helium]] becomes partially [[ionization|ionized]].<ref name=Hansteen1997>
{{Cite journal
|last=Hansteen |first=V. H.
|last2=Leer |first2=E.
|last3=Holzer |first3=T. E.
|date=1997
|title=The role of helium in the outer solar atmosphere
|journal=[[The Astrophysical Journal]]
|volume=482 |issue=1 |pages=498–509
|bibcode=1997ApJ...482..498H
|doi=10.1086/304111
|ref=harv
}}</ref>

[[File:171879main LimbFlareJan12 lg.jpg|thumb|left|350px|Taken by [[Hinode]]'s Solar Optical Telescope on 12 January 2007, this image of the Sun reveals the filamentary nature of the plasma connecting regions of different magnetic polarity.]]

Above the chromosphere, in a thin (about 200 km) [[solar transition region|transition region]], the temperature rises rapidly from around 20,000 [[kelvin|K]] in the upper chromosphere to coronal temperatures closer to 1,000,000 [[kelvin|K]].<ref name=Erdelyi2007/> The temperature increase is facilitated by the full ionization of helium in the transition region, which significantly reduces radiative cooling of the plasma.<ref name=Hansteen1997/> The transition region does not occur at a well-defined altitude. Rather, it forms a kind of [[Halo (optical phenomenon)|nimbus]] around chromospheric features such as [[Spicule (solar physics)|spicules]] and [[Solar filament|filaments]], and is in constant, chaotic motion.<ref name="autogenerated1"/> The transition region is not easily visible from Earth's surface, but is readily observable from [[outer space|space]] by instruments sensitive to the [[extreme ultraviolet]] portion of the [[electromagnetic spectrum|spectrum]].<ref name=Dwivedi2006>
{{Cite journal
|last=Dwivedi |first=B. N.
|date=2006
|title=Our ultraviolet Sun
|url=http://www.iisc.ernet.in/currsci/sep102006/587.pdf
|journal=[[Current Science]]
|volume=91|issue=5|pages=587–595
|ref=harv
}}</ref>

The [[corona]] is the next layer of the Sun. The low corona, near the surface of the Sun, has a particle density around 1015 m−3 to 1016 m−3.<ref name=Hansteen1997/>{{efn|name=particle density}} The average temperature of the corona and solar wind is about 1,000,000–2,000,000 K; however, in the hottest regions it is 8,000,000–20,000,000 K.<ref name=Erdelyi2007/> Although no complete theory yet exists to account for the temperature of the corona, at least some of its heat is known to be from [[magnetic reconnection]].<ref name=Erdelyi2007/><ref name=Russell2001>
{{Cite book
|last=Russell |first=C. T.
|date=2001
|chapter=Solar wind and interplanetary magnetic filed: A tutorial
|url=http://www-ssc.igpp.ucla.edu/personnel/russell/papers/SolWindTutorial.pdf
|pages=73–88
|editor=Song, Paul
|editor2=Singer, Howard J.
|editor3=Siscoe, George L.
|title=Space Weather (Geophysical Monograph)
|publisher=[[American Geophysical Union]]
|isbn=978-0-87590-984-4
}}</ref>
The corona is the extended atmosphere of the Sun, which has a volume much larger than the volume enclosed by the Sun's photosphere. A flow of plasma outward from the Sun into interplanetary space is the [[solar wind]].<ref name=Russell2001/>

The [[heliosphere]], the tenuous outermost atmosphere of the Sun, is filled with the solar wind plasma. This outermost layer of the Sun is defined to begin at the distance where the flow of the [[solar wind]] becomes ''superalfvénic''—that is, where the flow becomes faster than the speed of [[Alfvén wave]]s,<ref>
{{Cite book
|first=Emslie |last=A. G
|first2=Miller |last2=J. A.
|date=2003
|chapter=Particle Acceleration
|chapterurl=https://books.google.com/books?id=W_oZYFplXX0C&pg=PA275
|editor=Dwivedi, B. N.
|title=Dynamic Sun
|page=275
|publisher=[[Cambridge University Press]]
|isbn=978-0-521-81057-9
}}</ref> at approximately 20 solar radii (0.1 AU).
Turbulence and dynamic forces in the heliosphere cannot affect the shape of the solar corona within, because the information can only travel at the speed of Alfvén waves. The solar wind travels outward continuously through the heliosphere,<ref>{{cite web
|date=22 April 2003
|title=A Star with two North Poles
|url=https://science.nasa.gov/headlines/y2003/22apr_currentsheet.htm
|work=Science @ NASA
|publisher=[[NASA]]
|deadurl=yes
|archiveurl=https://web.archive.org/web/20090718014855/https://science.nasa.gov/headlines/y2003/22apr_currentsheet.htm
|archivedate=18 July 2009
|df=
}}</ref><ref>{{Cite journal
|last=Riley
|first=P.
|last2=Linker
|first2=J. A.
|last3=Mikić
|first3=Z.
|date=2002
|title=Modeling the heliospheric current sheet: Solar cycle variations
|url=http://ulysses.jpl.nasa.gov/science/monthly_highlights/2002-July-2001JA000299.pdf
|journal=[[Journal of Geophysical Research]]
|volume=107
|issue=A7
|pages=SSH 8–1
|bibcode=2002JGRA..107.1136R
|doi=10.1029/2001JA000299
|id=CiteID 1136
|deadurl=yes
|archiveurl=https://web.archive.org/web/20090814052347/http://ulysses.jpl.nasa.gov/science/monthly_highlights/2002-July-2001JA000299.pdf
|archivedate=14 August 2009
|df=
}}</ref> forming the solar magnetic field into a [[Parker spiral|spiral]] shape,<ref name=Russell2001/> until it impacts the [[Heliopause (astronomy)|heliopause]] more than 50 [[Astronomical unit|AU]] from the Sun. In December 2004, the [[Voyager 1]] probe passed through a shock front that is thought to be part of the heliopause.<ref>
{{cite press
|date=2005
|title=The Distortion of the Heliosphere: Our Interstellar Magnetic Compass
|url=http://www.spaceref.com/news/viewpr.html?pid=16394
|publisher=[[European Space Agency]]
|accessdate=22 March 2006
}}</ref> In late 2012 Voyager 1 recorded a marked increase in [[cosmic ray]] collisions and a sharp drop in lower energy particles from the solar wind, which suggested that the probe had passed through the heliopause and entered the [[interstellar medium]].<ref>{{cite book|url=https://books.google.co.uk/books?id=JxauCQAAQBAJ&pg=PA163|title=The Cosmic Compendium: Interstellar Travel|pages=163–4|author=Anderson, Rupert W.|year=2015}}</ref>

===Photons and neutrinos===
{{see also|solar irradiance}}

High-energy [[gamma ray|gamma-ray]] photons initially released with fusion reactions in the core are almost immediately absorbed by the solar plasma of the radiative zone, usually after traveling only a few millimeters. Re-emission happens in a random direction and usually at a slightly lower energy. With this sequence of emissions and absorptions, it takes a long time for radiation to reach the Sun's surface. Estimates of the photon travel time range between 10,000 and 170,000 years.<ref name="NASA">
{{cite web
|date=2007
|title=Ancient sunlight
|url=http://sunearthday.nasa.gov/2007/locations/ttt_sunlight.php
|work=Technology Through Time
|publisher=[[NASA]]
|issue=50
|accessdate=24 June 2009
|ref=harv
}}</ref> In contrast, it takes only 2.3 seconds for the [[neutrino]]s, which account for about 2% of the total energy production of the Sun, to reach the surface. Because energy transport in the Sun is a process that involves photons in thermodynamic equilibrium with matter, the time scale of energy transport in the Sun is longer, on the order of 30,000,000 years. This is the time it would take the Sun to return to a stable state, if the rate of energy generation in its core were suddenly changed.<ref>
{{Cite journal
|last=Stix |first=M.
|date=2003
|title=On the time scale of energy transport in the sun
|url=http://www.springerlink.com/content/l256u14247171u67/
|journal=[[Solar Physics (journal)|Solar Physics]]
|volume=212 |issue=1 |pages=3–6
|bibcode=2003SoPh..212....3S
|doi=10.1023/A:1022952621810
}}</ref>

Neutrinos are also released by the fusion reactions in the core, but, unlike photons, they rarely interact with matter, so almost all are able to escape the Sun immediately. For many years measurements of the number of neutrinos produced in the Sun were [[Solar neutrino problem|lower than theories predicted]] by a factor of 3. This discrepancy was resolved in 2001 through the discovery of the effects of [[neutrino oscillation]]: the Sun emits the number of neutrinos predicted by the [[theory]], but neutrino detectors were missing {{frac|2|3}} of them because the neutrinos had changed [[flavor (particle physics)|flavor]] by the time they were detected.<ref name="Schlattl">
{{Cite journal
|last=Schlattl |first=H.
|date=2001
|title=Three-flavor oscillation solutions for the solar neutrino problem
|journal=[[Physical Review D]]
|volume=64 |issue=1 |page=013009
|arxiv=hep-ph/0102063
|bibcode=2001PhRvD..64a3009S
|doi=10.1103/PhysRevD.64.013009
|ref=harv
}}</ref>

==Magnetism and activity==

===Magnetic field===

{{See also|Stellar magnetic field|Sunspots|List of solar cycles|Solar phenomena}}

[[File:172197main NASA Flare Gband lg-withouttext.jpg|thumb|Visible light photograph of sunspot, 13 December 2006]]

{{Multiple image
| direction = vertical
| width = 350
| image1 = Sunspot butterfly diagram.svg
| image2 = Sunspot area variation.svg
| caption2 = [[Solar cycle#Sunspots|Butterfly diagram]] showing paired sunspot pattern. Graph is of sunspot area.
}}

[[File:Sun - August 1, 2010.jpg|thumb|In this false-color ultraviolet image, the Sun shows a C3-class solar flare (white area on upper left), a solar tsunami (wave-like structure, upper right) and multiple filaments of [[plasma (physics)|plasma]] following a magnetic field, rising from the stellar surface.]]
[[File:Heliospheric-current-sheet.gif|thumb|right|The [[heliospheric current sheet]] extends to the outer reaches of the Solar System, and results from the influence of the Sun's rotating magnetic field on the [[Plasma (physics)|plasma]] in the [[interplanetary medium]].<ref>
{{cite web
|date=2006
|title=The Mean Magnetic Field of the Sun
|url=http://wso.stanford.edu/#MeanField
|publisher=[[Wilcox Solar Observatory]]
|accessdate=1 August 2007
}}</ref>]]

The Sun has a [[magnetic field]] that varies across the surface of the Sun. Its polar field is {{convert|1|-|2|G|sigfig=1|lk=on}}, whereas the field is typically {{convert|3000|G|sigfig=1}} in features on the Sun called [[sunspot]]s and {{convert|10|-|100|G|sigfig=1}} in [[solar prominence]]s.<ref name= nssdc />

The magnetic field also varies in time and location. The quasi-periodic 11-year [[solar cycle]] is the most prominent variation in which the number and size of sunspots waxes and wanes.<ref name="doi10.1146/annurev-astro-081913-040012" /><ref name="Zirker2002-119">{{Cite book
|last=Zirker |first=J. B.
|date=2002
|title=Journey from the Center of the Sun
|pages=119–120
|publisher=[[Princeton University Press]]
|isbn=978-0-691-05781-1
}}</ref><ref name="Lang">{{Cite book
|last=Lang |first=Kenneth R.
|date=2008
|title=The Sun from Space
|page=75
|publisher=[[Springer-Verlag]]
|ISBN=978-3540769521
}}</ref>

Sunspots are visible as dark patches on the Sun's [[photosphere]], and correspond to concentrations of magnetic field where the [[convection|convective transport]] of heat is inhibited from the solar interior to the surface. As a result, sunspots are slightly cooler than the surrounding photosphere, and, so, they appear dark. At a typical [[solar minimum]], few sunspots are visible, and occasionally none can be seen at all. Those that do appear are at high solar latitudes. As the solar cycle progresses towards its [[solar maximum|maximum]], sunspots tend form closer to the solar equator, a phenomenon known as [[Spörer's law]]. The largest sunspots can be tens of thousands of kilometers across.<ref name="Sunspot2001">
{{cite web
|date=30 March 2001
|title=The Largest Sunspot in Ten Years
|url=http://www.gsfc.nasa.gov/gsfc/spacesci/solarexp/sunspot.htm
|publisher=[[Goddard Space Flight Center]]
|accessdate=10 July 2009
|archiveurl = https://web.archive.org/web/20070823050403/http://www.gsfc.nasa.gov/gsfc/spacesci/solarexp/sunspot.htm
|archivedate = 23 August 2007
}}</ref>

An 11-year sunspot cycle is half of a 22-year [[Babcock Model|Babcock]]–Leighton [[solar dynamo|dynamo]] cycle, which corresponds to an oscillatory exchange of energy between [[toroidal and poloidal]] solar magnetic fields. At [[solar maximum|solar-cycle maximum]], the external poloidal dipolar magnetic field is near its dynamo-cycle minimum strength, but an internal [[Toroidal and poloidal|toroidal]] quadrupolar field, generated through differential rotation within the tachocline, is near its maximum strength. At this point in the dynamo cycle, buoyant upwelling within the convective zone forces emergence of toroidal magnetic field through the photosphere, giving rise to pairs of sunspots, roughly aligned east–west and having footprints with opposite magnetic polarities. The magnetic polarity of sunspot pairs alternates every solar cycle, a phenomenon known as the Hale cycle.<ref>{{Cite journal | last1 = Hale | first1 = G. E. | last2 = Ellerman | first2 = F. | last3 = Nicholson | first3 = S. B. | last4 = Joy | first4 = A. H. | title = The Magnetic Polarity of Sun-Spots | journal = The Astrophysical Journal | volume = 49 | page = 153 | year = 1919 | doi = 10.1086/142452|bibcode = 1919ApJ....49..153H }}</ref><ref name="solarcycle">
{{cite web
|date=4 January 2008
|title=NASA Satellites Capture Start of New Solar Cycle
|publisher=[[PhysOrg]]
|url=http://www.physorg.com/news119271347.html
|accessdate=10 July 2009
}}</ref>

During the solar cycle's declining phase, energy shifts from the internal toroidal magnetic field to the external poloidal field, and sunspots diminish in number and size. At [[solar minimum|solar-cycle minimum]], the toroidal field is, correspondingly, at minimum strength, sunspots are relatively rare, and the poloidal field is at its maximum strength. With the rise of the next 11-year sunspot cycle, differential rotation shifts magnetic energy back from the poloidal to the toroidal field, but with a polarity that is opposite to the previous cycle. The process carries on continuously, and in an idealized, simplified scenario, each 11-year sunspot cycle corresponds to a change, then, in the overall polarity of the Sun's large-scale magnetic field.<ref>
{{Cite news
|date=16 February 2001
|title=Sun flips magnetic field
|url=http://edition.cnn.com/2001/TECH/space/02/16/sun.flips/
|work=[[CNN]]
|accessdate=11 July 2009
}}</ref><ref>
{{cite web
|last=Phillips
|first=T.
|date=15 February 2001
|title=The Sun Does a Flip
|url=https://science.nasa.gov/headlines/y2001/ast15feb_1.htm
|publisher=[[NASA]]
|accessdate=11 July 2009
|deadurl=yes
|archiveurl=https://web.archive.org/web/20090512121817/https://science.nasa.gov/headlines/y2001/ast15feb_1.htm
|archivedate=12 May 2009
|df=
}}</ref>

The solar magnetic field extends well beyond the Sun itself. The electrically conducting solar wind plasma carries the Sun's magnetic field into space, forming what is called the [[interplanetary magnetic field]].<ref name=Russell2001/> In an approximation known as ideal [[magnetohydrodynamics]], plasma particles only move along the magnetic field lines. As a result, the outward-flowing solar wind stretches the interplanetary magnetic field outward, forcing it into a roughly radial structure. For a simple dipolar solar magnetic field, with opposite hemispherical polarities on either side of the solar magnetic equator, a thin [[heliospheric current sheet|current sheet]] is formed in the solar wind.<ref name=Russell2001/> At great distances, the rotation of the Sun twists the dipolar magnetic field and corresponding current sheet into an [[Archimedean spiral]] structure called the [[Parker spiral]].<ref name=Russell2001/> The interplanetary magnetic field is much stronger than the dipole component of the solar magnetic field. The Sun's dipole magnetic field of 50–400 [[tesla (unit)|μT]] (at the photosphere) reduces with the inverse-cube of the distance to about 0.1 nT at the distance of Earth. However, according to spacecraft observations the interplanetary field at Earth's location is around 5 nT, about a hundred times greater.<ref name=Wang2003>
{{Cite journal
|last=Wang |first=Y.-M.
|last2=Sheeley |first2=N. R.
|date=2003
|title=Modeling the Sun's Large-Scale Magnetic Field during the Maunder Minimum
|journal=[[The Astrophysical Journal]]
|volume=591 |issue=2 |pages=1248–56
|bibcode=2003ApJ...591.1248W
|doi=10.1086/375449
|ref=harv
}}</ref> The difference is due to magnetic fields generated by electrical currents in the plasma surrounding the Sun.

===Variation in activity===
[[File:Solar-cycle-data.png|thumb|right|Measurements of solar cycle variation during the last 30 years]]

The Sun's magnetic field leads to many effects that are collectively called [[solar variation|solar activity]]. [[Solar flares]] and [[coronal mass ejections|coronal-mass ejections]] tend to occur at sunspot groups. Slowly changing high-speed streams of [[solar wind]] are emitted from [[coronal holes]] at the photospheric surface. Both coronal-mass ejections and high-speed streams of solar wind carry plasma and [[interplanetary magnetic field]] outward into the Solar System.<ref name=Zirker2002>
{{Cite book
|last=Zirker |first=J. B.
|date=2002
|title=Journey from the Center of the Sun
|pages=120–127
|publisher=[[Princeton University Press]]
|isbn=978-0-691-05781-1
}}</ref> The effects of solar activity on Earth include [[aurora (astronomy)|auroras]] at moderate to high latitudes and the disruption of radio communications and [[electric power]]. Solar activity is thought to have played a large role in the [[formation and evolution of the Solar System]].

With solar-cycle modulation of sunspot number comes a corresponding modulation of [[space weather]] conditions, including those surrounding Earth where technological systems can be affected.

===Long-term change===

Long-term secular change in sunspot number is thought, by some scientists, to be correlated with long-term change in solar irradiance,<ref>
{{cite journal
|last=Willson |first=R. C.
|last2=Hudson |first2=H. S.
|date=1991
|title=The Sun's luminosity over a complete solar cycle
|journal=[[Nature (journal)|Nature]]
|volume=351
|issue=6321 |pages=42–4
|doi=10.1038/351042a0
|bibcode = 1991Natur.351...42W }}</ref> which, in turn, might influence Earth's long-term climate.<ref>{{cite journal|authorlink=John A. Eddy|last=Eddy|first=John A.|title=The Maunder Minimum|journal=[[Science (journal)|Science]]|volume=192|issue=4245|pages=1189–1202|date=June 1976|pmid=17771739|doi=10.1126/science.192.4245.1189|jstor=17425839|bibcode=1976Sci...192.1189E}}</ref>
For example, in the 17th century, the solar cycle appeared to have stopped entirely for several decades; few sunspots were observed during a period known as the [[Maunder minimum]]. This coincided in time with the era of the [[Little Ice Age]], when Europe experienced unusually cold temperatures.<ref name="Lean">
{{Cite journal
|last=Lean |first=J.
|last2=Skumanich |first2=A.
|last3=White |first3=O.
|date=1992
|title=Estimating the Sun's radiative output during the Maunder Minimum
|journal=[[Geophysical Research Letters]]
|volume=19 |issue=15 |pages=1591–1594
|doi=10.1029/92GL01578
|ref=harv |bibcode=1992GeoRL..19.1591L
}}</ref> Earlier extended minima have been discovered through analysis of [[tree ring]]s and appear to have coincided with lower-than-average global temperatures.<ref>
{{Cite book
|last=Mackay |first=R. M.
|last2=Khalil |first2=M. A. K
|chapter=Greenhouse gases and global warming
|url= https://books.google.com/?id=tQBS3bAX8fUC&pg=PA1&dq=solar+minimum+dendochronology
|editor=Singh, S. N.
|date=2000
|title=Trace Gas Emissions and Plants
|pages=1–28
|publisher=[[Springer (publisher)|Springer]]
|isbn=978-0-7923-6545-7
}}</ref>

A recent theory claims that there are magnetic instabilities in the core of the Sun that cause fluctuations with periods of either 41,000 or 100,000 years. These could provide a better explanation of the [[ice age]]s than the [[Milankovitch cycles]].<ref>
{{Cite journal
|last=Ehrlich |first=R.
|title=Solar Resonant Diffusion Waves as a Driver of Terrestrial Climate Change
|journal=[[Journal of Atmospheric and Solar-Terrestrial Physics]]
|volume=69 |issue=7 |pages=759–766
|date=2007
|doi=10.1016/j.jastp.2007.01.005
|arxiv=astro-ph/0701117
|ref=harv
|bibcode = 2007JASTP..69..759E }}</ref><ref>
{{Cite journal
|last=Clark |first=S.
|title=Sun's fickle heart may leave us cold
|url=http://www.newscientist.com/article/mg19325884.500-suns-fickle-heart-may-leave-us-cold.html
|journal=[[New Scientist]]
|issue=2588 |page=12
|date=2007
|doi=10.1016/S0262-4079(07)60196-1
|volume=193
|ref=harv
}}</ref>

==Life phases==
{{Main article|Formation and evolution of the Solar System|Stellar evolution}}

The Sun today is roughly halfway through the most stable part of its life. It has not changed dramatically for over four billion<ref group=lower-alpha name=short /> years, and will remain fairly stable for more than five billion more. However, after hydrogen fusion in its core has stopped, the Sun will undergo severe changes, both internally and externally.

===Formation===
The Sun formed about 4.6 billion years ago from the collapse of part of a giant [[molecular cloud]] that consisted mostly of hydrogen and helium and that probably gave birth to many other stars.<ref name=Zirker2002-7>
{{Cite book|last=Zirker|first=Jack B.|title=Journey from the Center of the Sun|date=2002|publisher=[[Princeton University Press]]|isbn=978-0-691-05781-1|pages=7–8}}
</ref> This age is estimated using [[computer simulation|computer models]] of [[stellar evolution]] and through [[nucleocosmochronology]].<ref name="Bonanno"/> The result is consistent with the [[radiometric dating|radiometric date]] of the oldest Solar System material, at 4.567 billion years ago.<ref>
{{Cite journal
|last=Amelin |first=Y. |last2=Krot |first2=A. |last3=Hutcheon |first3=I.
|last4=Ulyanov |first4=A.
|title=Lead isotopic ages of chondrules and calcium-aluminum-rich inclusions
|journal=[[Science (journal)|Science]]
|volume=297 |issue=5587 |pages=1678–1683
|date=2002
|doi=10.1126/science.1073950
|pmid=12215641
|ref=harv
|bibcode = 2002Sci...297.1678A }}</ref><ref name="nature436">
{{Cite journal
|last=Baker |first=J. |last2=Bizzarro |first2=M. |last3=Wittig |first3=N.
|last4=Connelly |first4=J. |last5=Haack |first5=H.
|title=Early planetesimal melting from an age of 4.5662 Gyr for differentiated meteorites
|journal=[[Nature (journal)|Nature]]
|volume=436
|issue=7054|pages=1127–1131
|date=2005
|pmid=16121173
|doi=10.1038/nature03882
|ref=harv
|bibcode = 2005Natur.436.1127B }}</ref> Studies of ancient [[meteorite]]s reveal traces of stable daughter nuclei of short-lived isotopes, such as [[iron-60]], that form only in exploding, short-lived stars. This indicates that one or more supernovae must have occurred near the location where the Sun formed. A [[shock wave]] from a nearby supernova would have triggered the formation of the Sun by compressing the matter within the molecular cloud and causing certain regions to collapse under their own gravity.<ref>{{Cite journal| last1 = Williams | first1 = J.| title = The astrophysical environment of the solar birthplace| journal = Contemporary Physics| volume = 51| issue = 5| pages = 381–396| year = 2010| doi = 10.1080/00107511003764725|bibcode = 2010ConPh..51..381W |arxiv = 1008.2973 }}</ref> As one fragment of the cloud collapsed it also began to rotate because of [[conservation of angular momentum]] and heat up with the increasing pressure. Much of the mass became concentrated in the center, whereas the rest flattened out into a disk that would become the planets and other Solar System bodies. Gravity and pressure within the core of the cloud generated a lot of heat as it accreted more matter from the surrounding disk, eventually triggering [[stellar nucleosynthesis|nuclear fusion]]. Thus, the Sun was born.

===Main sequence===
[[File:Solar evolution (English).svg|right|thumb|320px|Evolution of the Sun's [[Solar luminosity|luminosity]], [[Solar radius|radius]] and [[effective temperature]] compared to the present Sun. After Ribas (2010)<ref name=ribas2010>{{Cite journal | last=Ribas | first=Ignasi |title=Proceedings of the IAU Symposium 264 'Solar and Stellar Variability – Impact on Earth and Planets': The Sun and stars as the primary energy input in planetary atmospheres| volume=264 | pages=3–18 |date=February 2010 | doi=10.1017/S1743921309992298 | bibcode=2010IAUS..264....3R | journal=Proceedings of the International Astronomical Union |arxiv = 0911.4872 }}</ref>]]
The Sun is about halfway through its [[main sequence|main-sequence]] stage, during which nuclear fusion reactions in its core fuse hydrogen into helium. Each second, more than four million [[tonne]]s of matter are converted into energy within the Sun's core, producing [[neutrino]]s and [[solar radiation]]. At this rate, the Sun has so far converted around 100 times the mass of Earth into energy, about 0.03% of the total mass of the Sun. The Sun will spend a total of approximately 10 [[1000000000 (number)|billion]] years as a main-sequence star.<ref>
{{Cite book
|last=Goldsmith |first=D. |last2=Owen |first2=T.
|title=The search for life in the universe
|url=https://books.google.com/?id=Q17NmHY6wloC&pg=PA96
|page=96
|publisher=[[University Science Books]]
|date=2001
|isbn=978-1-891389-16-0
}}</ref> The Sun is gradually becoming hotter during its time on the main sequence, because the helium atoms in the core occupy less volume than the [[hydrogen atom]]s that were fused. The core is therefore shrinking, allowing the outer layers of the Sun to move closer to the centre and experience a stronger gravitational force, according to the [[inverse-square law]]. This stronger force increases the pressure on the core, which is resisted by a gradual increase in the rate at which fusion occurs. This process speeds up as the core gradually becomes denser. It is estimated that the Sun has become 30% brighter in the last 4.5 billion years.<ref>{{cite web|url=http://faculty.wcas.northwestern.edu/~infocom/The%20Website/evolution.html|title=The Sun's Evolution|publisher=}}</ref> At present, it is increasing in brightness by about 1% every 100 million years.<ref>{{cite web|url=http://news.sciencemag.org/climate/2014/01/earth-wont-die-soon-thought|title=Earth Won't Die as Soon as Thought|date=22 January 2014|publisher=}}</ref>

===After core hydrogen exhaustion===

[[File:Sun red giant.svg|thumb|301px|left|The size of the current Sun (now in the [[main sequence]]) compared to its estimated size during its red-giant phase in the future]]
The Sun does not have enough mass to explode as a [[supernova]]. Instead it will exit the [[main sequence]] in approximately 5 billion years and start to turn into a [[red giant]].<ref>{{cite web|author1=Nola Taylor Redd|title=Red Giant Stars: Facts, Definition & the Future of the Sun|url=http://www.space.com/22471-red-giant-stars.html|website=space.com|accessdate=20 February 2016}}</ref><ref name=schroder>{{Cite journal | last1 = Schröder | first1 = K. -P. | last2 = Connon Smith | first2 = R. | doi = 10.1111/j.1365-2966.2008.13022.x | title = Distant future of the Sun and Earth revisited | journal = Monthly Notices of the Royal Astronomical Society | volume = 386 | pages = 155–163 | year = 2008 | pmid = | pmc = |arxiv = 0801.4031 |bibcode = 2008MNRAS.386..155S }}</ref> As a red giant, the Sun will grow so large that it will engulf Mercury, Venus, and probably Earth.<ref name=schroder /><ref name=sackmann>{{Cite journal | last1 = Boothroyd | first1 = A. I. | last2 = Sackmann | first2 = I. ‐J. | doi = 10.1086/306546 | title = The CNO Isotopes: Deep Circulation in Red Giants and First and Second Dredge‐up | journal = The Astrophysical Journal | volume = 510 | pages = 232–250 | year = 1999 | pmid = | pmc = |bibcode = 1999ApJ...510..232B }}</ref>

Even before it becomes a red giant, the luminosity of the Sun will have nearly doubled, and Earth will receive as much sunlight as Venus receives today. Once the core hydrogen is exhausted in 5.4 billion years, the Sun will expand into a [[subgiant]] phase and slowly double in size over about half a billion years. It will then expand more rapidly over about half a billion years until it is over two hundred times larger than today and a couple of thousand times more luminous. This then starts the [[red giant branch|red-giant-branch]] phase where the Sun will spend around a billion years and lose around a third of its mass.<ref name=schroder/>

[[File:Evolution of a Sun-like star.svg|300px|right|thumb|Evolution of a Sun-like star. The track of a one solar mass star on the [[Hertzsprung–Russell diagram]] is shown from the main sequence to the post-asymptotic-giant-branch stage.]]
After the red-giant branch the Sun has approximately 120 million years of active life left, but much happens. First, the core, full of [[degenerate matter|degenerate]] helium ignites violently in the [[helium flash]], where it is estimated that 6% of the core, itself 40% of the Sun's mass, will be converted into carbon within a matter of minutes through the [[triple-alpha process]].<ref>{{cite web|url=http://faculty.wcas.northwestern.edu/~infocom/The%20Website/end.html|title=The End Of The Sun|publisher=}}</ref> The Sun then shrinks to around 10 times its current size and 50 times the luminosity, with a temperature a little lower than today. It will then have reached the [[red clump]] or [[horizontal branch]], but a star of the Sun's mass does not evolve blueward along the horizontal branch. Instead, it just becomes moderately larger and more luminous over about 100 million years as it continues to burn helium in the core.<ref name=schroder/>

When the helium is exhausted, the Sun will repeat the expansion it followed when the hydrogen in the core was exhausted, except that this time it all happens faster, and the Sun becomes larger and more luminous. This is the [[asymptotic giant branch|asymptotic-giant-branch]] phase, and the Sun is alternately burning hydrogen in a shell or helium in a deeper shell. After about 20 million years on the early asymptotic giant branch, the Sun becomes increasingly unstable, with rapid mass loss and [[thermal pulse]]s that increase the size and luminosity for a few hundred years every 100,000 years or so. The thermal pulses become larger each time, with the later pulses pushing the luminosity to as much as 5,000 times the current level and the radius to over 1 AU.<ref name=agb>{{Cite journal | last1 = Vassiliadis | first1 = E. | last2 = Wood | first2 = P. R. | doi = 10.1086/173033 | title = Evolution of low- and intermediate-mass stars to the end of the asymptotic giant branch with mass loss | journal = The Astrophysical Journal | volume = 413 | page = 641 | year = 1993 | pmid = | pmc = |bibcode = 1993ApJ...413..641V }}</ref> According to a 2008 model, Earth's orbit is shrinking due to [[tidal forces]] (and, eventually, drag from the lower [[chromosphere]]), so that it will be engulfed by the Sun near the tip of the red giant branch phase, 1 and 3.8 million years after Mercury and Venus have respectively suffered the same fate. Models vary depending on the rate and timing of mass loss. Models that have higher mass loss on the red-giant branch produce smaller, less luminous stars at the tip of the asymptotic giant branch, perhaps only 2,000 times the luminosity and less than 200 times the radius.<ref name=schroder/> For the Sun, four thermal pulses are predicted before it completely loses its outer envelope and starts to make a [[planetary nebula]]. By the end of that phase – lasting approximately 500,000 years – the Sun will only have about half of its current mass.

The post-asymptotic-giant-branch evolution is even faster. The luminosity stays approximately constant as the temperature increases, with the ejected half of the Sun's mass becoming ionised into a [[planetary nebula]] as the exposed core reaches 30,000 K. The final naked core, a [[white dwarf]], will have a temperature of over 100,000 K, and contain an estimated 54.05% of the Sun's present day mass.<ref name=schroder/> The planetary nebula will disperse in about 10,000 years, but the white dwarf will survive for trillions of years before fading to a hypothetical [[black dwarf]].<ref name=bloecker1>{{bibcode|1995A&A...297..727B}}</ref><ref name=bloecker2>{{bibcode|1995A&A...299..755B}}</ref>

==Motion and location==

===Orbit in Milky Way===

[[File:Artist%27s_impression_of_the_Milky_Way_(updated_-_annotated).jpg|thumb|right|Illustration of the Milky Way, showing the location of the Sun]]

The Sun lies close to the inner rim of the [[Milky Way]]'s [[Orion Arm]], in the [[Local Interstellar Cloud]] or the [[Gould Belt]], at a distance of 7.5–8.5 [[Kiloparsec|kpc]] (25,000–28,000 light-years) from the [[Galactic Center]].<ref>[http://interstellar.jpl.nasa.gov/interstellar/probe/introduction/neighborhood.html, Our Local Galactic Neighborhood, NASA] {{webarchive |url=https://web.archive.org/web/20151107044627/http://interstellar.jpl.nasa.gov/interstellar/probe/introduction/neighborhood.html |date=7 November 2015 }}</ref><ref>{{cite web|url=http://www.centauri-dreams.org/?p=14203|title=Into the Interstellar Void|work=Centauri Dreams}}</ref>
<ref name="distance1">
{{Cite journal
|last=Reid|first=M.J.
|title=The distance to the center of the Galaxy
|journal=[[Annual Review of Astronomy and Astrophysics]]
|date=1993
|volume=31
|issue=1 |pages=345–372
|doi=10.1146/annurev.aa.31.090193.002021
|bibcode=1993ARA&A..31..345R
|ref=harv
}}</ref><ref name="distance2">
{{Cite journal
|last=Eisenhauer |first=F.
|title=A Geometric Determination of the Distance to the Galactic Center
|journal=[[Astrophysical Journal]]
|volume=597 |issue=2 |pages=L121–L124
|date=2003
|doi=10.1086/380188
|bibcode=2003ApJ...597L.121E
|ref=harv
|arxiv = astro-ph/0306220 |display-authors=etal}}</ref><ref name="distance3">
{{Cite journal
|last=Horrobin |first=M.
|title=First results from SPIFFI. I: The Galactic Center
|url=http://www2011.mpe.mpg.de/SPIFFI/preprints/first_result_an1.pdf
|format=PDF|journal=[[Astronomische Nachrichten]]
|volume=325 |issue=2 |pages=120–123
|date=2004
|doi=10.1002/asna.200310181
|ref=harv |bibcode=2004AN....325...88H
|display-authors=etal}}</ref><ref name="eisenhaueretal2005">
{{Cite journal
|last=Eisenhauer |first=F.
|title=SINFONI in the Galactic Center: Young Stars and Infrared Flares in the Central Light-Month
|journal=[[Astrophysical Journal]]
|volume = 628 |issue=1 |pages=246–259
|date=2005
|doi=10.1086/430667
|bibcode=2005ApJ...628..246E
|ref=harv
|arxiv = astro-ph/0502129 |display-authors=etal}}</ref>
The Sun is contained within the [[Local Bubble]], a space of rarefied hot gas, possibly produced by the supernova remnant [[Geminga]].<ref>{{Cite journal|last1=Gehrels|first1=Neil|last2=Chen|first2=Wan|date= 25 February 1993 |title=The Geminga supernova as a possible cause of the local interstellar bubble|journal=Nature|volume=361|issue=6414|pages=706–707|doi=10.1038/361704a0|last3=Mereghetti |first3=S. |ref=harv|bibcode = 1993Natur.361..704B }}</ref> The distance between the local arm and the next arm out, the [[Perseus Arm]], is about 6,500 light-years.<ref name="fn9">
{{cite press
|last=English |first=J.
|title=Exposing the Stuff Between the Stars
|url = http://www.ras.ucalgary.ca/CGPS/press/aas00/pr/pr_14012000/pr_14012000map1.html
|publisher=Hubble News Desk
|date=2000
|accessdate = 10 May 2007
}}</ref> The Sun, and thus the Solar System, is found in what scientists call the [[galactic habitable zone]].
The ''Apex of the Sun's Way'', or the [[solar apex]], is the direction that the Sun travels relative to other nearby stars. This motion is towards a point in the constellation [[Hercules (constellation)|Hercules]], near the star [[Vega]]. Of the 50 [[Nearest stars|nearest stellar systems]] within 17 light-years from Earth (the closest being the red dwarf [[Proxima Centauri]] at approximately 4.2 light-years), the Sun ranks fourth in mass.<ref>{{Cite journal|last=Adams |first=F. C. |last2=Graves |first2=G. |last3=Laughlin |first3=G. J. M. |date=2004 |title=Red Dwarfs and the End of the Main Sequence |url=http://redalyc.uaemex.mx/pdf/571/57102211.pdf |journal=[[Revista Mexicana de Astronomía y Astrofísica]] |volume=22 |pages=46–49 |bibcode=2004RMxAC..22...46A |ref=harv |deadurl=yes |archiveurl=https://web.archive.org/web/20110726103734/http://redalyc.uaemex.mx/pdf/571/57102211.pdf |archivedate=26 July 2011 }}</ref>

The Sun orbits the center of the Milky Way, and it is presently moving in the direction of constellation of [[Cygnus (constellation)|Cygnus]]. The Sun's orbit around the Milky Way is roughly elliptical with orbital perturbations due to the non-uniform mass distribution in Milky Way, such as that in and between the galactic spiral arms. In addition, the Sun oscillates up and down relative to the galactic plane approximately 2.7 times per orbit.<ref>{{cite book|last1=Moore|first1=Patrick|last2=Rees|first2=Robin|title=Patrick Moore's Data Book of Astronomy|date=16 January 2014|publisher=Cambridge University Press|location=[[Cambridge]]|isbn=1139495224|ref=harv}}</ref> It has been argued that the Sun's passage through the higher density spiral arms often coincides with [[mass extinction]]s on Earth, perhaps due to increased [[impact events]].<ref name="extinction">{{Cite journal |last=Gillman |first=M. |last2=Erenler |first2=H. |title=The galactic cycle of extinction |journal=[[International Journal of Astrobiology]] |volume=7 | issue = 1 | pages=17–26 |date=2008 |doi=10.1017/S1473550408004047 |ref=harv |bibcode=2008IJAsB...7...17G}}</ref> It takes the Solar System about 225–250 million years to complete one orbit through the Milky Way (a ''[[galactic year]]''),<ref name="fn10">
{{cite web |last=Leong |first=S. |title=Period of the Sun's Orbit around the Galaxy (Cosmic Year) |url=http://hypertextbook.com/facts/2002/StacyLeong.shtml |work=The Physics Factbook |date=2002 |accessdate=10 May 2007}}</ref> so it is thought to have completed 20–25 orbits during the lifetime of the Sun. The [[orbital speed]] of the Solar System about the center of the Milky Way is approximately 251 km/s (156 mi/s).<ref name="space.newscientist.com">{{Cite journal |last=Croswell |first=K. |date=2008 |title=Milky Way keeps tight grip on its neighbor |url=http://www.newscientist.com/article/dn12652-milky-way-keeps-a-light-grip-on-speedy-neighbours.html#.VQ7JD46WnCY |journal=[[New Scientist]] |volume=199 |issue=2669 |page=8 |doi=10.1016/S0262-4079(08)62026-6 |ref=harv}}</ref> At this speed, it takes around 1,190 years for the Solar System to travel a distance of 1 light-year, or 7 days to travel 1 [[Astronomical unit|AU]].<ref>{{Cite book |last=Garlick |first=M.A. |title=The Story of the Solar System |page=46 |publisher=[[Cambridge University Press]] |date=2002 |isbn=0-521-80336-5}}</ref>

The Milky Way is moving with respect to the [[cosmic microwave background radiation]] (CMB) in the direction of the constellation [[Hydra (constellation)|Hydra]] with a speed of 550 km/s, and the Sun's resultant velocity with respect to the CMB is about 370 km/s in the direction of [[Crater (constellation)|Crater]] or [[Leo (constellation)|Leo]].<ref>{{Cite journal
|last=Kogut |first=A.
|date=1993
|title=Dipole Anisotropy in the COBE Differential Microwave Radiometers First-Year Sky Maps
|journal=[[Astrophysical Journal]]
|volume=419 |page=1
|arxiv=astro-ph/9312056
|doi=10.1086/173453
|bibcode = 1993ApJ...419....1K |display-authors=etal}}</ref>

==Theoretical problems==
[[File:Map of the full sun.jpg|thumb|Map of the full Sun by STEREO and [[Solar Dynamics Observatory|SDO]] spacecraft]]

===Coronal heating problem===
{{Main article|Corona}}
The temperature of the photosphere is approximately 6,000 K, whereas the temperature of the corona reaches 1,000,000–2,000,000 K.<ref name=Erdelyi2007/> The high temperature of the corona shows that it is heated by something other than direct [[heat conduction]] from the photosphere.<ref name=Russell2001/>

It is thought that the energy necessary to heat the corona is provided by turbulent motion in the convection zone below the photosphere, and two main mechanisms have been proposed to explain coronal heating.<ref name=Erdelyi2007/> The first is [[wave]] heating, in which sound, gravitational or magnetohydrodynamic waves are produced by turbulence in the convection zone.<ref name=Erdelyi2007/> These waves travel upward and dissipate in the corona, depositing their energy in the ambient matter in the form of heat.<ref name="Alfven">{{Cite journal |last=Alfvén |first=H. |title=Magneto-hydrodynamic waves, and the heating of the solar corona |journal=[[Monthly Notices of the Royal Astronomical Society]] |volume=107 |issue=2 |pages=211–219 |date=1947 |bibcode=1947MNRAS.107..211A |ref=harv |doi=10.1093/mnras/107.2.211}}</ref> The other is [[magnetic field|magnetic]] heating, in which magnetic energy is continuously built up by photospheric motion and released through [[magnetic reconnection]] in the form of large [[solar flare]]s and myriad similar but smaller events—[[nanoflares]].<ref name="Parker2">{{Cite journal |last=Parker |first=E.N. |title=Nanoflares and the solar X-ray corona |journal=[[Astrophysical Journal]] |volume=330 |issue=1 |page=474 |date=1988 |doi=10.1086/166485 |bibcode=1988ApJ...330..474P |ref=harv}}</ref>

Currently, it is unclear whether waves are an efficient heating mechanism. All waves except [[Alfvén wave]]s have been found to dissipate or refract before reaching the corona.<ref name="Sturrock">{{Cite journal |last=Sturrock |first=P.A. |last2=Uchida |first2=Y. |title=Coronal heating by stochastic magnetic pumping |journal=[[Astrophysical Journal]] |volume=246 |issue=1 |page=331 |date=1981 |doi=10.1086/158926 |bibcode=1981ApJ...246..331S |ref=harv}}</ref> In addition, Alfvén waves do not easily dissipate in the corona. Current research focus has therefore shifted towards flare heating mechanisms.<ref name=Erdelyi2007>{{Cite journal|last=Erdèlyi|first=R.|last2=Ballai|first2=I.|title=Heating of the solar and stellar coronae: a review |date=2007 |journal=Astron. Nachr. |volume=328 |issue=8 |pages=726–733 |doi=10.1002/asna.200710803 |ref=harv |bibcode=2007AN....328..726E}}</ref>

===Faint young Sun problem===
{{Main article|Faint young Sun paradox}}

Theoretical models of the Sun's development suggest that 3.8 to 2.5 billion years ago, during the [[Archean|Archean eon]], the Sun was only about 75% as bright as it is today. Such a weak star would not have been able to sustain liquid water on Earth's surface, and thus life should not have been able to develop. However, the geological record demonstrates that Earth has remained at a fairly constant temperature throughout its history, and that the young Earth was somewhat warmer than it is today. One theory among scientists is that the atmosphere of the young Earth contained much larger quantities of [[greenhouse gas]]es (such as [[carbon dioxide]], [[methane]]) than are present today, which trapped enough heat to compensate for the smaller amount of [[solar energy]] reaching it.<ref name="Kasting">
{{Cite journal
|last=Kasting |first=J.F.
|last2=Ackerman |first2=T.P.
|title=Climatic Consequences of Very High Carbon Dioxide Levels in the Earth's Early Atmosphere
|journal=[[Science (journal)|Science]]
|volume=234 |issue=4782 |pages=1383–1385
|date=1986
|doi=10.1126/science.11539665
|pmid=11539665
|ref=harv
}}</ref>

However, examination of Archaean sediments appears inconsistent with the hypothesis of high greenhouse concentrations. Instead, the moderate temperature range may be explained by a lower surface [[albedo]] brought about by less continental area and the "lack of biologically induced cloud condensation nuclei". This would have led to increased absorption of solar energy, thereby compensating for the lower solar output.<ref name = "Rosing">{{cite journal
|author1=Rosing, Minik T. |author2=Bird, Dennis K. |author3=Sleep, Norman H. |author4=Bjerrum, Christian J. | title=No climate paradox under the faint early Sun
| journal=Nature | volume=464
| issue=7289 | pages=744–747
| date=April 1, 2010
| pmid=20360739 | doi=10.1038/nature08955 |bibcode = 2010Natur.464..744R }}</ref>

==History of observation==

The enormous effect of the Sun on Earth has been recognized since [[prehistoric times]], and the Sun has been [[solar deity|regarded by some cultures]] as a [[deity]].

===Early understanding===
[[File:Solvognen DO-6865 2000.jpg|thumb|right|The [[Trundholm sun chariot]] pulled by a horse is a sculpture believed to be illustrating an important part of [[Nordic Bronze Age]] mythology. The sculpture is probably from around 1350 [[Anno Domini|BC]]. It is displayed at the [[National Museum of Denmark]].]]
{{See also|The Sun in culture}}
The Sun has been an object of veneration in many cultures throughout human history. Humanity's most fundamental understanding of the Sun is as the luminous disk in the [[sky]], whose presence above the [[horizon]] creates day and whose absence causes night. In many prehistoric and ancient cultures, the Sun was thought to be a [[solar deity]] or other [[supernatural]] entity. [[Sun worship|Worship of the Sun]] was central to civilizations such as the [[ancient Egypt]]ians, the [[Inca]] of South America and the [[Aztec]]s of what is now [[Mexico]]. In religions such as [[Hinduism]], the Sun is still considered a god. Many ancient monuments were constructed with solar phenomena in mind; for example, stone [[megalith]]s accurately mark the summer or winter [[solstice]] (some of the most prominent megaliths are located in [[Nabta Playa]], [[Egypt]]; [[Mnajdra]], Malta and at [[Stonehenge]], England); [[Newgrange]], a prehistoric human-built mount in Ireland, was designed to detect the winter solstice; the pyramid of [[El Castillo, Chichen Itza|El Castillo]] at [[Chichén Itzá]] in Mexico is designed to cast shadows in the shape of serpents climbing the [[pyramid]] at the vernal and autumnal [[equinox]]es.

The Egyptians portrayed the god [[Ra]] as being carried across the sky in a solar barque, accompanied by lesser gods, and to the Greeks, he was [[Helios]], carried by a chariot drawn by fiery horses. From the reign of [[Elagabalus]] in the [[Decline of the Roman Empire|late Roman Empire]] the Sun's birthday was a holiday celebrated as [[Sol Invictus]] (literally "Unconquered Sun") soon after the winter solstice, which may have been an antecedent to Christmas. Regarding the [[fixed star]]s, the Sun appears from Earth to revolve once a year along the [[ecliptic]] through the [[zodiac]], and so Greek astronomers categorized it as one of the seven [[classical planets|planets]] (Greek ''planetes'', "wanderer"); the naming of the [[Names of the days of the week|days of the weeks]] after the seven planets dates to the [[Roman Empire|Roman era]].<ref name=oed>{{cite web| url= http://www.oxforddictionaries.com/definition/american_english/planet|publisher = Oxford Dictionaries| title = Planet| accessdate=22 March 2015|date=December 2007}}</ref><ref name=almagest>{{Cite journal|first=Bernard R.|last=Goldstein|title=Saving the phenomena : the background to Ptolemy's planetary theory| journal=Journal for the History of Astronomy|volume=28|issue=1|date=1997|pages=1–12|location=Cambridge (UK) |bibcode=1997JHA....28....1G|ref=harv}}</ref><ref>{{Cite book|title=Ptolemy's Almagest|author= Ptolemy|last2=Toomer|first2=G. J.|publisher=Princeton University Press|date=1998|isbn=978-0-691-00260-6}}</ref>

===Development of scientific understanding===

In the early first millennium BC, [[Babylonian astronomy|Babylonian astronomers]] observed that the Sun's motion along the ecliptic is not uniform, though they did not know why; it is today known that this is due to the movement of [[Earth]] in an [[elliptic orbit]] around the Sun, with Earth moving faster when it is nearer to the Sun at [[Apsis|perihelion]] and moving slower when it is farther away at [[Apsis|aphelion]].<ref>{{Cite book|title=Babylon to Voyager and beyond: a history of planetary astronomy|first=David|last=Leverington|publisher=[[Cambridge University Press]]|date=2003|isbn=0-521-80840-5|pages=6–7|ref=harv|postscript=}}</ref>

One of the first people to offer a scientific or philosophical explanation for the Sun was the [[Ancient Greece|Greek]] [[philosopher]] [[Anaxagoras]]. He reasoned that it was not the [[chariot]] of [[Helios]], but instead a giant flaming ball of metal even larger than the land of the [[Peloponnese|Peloponnesus]] and that the [[Moon]] reflected the light of the Sun.<ref>
{{Cite journal
|last=Sider |first=D.
|title=Anaxagoras on the Size of the Sun
|jstor=269068
|journal=[[Classical Philology (journal)|Classical Philologys]]
|volume=68 |issue=2 |pages=128–129
|date=1973
|doi=10.1086/365951
|ref=harv
}}</ref> For teaching this [[heresy]], he was imprisoned by the authorities and [[capital punishment|sentenced to death]], though he was later released through the intervention of [[Pericles]]. [[Eratosthenes]] estimated the distance between Earth and the Sun in the 3rd century BC as "of stadia [[myriad]]s 400 and 80000", the translation of which is ambiguous, implying either 4,080,000 [[Stadion (unit)|stadia]] (755,000 km) or 804,000,000 stadia (148 to 153 million kilometers or 0.99 to 1.02 AU); the latter value is correct to within a few percent. In the 1st century AD, [[Ptolemy]] estimated the distance as 1,210 times [[Earth radius|the radius of Earth]], approximately {{convert|{{#expr:1.210*6.371round2}}|e6km|AU|sp=us}}.<ref>
{{Cite journal
|last=Goldstein |first=B.R.
|title=The Arabic Version of Ptolemy's Planetary Hypotheses
|journal=[[Transactions of the American Philosophical Society]]
|volume=57 |issue=4 |pages=9–12
|date=1967
|doi=10.2307/1006040
|ref=harv
|jstor=1006040
}}</ref>

The theory that the Sun is the center around which the planets orbit was first proposed by the ancient Greek [[Aristarchus of Samos]] in the 3rd century BC, and later adopted by [[Seleucus of Seleucia]] (see [[Heliocentrism]]). This view was developed in a more detailed [[mathematical model]] of a heliocentric system in the 16th century by [[Nicolaus Copernicus]].

Observations of sunspots were recorded during the [[Han Dynasty]] (206 BC–AD 220) by [[Chinese astronomy|Chinese astronomers]], who maintained records of these observations for centuries. [[Averroes]] also provided a description of sunspots in the 12th century.<ref>
{{cite book |last=Ead |first=Hamed A. |title=Averroes As A Physician |publisher=[[University of Cairo]]}}</ref> The invention of the [[telescope]] in the early 17th century permitted detailed observations of [[sunspot]]s by [[Thomas Harriot]], [[Galileo Galilei]] and other astronomers. Galileo posited that sunspots were on the surface of the Sun rather than small objects passing between Earth and the Sun.<ref>
{{cite web
|title=Galileo Galilei (1564–1642)
|url=http://www.bbc.co.uk/history/historic_figures/galilei_galileo.shtml
|publisher=BBC
|accessdate=22 March 2006
}}</ref>

[[Astronomy in medieval Islam|Arabic astronomical contributions]] include [[Muhammad ibn Jābir al-Harrānī al-Battānī|Albatenius]]' discovery that the direction of the Sun's [[apogee]] (the place in the Sun's orbit against the fixed stars where it seems to be moving slowest) is changing.<ref>''A short History of scientific ideas to 1900'', C. Singer, Oxford University Press, 1959, p. 151.</ref> (In modern heliocentric terms, this is caused by a gradual motion of the aphelion of the ''Earth's'' orbit). [[Ibn Yunus]] observed more than 10,000 entries for the Sun's position for many years using a large [[astrolabe]].<ref>The Arabian Science, C. Ronan, pp. 201–244 in ''The Cambridge Illustrated History of the World's Science'', Cambridge University Press, 1983; at pp. 213–214.</ref>

[[File:Sun-bonatti.png|thumb|Sol, the Sun, from a 1550 edition of [[Guido Bonatti]]'s ''Liber astronomiae''.]]
From an observation of a [[transit of Venus]] in 1032, the Persian astronomer and polymath [[Avicenna]] concluded that Venus is closer to Earth than the Sun.<ref name=Goldstein>{{Cite journal|title=Theory and Observation in Medieval Astronomy|first=Bernard R.|last=Goldstein|journal=[[Isis (journal)|Isis]]|volume=63|issue=1|date=March 1972|publisher=[[University of Chicago Press]]|pages=39–47 [44]|doi=10.1086/350839|ref=harv}}</ref> In 1672 [[Giovanni Cassini]] and [[Jean Richer]] determined the distance to [[Mars]] and were thereby able to calculate the distance to the Sun.

In 1666, [[Isaac Newton]] observed the Sun's light using a [[prism (optics)|prism]], and showed that it is made up of light of many colors.<ref>
{{cite web
|title=Sir Isaac Newton (1643–1727)
|url=http://www.bbc.co.uk/history/historic_figures/newton_isaac.shtml
|publisher=BBC
|accessdate=22 March 2006
}}</ref> In 1800, [[William Herschel]] discovered [[infrared]] radiation beyond the red part of the solar spectrum.<ref>
{{cite web
|title=Herschel Discovers Infrared Light
|url=http://coolcosmos.ipac.caltech.edu/cosmic_classroom/classroom_activities/herschel_bio.html
|publisher=Cool Cosmos
|accessdate=22 March 2006
|deadurl=yes
|archiveurl=https://web.archive.org/web/20120225094516/http://coolcosmos.ipac.caltech.edu/cosmic_classroom/classroom_activities/herschel_bio.html
|archivedate=25 February 2012
|df=
}}</ref> The 19th century saw advancement in spectroscopic studies of the Sun; [[Joseph von Fraunhofer]] recorded more than 600 [[absorption lines]] in the spectrum, the strongest of which are still often referred to as [[Fraunhofer lines]]. In the early years of the modern scientific era, the source of the Sun's energy was a significant puzzle. [[Lord Kelvin]] suggested that the Sun is a gradually cooling liquid body that is radiating an internal store of heat.<ref name=kelvin>
{{Cite journal
|last=Thomson |first=W.
|title=On the Age of the Sun's Heat
|url=http://zapatopi.net/kelvin/papers/on_the_age_of_the_suns_heat.html
|journal=[[Macmillan's Magazine]]
|date=1862
|volume=5 |pages=388–393
|ref=harv
}}</ref> Kelvin and [[Hermann von Helmholtz]] then proposed a [[Kelvin–Helmholtz mechanism|gravitational contraction]] mechanism to explain the energy output, but the resulting age estimate was only 20 million years, well short of the time span of at least 300 million years suggested by some geological discoveries of that time.<ref name=kelvin /><ref>{{cite journal|year=2000|title=Kelvin's age of the Earth paradox revisited|journal=[[Journal of Geophysical Research]]|volume=105|issue=B6|pages=13155–13158|bibcode=2000JGR...10513155S|doi=10.1029/2000JB900028|last1=Stacey|first1=Frank D.}}</ref> In 1890 [[Joseph Norman Lockyer|Joseph Lockyer]], who discovered helium in the solar spectrum, proposed a meteoritic hypothesis for the formation and evolution of the Sun.<ref>
{{Cite book
|last=Lockyer |first=J.N.
|title=The meteoritic hypothesis; a statement of the results of a spectroscopic inquiry into the origin of cosmical systems
|publisher=[[Macmillan and Co.|Macmillan and Co]]
|date=1890
|bibcode=1890mhsr.book.....L
}}</ref>

Not until 1904 was a documented solution offered. [[Ernest Rutherford]] suggested that the Sun's output could be maintained by an internal source of heat, and suggested [[radioactive decay]] as the source.<ref>
{{cite web
|last=Darden |first=L.
|title=The Nature of Scientific Inquiry
|url=http://www.philosophy.umd.edu/Faculty/LDarden/sciinq/
|date=1998
}}</ref> However, it would be [[Albert Einstein]] who would provide the essential clue to the source of the Sun's energy output with his [[mass-energy equivalence]] relation {{nowrap|''E'' {{=}} ''mc''2}}.<ref>{{Cite book|last = Hawking |first = S. W. |author-link = Stephen Hawking |date = 2001 |title = The Universe in a Nutshell |publisher = Bantam Books |isbn = 0-553-80202-X}}</ref> In 1920, Sir [[Arthur Eddington]] proposed that the pressures and temperatures at the core of the Sun could produce a nuclear fusion reaction that merged hydrogen (protons) into helium nuclei, resulting in a production of energy from the net change in mass.<ref>
{{cite web
|title=Studying the stars, testing relativity: Sir Arthur Eddington
|url=http://www.esa.int/esaSC/SEMDYPXO4HD_index_0.html
|work=Space Science
|publisher=[[European Space Agency]]
|date=2005
|accessdate=1 August 2007
}}</ref> The preponderance of hydrogen in the Sun was confirmed in 1925 by [[Cecilia Payne-Gaposchkin|Cecilia Payne]] using the [[ionization]] theory developed by [[Meghnad Saha]], an Indian physicist. The theoretical concept of fusion was developed in the 1930s by the astrophysicists [[Subrahmanyan Chandrasekhar]] and [[Hans Bethe]]. Hans Bethe calculated the details of the two main energy-producing nuclear reactions that power the Sun.<ref name="Bethe">
{{Cite journal
|last=Bethe |first=H.
|title=On the Formation of Deuterons by Proton Combination
|journal=[[Physical Review]]
|volume=54 |issue=10 |pages=862–862
|date=1938
|doi=10.1103/PhysRev.54.862.2
|last2=Critchfield
|first2=C.
|ref=harv
|bibcode = 1938PhRv...54Q.862B }}</ref><ref name="Bethe2">
{{Cite journal
|last=Bethe |first=H.
|title=Energy Production in Stars
|journal=[[Physical Review]]
|volume=55 |issue=1 |pages=434–456
|date=1939
|doi=10.1103/PhysRev.55.434
|ref=harv
|bibcode=1939PhRv...55..434B
}}</ref> In 1957, [[Margaret Burbidge]], [[Geoffrey Burbidge]], [[William Alfred Fowler|William Fowler]] and [[Fred Hoyle]] showed that most of the elements in the universe have been [[nucleosynthesis|synthesized]] by nuclear reactions inside stars, some like the Sun.<ref>
{{Cite journal
|first=E.M. |last=Burbidge
|first2=G.R. |last2=Burbidge
|first3=W.A. |last3=Fowler
|first4=F. |last4=Hoyle
|title=Synthesis of the Elements in Stars
|journal=[[Reviews of Modern Physics]]
|volume=29 |issue=4 |pages=547–650
|date=1957
|doi=10.1103/RevModPhys.29.547
|bibcode=1957RvMP...29..547B
|ref=harv
}}</ref>

===Solar space missions===
{{see also|Solar observatory}}
[[File:Sunspots and Solar Flares.jpg|thumb|The Sun giving out a large [[geomagnetic storm]] on 1:29 pm, EST, 13 March 2012]]
[[File:Moon transit of sun large.ogv|thumb|left|A lunar transit of the Sun captured during calibration of STEREO B's ultraviolet imaging cameras<ref>{{cite web
|last=Phillips
|first=T.
|title=Stereo Eclipse
|url=https://science.nasa.gov/headlines/y2007/12mar_stereoeclipse.htm
|work=Science@NASA
|publisher=[[NASA]]
|date=2007
|accessdate=19 June 2008
|deadurl=yes
|archiveurl=https://web.archive.org/web/20080610082213/https://science.nasa.gov/headlines/y2007/12mar_stereoeclipse.htm
|archivedate=10 June 2008
|df=
}}</ref>]]
The first satellites designed to observe the Sun were [[NASA]]'s [[Pioneer program|Pioneers]] 5, 6, 7, 8 and 9, which were launched between 1959 and 1968. These probes orbited the Sun at a distance similar to that of Earth, and made the first detailed measurements of the solar wind and the solar magnetic field. [[Pioneer 9]] operated for a particularly long time, transmitting data until May 1983.<ref>{{cite web
|last=Wade |first=M.
|title=Pioneer 6-7-8-9-E
|url=http://www.astronautix.com/craft/pio6789e.htm
|date=2008
|publisher=[[Encyclopedia Astronautica]]
|accessdate=22 March 2006
}}</ref><ref>{{cite web
|title=Solar System Exploration: Missions: By Target: Our Solar System: Past: Pioneer 9
|url=http://solarsystem.nasa.gov/missions/profile.cfm?MCode=Pioneer_09
|publisher=[[NASA]]
|accessdate=30 October 2010
|quote=NASA maintained contact with Pioneer 9 until May 1983
}}</ref>

In the 1970s, two [[Helios probes|Helios]] spacecraft and the [[Skylab]] [[Apollo Telescope Mount]] provided scientists with significant new data on solar wind and the solar corona. The Helios 1 and 2 probes were U.S.–German collaborations that studied the solar wind from an orbit carrying the spacecraft inside [[Mercury (planet)|Mercury]]'s orbit at [[perihelion]].<ref name=Burlaga2001/> The Skylab space station, launched by NASA in 1973, included a solar [[observatory]] module called the Apollo Telescope Mount that was operated by astronauts resident on the station.<ref name=Dwivedi2006/> Skylab made the first time-resolved observations of the solar transition region and of ultraviolet emissions from the solar corona.<ref name=Dwivedi2006/> Discoveries included the first observations of [[coronal mass ejection]]s, then called "coronal transients", and of [[coronal hole]]s, now known to be intimately associated with the [[solar wind]].<ref name=Burlaga2001>{{Cite journal|last=Burlaga|first=L.F.|title=Magnetic Fields and plasmas in the inner heliosphere: Helios results|date=2001|journal=Planetary and Space Science|volume=49|issue=14–15|pages=1619–27|doi=10.1016/S0032-0633(01)00098-8|ref=harv|bibcode=2001P&SS...49.1619B}}</ref>

In 1980, the [[Solar Maximum Mission]] was launched by [[NASA]]. This spacecraft was designed to observe [[gamma ray]]s, [[X-ray]]s and [[Ultraviolet|UV]] radiation from [[solar flare]]s during a time of high solar activity and [[Sun#External links|solar luminosity]]. Just a few months after launch, however, an electronics failure caused the probe to go into standby mode, and it spent the next three years in this inactive state. In 1984 [[Space Shuttle Challenger|Space Shuttle ''Challenger'']] mission [[STS-41C]] retrieved the satellite and repaired its electronics before re-releasing it into orbit. The Solar Maximum Mission subsequently acquired thousands of images of the solar corona before [[Atmospheric reentry|re-entering]] Earth's atmosphere in June 1989.<ref>
{{cite web |last=Burkepile |first=C.J.
|title=Solar Maximum Mission Overview
|url=http://web.hao.ucar.edu/public/research/svosa/smm/smm_mission.html
|date=1998
|accessdate=22 March 2006
| archiveurl = https://web.archive.org/web/20060405183758/http://web.hao.ucar.edu/public/research/svosa/smm/smm_mission.html| archivedate = 5 April 2006}}</ref>

Launched in 1991, Japan's [[Yohkoh]] (''Sunbeam'') satellite observed solar flares at X-ray wavelengths. Mission data allowed scientists to identify several different types of flares, and demonstrated that the corona away from regions of peak activity was much more dynamic and active than had previously been supposed. Yohkoh observed an entire solar cycle but went into standby mode when an [[solar eclipse|annular eclipse]] in 2001 caused it to lose its lock on the Sun. It was destroyed by atmospheric re-entry in 2005.<ref>
{{cite press
|title=Result of Re-entry of the Solar X-ray Observatory "Yohkoh" (SOLAR-A) to the Earth's Atmosphere
|url=http://www.jaxa.jp/press/2005/09/20050913_yohkoh_e.html
|publisher=[[Japan Aerospace Exploration Agency]]
|date=2005
|accessdate=22 March 2006
}}</ref>

One of the most important solar missions to date has been the [[Solar and Heliospheric Observatory]], jointly built by the [[European Space Agency]] and [[NASA]] and launched on 2 December 1995.<ref name=Dwivedi2006/> Originally intended to serve a two-year mission, a mission extension through 2012 was approved in October 2009.<ref name=sohoext>{{cite web| date = 7 October 2009|url = http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=45685|title = Mission extensions approved for science missions|work = ESA Science and Technology|accessdate = 16 February 2010}}</ref> It has proven so useful that a follow-on mission, the [[Solar Dynamics Observatory]] (SDO), was launched in February 2010.<ref name=sdolaunch>{{cite web| date = 11 February 2010|url = http://www.nasa.gov/home/hqnews/2010/feb/HQ_10-040_SDO_launch.html|title = NASA Successfully Launches a New Eye on the Sun|work = NASA Press Release Archives|accessdate = 16 February 2010}}</ref> Situated at the [[Lagrangian point]] between Earth and the Sun (at which the gravitational pull from both is equal), SOHO has provided a constant view of the Sun at many wavelengths since its launch.<ref name=Dwivedi2006/> Besides its direct solar observation, SOHO has enabled the discovery of a large number of [[comet]]s, mostly tiny [[sungrazing comet]]s that incinerate as they pass the Sun.<ref>
{{cite web
|title=Sungrazing Comets
|url=http://sungrazer.nrl.navy.mil/
|publisher=[[Large Angle and Spectrometric Coronagraph|LASCO]] ([[US Naval Research Laboratory]])
|accessdate=19 March 2009
}}</ref>
[[File:Giant prominence on the sun erupted.jpg|thumb|300px|A solar prominence erupts in August 2012, as captured by SDO]]

All these satellites have observed the Sun from the plane of the ecliptic, and so have only observed its equatorial regions in detail. The [[Ulysses probe]] was launched in 1990 to study the Sun's polar regions. It first travelled to [[Jupiter]], to "slingshot" into an orbit that would take it far above the plane of the ecliptic. Once Ulysses was in its scheduled orbit, it began observing the solar wind and magnetic field strength at high solar latitudes, finding that the solar wind from high latitudes was moving at about 750 km/s, which was slower than expected, and that there were large magnetic waves emerging from high latitudes that scattered galactic [[cosmic ray]]s.<ref>
{{cite web
|author=[[Jet Propulsion Laboratory|JPL]]/[[California Institute of Technology|CALTECH]]
|title=Ulysses: Primary Mission Results
|url=http://ulysses.jpl.nasa.gov/science/mission_primary.html
|publisher=[[NASA]]
|date=2005
|accessdate=22 March 2006
|deadurl=yes
|archiveurl=https://web.archive.org/web/20060106150819/http://ulysses.jpl.nasa.gov/science/mission_primary.html
|archivedate=6 January 2006
|df=
}}</ref>

Elemental abundances in the photosphere are well known from [[astronomical spectroscopy|spectroscopic]] studies, but the composition of the interior of the Sun is more poorly understood. A [[solar wind]] sample return mission, [[Genesis (spacecraft)|Genesis]], was designed to allow astronomers to directly measure the composition of solar material.<ref>
{{Cite journal
|last=Calaway |first=M.J.
|title=Genesis capturing the Sun: Solar wind irradiation at Lagrange 1
|journal=[[Nuclear Instruments and Methods in Physics Research B]]
|volume=267 |issue=7 |pages=1101–1108
|date=2009
|doi=10.1016/j.nimb.2009.01.132
|last2=Stansbery
|first2=Eileen K.
|last3=Keller
|first3=Lindsay P.
|ref=harv
|bibcode = 2009NIMPB.267.1101C }}</ref>

The [[STEREO|Solar Terrestrial Relations Observatory]] (STEREO) mission was launched in October 2006. Two identical spacecraft were launched into orbits that cause them to (respectively) pull further ahead of and fall gradually behind Earth. This enables [[stereoscopic]] imaging of the Sun and solar phenomena, such as [[coronal mass ejections]].<ref name=inst>{{cite web| date = 8 March 2006|url = http://www.nasa.gov/mission_pages/stereo/spacecraft/index.html|title = STEREO Spacecraft & Instruments|work = NASA Missions|accessdate = 30 May 2006}}</ref><ref>{{Cite journal| title= Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI)|last = Howard | first = R. A.|last2 = Moses | first2 = J. D.| last3 = Socker | first3 = D. G.| last4 = Dere | first4 = K. P.| last5 = Cook | first5 = J. W.|journal=Advances in Space Research|volume= 29|issue= 12|pages=2017–2026|date= 2002| ref= harv |bibcode=2008SSRv..136...67H |doi=10.1007/s11214-008-9341-4
}}</ref>

The [[Indian Space Research Organisation]] has scheduled the launch of a 100 kg satellite named [[Aditya (spacecraft)|Aditya]] for 2017–18. Its main instrument will be a [[coronagraph]] for studying the dynamics of the Solar corona.<ref>{{cite web |url= http://timesofindia.indiatimes.com/india/Aditya-1-launch-delayed-to-2015-16/articleshow/16326842.cms|title= Aditya 1 launch delayed to 2015–16| first = Srinivas | last = Laxman| last2 = Rhik Kundu | first2 = TNN |date=9 September 2012|work= [[The Times of India]]|publisher= [[Bennett, Coleman & Co. Ltd.]]}}</ref>

==Observation and effects==
[[File:Anatomy of a Sunset-2.jpg|thumb|right|300px|During certain atmospheric conditions, the Sun becomes clearly visible to the naked eye, and can be observed without stress to the eyes. Click on this photo to see the full cycle of a [[sunset]], as observed from the high plains of the [[Mojave Desert]].]]
[[File:STS-134 EVA4 view to the Russian Orbital Segment.jpg|thumb|right|The Sun, as seen from low Earth orbit overlooking the [[International Space Station]]. This sunlight is not filtered by the lower atmosphere, which blocks much of the solar spectrum]]
The brightness of the Sun can cause pain from looking at it with the [[naked eye]]; however, doing so for brief periods is not hazardous for normal non-dilated eyes.<ref>

{{Cite journal
|first=T.J. |last=White |first2=M.A. |last2=Mainster |first3=P.W. |last3=Wilson
|first4=J.H. |last4=Tips
|title=Chorioretinal temperature increases from solar observation
|journal=[[Bulletin of Mathematical Biophysics]]
|volume=33 |issue=1 |pages=1–17
|date=1971
|doi=10.1007/BF02476660
|ref=harv
}}</ref><ref>
{{Cite journal
|first=M.O.M. |last=Tso |first2=F.G. |last2=La Piana
|title=The Human Fovea After Sungazing
|journal=[[Transactions of the American Academy of Ophthalmology and Otolaryngology]]
|date=1975
|volume=79 |pages=OP788–95
|pmid=1209815
|issue=6
|ref=harv
}}</ref> Looking directly at the Sun causes [[phosphene]] visual artifacts and temporary partial blindness. It also delivers about 4 milliwatts of sunlight to the retina, slightly heating it and potentially causing damage in eyes that cannot respond properly to the brightness.<ref>
{{Cite journal
|last=Hope-Ross |first=M.W.
|title=Ultrastructural findings in solar retinopathy
|journal=[[Eye (journal)|Eye]]
|volume=7
|issue=4 |date=1993
|doi=10.1038/eye.1993.7
|pmid=8325420
|last2=Mahon
|first2=GJ
|last3=Gardiner
|first3=TA
|last4=Archer
|first4=DB
|ref=harv
|pages=29–33
}}</ref><ref>
{{Cite journal
|title=Solar Retinopathy from Sun-Gazing Under Influence of LSD
|last=Schatz |first=H. |last2=Mendelblatt |first2=F.
|journal=[[British Journal of Ophthalmology]]
|volume=57 |issue=4 |date=1973
|doi=10.1136/bjo.57.4.270
|pmid=4707624
|ref=harv |pmc=1214879
|pages=270–3
}}</ref> [[ultraviolet|UV]] exposure gradually yellows the lens of the eye over a period of years, and is thought to contribute to the formation of [[cataracts]], but this depends on general exposure to solar UV, and not whether one looks directly at the Sun.<ref>
{{cite web
|last=Chou |first=B.R.
|title=Eye Safety During Solar Eclipses
|url=http://eclipse.gsfc.nasa.gov/SEhelp/safety2.html
|date=2005
}} "''While environmental exposure to UV radiation is known to contribute to the accelerated aging of the outer layers of the eye and the development of cataracts, the concern over improper viewing of the Sun during an eclipse is for the development of "eclipse blindness" or retinal burns.''"</ref> Long-duration viewing of the direct Sun with the naked eye can begin to cause UV-induced, sunburn-like lesions on the retina after about 100 seconds, particularly under conditions where the UV light from the Sun is intense and well focused;<ref>
{{Cite journal
|first=W.T. Jr. |last=Ham |first2=H.A. |last2=Mueller |first3=D.H. |last3=Sliney
|journal=[[Nature (journal)|Nature]]
|title=Retinal sensitivity to damage from short wavelength light
|volume=260
|issue=5547 |pages=153–155
|date=1976
|doi=10.1038/260153a0
|ref=harv
|bibcode = 1976Natur.260..153H }}</ref><ref>
{{Cite book
|first=W.T. Jr. |last=Ham |first2=H.A. |last2=Mueller |first3=J.J. Jr. |last3=Ruffolo
|first4=D. III|last4=Guerry
|chapter=Solar Retinopathy as a function of Wavelength: its Significance for Protective Eyewear
|title=The Effects of Constant Light on Visual Processes
|editor=Williams, T.P.
|editor2=Baker, B.N.
|publisher=[[Plenum Press]]
|pages=319–346
|date=1980
|isbn=0-306-40328-5
}}</ref> conditions are worsened by young eyes or new lens implants (which admit more UV than aging natural eyes), Sun angles near the zenith, and observing locations at high altitude.

Viewing the Sun through light-concentrating [[optics]] such as [[binoculars]] may result in permanent damage to the retina without an appropriate filter that blocks UV and substantially dims the sunlight. When using an attenuating filter to view the Sun, the viewer is cautioned to use a filter specifically designed for that use. Some improvised filters that pass UV or [[infrared|IR]] rays, can actually harm the eye at high brightness levels.<ref>
{{Cite book
|first=T. |last=Kardos
|title=Earth science
|url=https://books.google.com/?id=xI6EDV_PRr4C&pg=PT102
|page=87
|publisher= [[J.W. Walch]]
|date=2003
|isbn=978-0-8251-4500-1
}}</ref>
[[Herschel wedge]]s, also called Solar Diagonals, are effective and inexpensive for small telescopes. The sunlight that is destined for the eyepiece is reflected from an unsilvered surface of a piece of glass. Only a very small fraction of the incident light is reflected. The rest passes through the glass and leaves the instrument. If the glass breaks because of the heat, no light at all is reflected, making the device fail-safe. Simple filters made of darkened glass allow the full intensity of sunlight to pass through if they break, endangering the observer's eyesight. Unfiltered binoculars can deliver hundreds of times as much energy as using the naked eye, possibly causing immediate damage. It is claimed that even brief glances at the midday Sun through an unfiltered telescope can cause permanent damage.<ref name=Macdonald>{{cite book|last=Macdonald|first=Lee|date=2012|title=How to Observe the Sun Safely|publisher=Springer Science + Business Media|place=New York|chapter=2. Equipment for Observing the Sun|page=17|doi=10.1007/978-1-4614-3825-0_2|quote=NEVER LOOK DIRECTLY AT THE SUN THROUGH ANY FORM OF OPTICAL EQUIPMENT, EVEN FOR AN INSTANT. A brief glimpse of the Sun through a telescope is enough to cause permanent eye damage, or even blindness. Even looking at the Sun with the naked eye for more than a second or two is not safe. Do not assume that it is safe to look at the Sun through a filter, no matter how dark the filter appears to be.}}</ref>


[[File:Doppelsonne Halo Echzell Hessen 12-08-2012.jpg|thumb|left|[[Halo (optical phenomenon)|Halo]] with [[sun dog]]s]]
Partial [[solar eclipse]]s are hazardous to view because the eye's [[pupil]] is not adapted to the unusually high visual contrast: the pupil dilates according to the total amount of light in the field of view, ''not'' by the brightest object in the field. During partial eclipses most sunlight is blocked by the [[Moon]] passing in front of the Sun, but the uncovered parts of the photosphere have the same [[surface brightness]] as during a normal day. In the overall gloom, the pupil expands from ~2 mm to ~6 mm, and each retinal cell exposed to the solar image receives up to ten times more light than it would looking at the non-eclipsed Sun. This can damage or kill those cells, resulting in small permanent blind spots for the viewer.<ref name="Espenak">
{{cite web
|last=Espenak |first=Fred
|title=Eye Safety During Solar Eclipses
|url=http://eclipse.gsfc.nasa.gov/SEhelp/safety.html
|publisher=[[NASA]]
|date=26 April 1996
}}</ref> The hazard is insidious for inexperienced observers and for children, because there is no perception of pain: it is not immediately obvious that one's vision is being destroyed.

[[File:Actual Sunrise.jpeg|300px|thumb|right|A sunrise]]

During [[sunrise]] and [[sunset]], sunlight is attenuated because of [[Rayleigh scattering]] and [[Mie theory|Mie scattering]] from a particularly long passage through Earth's atmosphere,<ref name=Haber2005>{{Cite journal|last=Haber|first=Jorg| last2 = Magnor | first2 = Marcus| last3 = Seidel | first3 = Hans-Peter|title=Physically based Simulation of Twilight Phenomena|date=2005|journal=ACM Transactions on Graphics|volume=24|issue=4|pages=1353–1373|doi=10.1145/1095878.1095884|citeseerx = 10.1.1.67.2567|ref=harv}}</ref> and the Sun is sometimes faint enough to be viewed comfortably with the naked eye or safely with optics (provided there is no risk of bright sunlight suddenly appearing through a break between clouds). Hazy conditions, atmospheric dust, and high humidity contribute to this atmospheric attenuation.<ref>{{Cite journal|title=Diurnal asymmetries in global radiation| first = I. G. | last = Piggin|journal=Springer|date=1972|volume=20|issue=1|doi=10.1007/BF02243313|pages=41–48|ref=harv|bibcode = 1972AMGBB..20...41P }}</ref>

An [[optical phenomenon]], known as a [[green flash]], can sometimes be seen shortly after sunset or before sunrise. The flash is caused by light from the Sun just below the horizon being [[refraction|bent]] (usually through a [[temperature inversion]]) towards the observer. Light of shorter wavelengths (violet, blue, green) is bent more than that of longer wavelengths (yellow, orange, red) but the violet and blue light is [[Rayleigh scattering|scattered]] more, leaving light that is perceived as green.<ref>
{{cite web
|title=The Green Flash
|url=http://www.bbc.co.uk/weather/features/understanding/greenflash.shtml
|publisher=BBC
|accessdate=10 August 2008
|archiveurl=https://web.archive.org/web/20081216135504/http://www.bbc.co.uk/weather/features/understanding/greenflash.shtml
|archivedate=16 December 2008
}}</ref>

[[Ultraviolet]] light from the Sun has [[antiseptic]] properties and can be used to sanitize tools and water. It also causes [[sunburn]], and has other biological effects such as the production of [[vitamin D]] and [[sun tanning]]. Ultraviolet light is strongly attenuated by Earth's [[ozone layer]], so that the amount of UV varies greatly with [[latitude]] and has been partially responsible for many biological adaptations, including variations in [[human skin color]] in different regions of the globe.<ref>
{{Cite journal
|last=Barsh |first=G.S.
|title=What Controls Variation in Human Skin Color?
|journal=[[PLoS Biology]]
|volume=1
|issue=1 |page=e7
|date=2003
|pmid=14551921
|pmc=212702
|doi=10.1371/journal.pbio.0000027
|ref=harv
}}</ref>

==Planetary system==

{{main article |Solar System}}

The Sun has eight known planets. This includes four [[terrestrial planets]] ([[Mercury (planet)|Mercury]], [[Venus]], [[Earth]], and [[Mars]]), two [[gas giants]] ([[Jupiter]] and [[Saturn]]), and two [[ice giants]] ([[Uranus]] and [[Neptune]]). The Solar System also has at least five [[dwarf planets]], an [[asteroid belt]], numerous [[comets]], and a large number of icy bodies which lie beyond the orbit of Neptune.

==See also==
{{Wikipedia books |1=The Sun}}
{{cmn|30em|
* [[Advanced Composition Explorer]]
* [[Antisolar point]]
* [[List of brightest stars]]
* [[Solar energy]]
* [[Sun dogs]]
* [[Sun path]]
* [[Sun-Earth Day]]
* [[Sunday]]
* [[Sungazing]]
* [[Timeline of the far future]]
}}
{{Portal bar|Star|Solar System}}

==Notes==
{{notes
| notes =
{{efn
| name = heavy elements
| In [[astronomy|astronomical sciences]], the term ''heavy elements'' (or ''metals'') refers to all [[chemical element|elements]] except hydrogen and helium.
}}
{{efn
| name = power production density
| A 50 kg adult human has a volume of about 0.05 m3, which corresponds to 13.8 watts, at the volumetric power of the solar center. This is 285 kcal/day, about 10% of the actual average caloric intake and output for humans in non-stressful conditions.
}}
{{efn
| name = particle density
| Earth's atmosphere near sea level has a particle density of about 2{{e|25}} m−3.
}}
}}

==References==
{{reflist|30em}}

==Further reading==
* {{Cite book|last=Cohen |first=Richard |date=2010 |title=Chasing the Sun: the Epic Story of the Star that Gives us Life |publisher=[[Simon & Schuster]]|isbn=1-4000-6875-4}}
* {{Cite journal|last=Thompson |first=M. J. |date=2004 |title=Solar interior: Helioseismology and the Sun's interior |journal=[[Astronomy & Geophysics]] |volume=45 |issue=4 |pages=21–25 }}
* [http://www.scholarpedia.org/article/Solar_activity Solar Activity] [[Scholarpedia]] Hugh Hudson 3(3):3967. {{doi|10.4249/scholarpedia.3967}}

==External links==
{{Sister project links|Sun}}
* [http://sohowww.nascom.nasa.gov/ Nasa SOHO (Solar & Heliospheric Observatory) satellite]
* [http://www.nso.edu/ National Solar Observatory]
* [http://www.astronomycast.com/astronomy/episode-30-the-sun-spots-and-all/ Astronomy Cast: The Sun]
* [http://www.boston.com/bigpicture/2008/10/the_sun.html A collection of spectacular images of the Sun from various institutions] (''[[The Boston Globe]]'')
* [http://www.acrim.com/ Satellite observations of solar luminosity]
* [http://www.suntrek.org/ Sun|Trek, an educational website about the Sun]
* [https://web.archive.org/web/20050518081349/http://www.solarphysics.kva.se/ The Swedish 1-meter Solar Telescope, SST]
* [http://alienworlds.glam.ac.uk/sunStructure.html An animated explanation of the structure of the Sun] (University of Glamorgan)
* [https://www.youtube.com/watch?v=qpMRtvFD8ek&hl=fr Animation – The Future of the Sun]
* [https://web.archive.org/web/20100315111135/https://science.nasa.gov/headlines/y2010/12mar_conveyorbelt.htm Solar Conveyor Belt Speeds Up] – NASA – images, link to report on Science
* [https://www.youtube.com/watch?v=w-41gAPmUG0&feature=youtube_gdata&ab_channel=NASAGoddard NASA 5-year timelapse video of the Sun]
* [https://www.youtube.com/watch?v=6tmbeLTHC_0&ab_channel=NASAGoddard Sun in Ultra High Definition] NASA 11/1/2015

{{The Sun|state=uncollapsed}}
{{Sun spacecraft}}
{{Solar System}}
{{Nearest star systems|1}}
{{Astronomy navbar}}

{{Authority control}}

[[Category:G-type main-sequence stars]]
[[Category:Light sources]]
[[Category:Plasma physics]]
[[Category:Space plasmas]]
[[Category:Stars with proper names]]
[[Category:Sun| ]]
[[Category:Astronomical objects known since antiquity]]
[[Category:Articles containing video clips]]

Gravel Pit

2017-08-09T21:21:10Z

81.147.69.112:

{{NewInfobox Map
|name=
|image=
|caption=

|maptype=ad
|filename=cp_gravelpit
|version=Official Release
|author1=valve
|author1steam=
|author2=
|author2steam=
|author3=
|author3steam=
|released=9 October 2007
|updated=9 October 2007
|official=1

|gamemode1=6v6
|gamemode2=hl
|gamemode3=
|adapted=
|pro=
|popularity=obsolete
|lpleague=etf2lhl
|lpseason=9

|download=http://fakkelbrigade.eu/maps/cp_gravelpit.bsp
|workshop=
|tf2maps=
|gamebanana=
|tftv=
|tftv2=
|etf2l=
|ugc=
|officialwiki=Gravel_Pit
|officialwiki2=Gravel_Pit_(competitive)

|footnotes=
}}
{{other uses}}
{{Use dmy dates|date=December 2013}}
[[File:Gravel on a beach in Thirasia, Santorini, Greece.jpg|thumb|right|250px|Gravel (largest fragment in this photo is about 4 cm)]]
[[File:Gravel1.jpg|thumb|right|250px|A [[gravel road]] in [[Terre Haute, Indiana]]]]
[[File:gravel small.jpg|right|frame|Gravel being unloaded from a [[barge]]]]

'''Gravel''' {{IPAc-en|ˈ|ɡ|r|æ|v|əl}} is a loose aggregation of rock fragments. Gravel is classified by [[Particle size (grain size)|particle size]] range and includes size classes from [[Granule_(geology)|granule]]- to [[boulder]]-sized fragments. In the [[Udden-Wentworth scale]] gravel is categorized into granular gravel ({{convert|2|to|4|mm|in|abbr=on|disp=or}}) and [[pebble]] gravel ({{convert|4|to|64|mm|in|1|abbr=on|disp=or}}). One cubic metre of gravel typically weighs about 1,800 kg (or a cubic yard weighs about 3,000 pounds).

Gravel is an important commercial product, with a number of applications. Many [[road]]ways are [[pavement (roads)|surfaced]] with gravel, especially in [[rural]] areas where there is little [[traffic]]. Globally, far more roads are surfaced with gravel than with [[concrete]] or [[tarmac]]; [[Russia]] alone has over {{convert|400000|km|mi|abbr=on}} of [[gravel road]]s.<ref>{{cite web|title=1 KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY|url=http://ir.knust.edu.gh/bitstream/123456789/5763/1/BENJAMIN%20GBEVE.pdf|website=1 KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY}}</ref> Both [[sand]] and small gravel are also important for the manufacture of [[concrete]].

==Geological formation==
Large gravel deposits are a common geological feature, being formed as a result of the [[weathering]] and [[erosion]] of rocks. The action of rivers and waves tends to pile up gravel in large accumulations. This can sometimes result in gravel becoming compacted and concreted into the [[sedimentary rock]] called [[Conglomerate (geology)|conglomerate]]. Where natural gravel deposits are insufficient for human purposes, gravel is often produced by quarrying and crushing hard-wearing rocks, such as sandstone, limestone, or basalt. Quarries where gravel is extracted are known as gravel pits. Southern England possesses particularly large concentrations of them due to the widespread deposition of gravel in the region during the [[Ice Age]]s.

===Modern production===
As of 2006, the United States is the world's leading producer and consumer of gravel.<ref>[http://minerals.usgs.gov/minerals/pubs/mcs/2006/mcs2006.pdf Mineral Commodity Summaries 2006] 2009</ref><ref>[http://www.indexmundi.com/en/commodities/minerals/silica/silica_t11.html Industrial Sand And Gravel (Silica): World Production, By Country] 2009</ref>

==Etymology==
The word ''gravel'' comes from the [[Breton language]]. In Breton, "grav" means coast. Adding the "-el" suffix in Breton denotes the component parts of something larger. Thus "gravel" means the small stones which make up such a beach on the coast. Many dictionaries ignore the Breton language, citing [[Old French]] ''gravele''<ref>Collins English Dictionary – Complete & Unabridged 11th Edition. Retrieved 30 August 2012 from CollinsDictionary.com website:http://www.collinsdictionary.com/dictionary/english/gravel</ref> or ''gravelle''.<ref>Gravel, n., ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) © Oxford University Press 2009</ref>

Gravel often has the meaning a mixture of different size pieces of stone mixed with sand and possibly some clay. In American English, small stones without sand mixed in are known as [[crushed stone]].<ref>"gravel." Noah Webster's 1828 American Dictionary of the English Language. 2015. http://1828.mshaffer.com/d/word/gravel (8 January 2015)</ref><ref>"Gravel, n." def. 1. Whitney, William Dwight. The Century Dictionary; an Encyclopedic Lexicon of the English Language,. Vol. 3. New York: Century, 1889. 2607. Print.</ref>

==Types==
[[File:Gravel small stones.jpg|thumb|250px|Gravel with stones sized roughly between 5 and 15 mm]]
[[File:Kiesgrube Bernau 2012 - panoramio (7).jpg|thumb|250px|Sand and gravel separator in a gravel pit in [[Brandenburg]] (eastern Germany)]]
Types of gravel include:

* '''Bank gravel''': naturally deposited gravel intermixed with sand or [[clay]] found in and next to rivers and streams. Also known as "bank run" or "river run".
* '''Bench gravel''': a bed of gravel located on the side of a valley above the present stream bottom, indicating the former location of the stream bed when it was at a higher level.
*'''Creek rock or river rock''': this is generally rounded, semi-polished stones, potentially of a wide range of types, that are dredged or scooped from [[stream bed]]s. It is also often used as concrete aggregate and less often as a paving surface.
*'''Crushed stone''': rock crushed and graded by screens and then mixed to a blend of stones and fines. It is widely used as a surfacing for roads and driveways, sometimes with [[tar]] applied over it. Crushed stone may be made from [[granite]], [[limestone]], [[dolostone]], and other rocks. Also known as "crusher run", DGA (dense grade aggregate) QP (quarry process), and shoulder stone.<ref>{{cite web|url=http://www.braenstone.com/crushed-stone/quarry-process-qp-dga/|title=Quarry Process - QP, DGA - NJ, NY, NYC, PA|website=www.braenstone.com}}</ref>
* '''Fine gravel''': gravel consisting of particles with a diameter of 2 to 4 mm.
* '''Lag gravel''': a surface accumulation of coarse gravel produced by the removal of finer particles.
* '''Pay gravel''': also known as "pay dirt"; a nickname for gravel with a high concentration of gold and other precious metals. The metals are recovered through [[gold panning]].
* '''Pea gravel''': gravel that consists of small, rounded stones used in concrete surfaces. Also used for walkways, driveways and as a substrate in home aquariums.
* '''Piedmont gravel''': a coarse gravel carried down from high places by mountain streams and deposited on relatively flat ground, where the water runs more slowly.
* '''Plateau gravel''': a layer of gravel on a plateau or other region above the height at which stream-terrace gravel is usually found.

==Relationship to plant life==
In locales where gravelly soil is predominant, plant life is generally more sparse.<ref>C.Michael Hogan. 2010. [http://www.eoearth.org/article/Abiotic_factor?topic=49461 ''Abiotic factor''. Encyclopedia of Earth. eds Emily Monosson and C. Cleveland. National Council for Science and the Environment] {{webarchive|url=https://web.archive.org/web/20130608071757/http://www.eoearth.org/article/Abiotic_factor?topic=49461 |date=8 June 2013 }}. Washington DC</ref> This outcome derives from the inferior ability of gravels to retain moisture, as well as the corresponding paucity of mineral nutrients, since finer soils that contain such minerals are present in smaller amounts.

==See also==
* [[Construction aggregate]]
* [[Pebble]]
* [[Rock (geology)|Rock]]

==References==
{{reflist|30em}}

==External links==
{{Commonscat-inline|Gravel}}

{{Geotechnical engineering|state=collapsed}}

[[Category:Sedimentology]]
[[Category:Building stone]]
[[Category:Natural materials]]
[[Category:Pavements]]
[[Category:Gardening aids]]
[[Category:Stone]]
[[Category:Soil-based building materials]]

== Usage in competitive ==
{{Gravel Pit/MapLeagueInclusionTable}}
== Locations ==
=== Point A ===
{{Map locations
| title = Gravel Pit — Point A
| image = Gravelpit Point A.jpg
| area1 = A-B connector | x1=186px | y1=61px
| area2 = Left | x2=149px | y2=164px
| area3 = Right | x3=650px | y3=161px
| area4 = A-C connector | x4=37px | y4=94px
| area5 = Window | x5=493px | y5=258px
}}

=== Point B ===
{{Map locations
| title = Gravel Pit — Point B
| image = Gravelpit Point B.jpg
| area1 = C-B left connector | x1=392px | y1=52px
| area2 = C-B right connector / Fence | x2=582px | y2=72px
| area3 = A-B connector | x3=220px | y3=95px
| area4 = Shed | x4=281px | y4=118px
| area5 = Short | x5=169px | y5=112px
| area6 = Shadow side | x6=571px | y6=209px
| area7 = Rampside | x7=446px | y7=261px
| area8 = Long | x8=135px | y8=294px
| area9 = Rock | x9=441px | y9=346px
}}

=== Point C ===
{{Map locations
| title = Gravel Pit — Point C
| image = Gravelpit Point C.jpg
| area1 = Tower | x1=429px | y1=34px
| area2 = 3 / Main | x2=326px | y2=85px
| area3 = 4 | x3=508px | y3=124px
| area4 = 2 / Tires | x4=235px | y4=164px
| area5 = 5 | x5=523px | y5=205px
| area6 = 1 | x6=233px | y6=248px
| area7 = Lower | x7=500px | y7=291px
| area8 = Back right ramp | x8=628px | y8=289px
| area9 = Back left ramp | x9=268px | y9=395px
}}

{{All Maps Navbox}}

Coalplant

2017-08-09T21:19:43Z

81.147.69.112:

{{stub}}
{{NewInfobox Map
|name=
|image=
|caption=

|maptype=koth
|filename=koth_coalplant_b7
|version=Beta 7
|author1=Ian "Scorpio Uprising" Cuslidge
|author1steam=76561197977081885
|author2=
|author2steam=
|author3=
|author3steam=
|released=24 June 2013
|updated=15 January 2014
|official=

|gamemode1=6v6
|gamemode2=hl
|gamemode3=
|adapted=Ashville
|pro=
|popularity=moderate
|lpleague=
|lpseason=

|download=http://fakkelbrigade.eu/maps/koth_coalplant_b7.bsp.bz2
|workshop=454125056
|tf2maps=22081
|gamebanana=
|tftv=10687
|tftv2=
|etf2l=
|ugc=
|officialwiki=
|officialwiki2=

|footnotes=
}}

A fossil fuel power station is a power station which burns fossil fuel such as coal, natural gas, or petroleum to produce electricity. Central station fossil fuel power plants are designed on a large scale for continuous operation. In many countries, such plants provide most of the electrical energy used. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator. The prime mover may be a steam turbine, a gas turbine or, in small plants, a reciprocating internal combustion engine. All plants use the energy extracted from expanding gas, either steam or combustion gases. Very few MHD generators have been built which directly convert the energy of hot, moving water into electricity. MHD means Magnetohydrodynamics, which is the study of the magnetic properties of electrically conducting fluids. Examples of such magnetofluids include plasmas, liquid metals, salt water and electrolytes.

By-products of thermal power plant operation must be considered in their design and operation. Waste heat energy, which remains due to the finite efficiency of the Carnot, Rankine, or Diesel power cycle, is released directly to the atmosphere or river/lake water, or indirectly to the atmosphere using a cooling tower with river or lake water used as a cooling medium. The flue gas from combustion of the fossil fuels is discharged to the air. This gas contains carbon dioxide and water vapor, as well as other substances such as nitrogen oxides (NOx), sulfur oxides (SOx), mercury, traces of other metals, and, for coal-fired plants, fly ash. Solid waste ash from coal-fired boilers must also be removed. Some coal ash can be recycled for building materials.[1]

Fossil fueled power stations are major emitters of carbon dioxide (CO2), a greenhouse gas which according to a consensus opinion of scientific organisations is a contributor to global warming. The results of a recent study[2] show that the net income available to shareholders of large companies could see a significant reduction from the greenhouse gas emissions liability related to only natural disasters in the U.S. from a single coal-fired power plant. However, as of 2015, no such cases have awarded damages in the U.S. Per unit of electric energy, brown coal emits nearly two times as much CO2 as natural gas, and black coal emits somewhat less than brown. Carbon capture and storage of emissions is not currently available.

==Basic concepts==
In a fossil fuel power plant the chemical energy stored in fossil fuels such as [[coal]], [[fuel oil]], [[natural gas]] or [[oil shale]] and [[oxygen]] of the [[air]] is converted successively into [[thermal energy]], [[mechanical energy]] and, finally, [[electrical energy]]. Each fossil fuel power plant is a complex, custom-designed system. Construction costs, {{As of|2004|lc=on}}, run to [[United States dollar|US$]]1,300 per [[kilowatt]], or $650 million for a 500 [[MWe]] unit{{Citation needed|date=March 2009}}. Multiple generating units may be built at a single site for more efficient use of [[land use|land]], [[natural resource]]s and [[labor (economics)|labor]]. Most [[thermal power station]]s in the world use fossil fuel, outnumbering [[nuclear power|nuclear]], [[geothermal power|geothermal]], [[biomass]], or [[solar energy|solar thermal]] plants.

===Heat into mechanical energy===
The [[second law of thermodynamics]] states that any [[Thermodynamic cycle|closed-loop cycle]] can only convert a fraction of the heat produced during combustion into [[mechanical work]]. The rest of the heat, called [[waste heat]], must be released into a cooler environment during the return portion of the cycle. The fraction of heat released into a cooler medium must be equal or larger than the ratio of [[absolute temperature]]s of the cooling system (environment) and the heat source (combustion furnace). Raising the furnace temperature improves the efficiency but complicates the design, primarily by the selection of alloys used for construction, making the furnace more expensive. The waste heat cannot be converted into mechanical energy without an even cooler cooling system. However, it may be used in [[cogeneration]] plants to heat buildings, produce hot water, or to heat materials on an industrial scale, such as in some [[oil refinery|oil refineries]], plants, and [[chemical synthesis]] plants.

Typical thermal efficiency for utility-scale electrical generators is around 33% for coal and oil-fired plants, and 56 – 60% (LHV) for [[combined-cycle]] gas-fired plants. Plants designed to achieve peak efficiency while operating at capacity will be less efficient when operating off-design (i.e. temperatures too low.)<ref name="ELECTRIC GENERATION
EFFICIENCY Page 5">{{cite web|url=http://www.npc.org/study_topic_papers/4-dtg-electricefficiency.pdf|title=ELECTRIC GENERATION EFFICIENCY: Working Document of the NPC Global Oil & Gas Study|publisher=Highbeam Research|accessdate=18 July 2007}}</ref>

Practical fossil fuel stations operating as heat engines cannot exceed the [[Carnot cycle]] limit for conversion of heat energy into useful work. [[Fuel cell]]s do not have the same thermodynamic limits as they are not heat engines.

'''Temperature of Hot Steam'''.
Using the reported efficiencies and the efficiency of an ideal [[Carnot engine]] one can estimate the engine temperature. This estimate is the minimum heat water/steam temperature as we neglect other losses. For example, the effective temperature of the cooling water can be significantly higher.
Assume the cold temperature <math> T_c </math> is 10 °C, or 280 K than <math> T_h </math> equals:
: <math> \eta \,=\, 1 - \frac{T_c}{T_h} </math>
: <math> T_h \,=\, \frac{T_c}{1 - \eta} </math>
: <math> T_h \,=\, \frac{280}{1 - 0.33} </math>
: <math> T_h \,=\, 418\, \mathrm{K} = 145^o \mathrm{C} </math>

This temperature is presumably much lower than the actual steam temperature due to several losses.

==Coal==
[[File:Coal fired power plant diagram.svg|thumb|upright=1.3|Diagram of a typical steam-cycle coal power plant (proceeding from left to right)]]
{{main|Thermal power station}}

Coal is the most abundant [[fossil fuel]] on the planet, and widely used as the source of energy in [[thermal power station]]s. It is a relatively cheap fuel, with some of the largest deposits in regions that are stable politically, such as [[China]], [[India]] and the [[United States]]. This contrasts with [[natural gas]], the largest deposits of which are located in Russia, Iran, Qatar, Turkmenistan and the US. Solid coal cannot directly replace natural gas or petroleum in most applications, petroleum is mostly used for [[transportation]] and the natural gas not used for [[electricity generation]] is used for [[space heating|space]], [[water heating|water]] and industrial heating. Coal can be converted to gas or liquid fuel, but the efficiencies and economics of such processes can make them unfeasible.{{Citation needed|date=January 2013}} Vehicles or heaters may require modification to use coal-derived fuels. Coal is an impure fuel and produces more [[greenhouse gas]] and [[pollution]] than an equivalent amount of petroleum or natural gas. For instance, the operation of a 1000-MWe coal-fired power plant results in a nuclear radiation dose of 490 person-rem/year, compared to 136 person-rem/year, for an equivalent nuclear power plant including uranium mining, reactor operation and waste disposal.<ref>https://www.ornl.gov/sites/default/files/ORNL%20Review%20v26n3-4%201993.pdf pg28</ref>

{{As of|2009}} the largest coal-fired power station is [[Taichung Power Plant]] in [[Taiwan]]. The world's most energy-efficient coal-fired power plant is the [[Avedøre Power Station]] in [[Denmark]].<ref>[http://www.dongenergy.com/en/business%20activities/generation/electricity%20generation/primary%20power%20stations/pages/avedore%20power%20station.aspx Avedøre Power Station] {{webarchive |url=https://web.archive.org/web/20120225021554/http://www.dongenergy.com/en/business%20activities/generation/electricity%20generation/primary%20power%20stations/pages/avedore%20power%20station.aspx |date=25 February 2012 }} from the web page of [[DONG Energy]]</ref>

===Fuel transport and delivery===
[[File:Grand Junction Trip 92007 098.JPG|thumb|Coal-fired power plants provide about 39 percent of consumed electricity in the United States, as of March 2016.<ref>Siera Magazine</ref> This is the [[Carbon Power Plant|Castle Gate Plant]] near [[Helper, Utah]].]]

Coal is delivered by highway [[truck]], [[railroad|rail]], [[barge]], [[Collier (ship type)|collier]] ship or [[coal slurry pipeline]]. Some plants are even built near coal mines and coal is delivered by conveyors. A large coal [[train]] called a "unit train" may be two kilometers (over a mile) long, containing 130-140 cars with 100 [[short ton]]s of coal in each one, for a total load of over 15,000 tons. A large plant under full load requires at least one coal delivery this size every day. Plants may get as many as three to five trains a day, especially in "peak season" during the hottest summer or coldest winter months (depending on local climate) when power consumption is high. A large thermal power plant such as the now decommissioned [[Nanticoke Generating Station|Nanticoke]], Ontario stores several million metric tons of coal for winter use when the lakes are frozen.

Modern unloaders use rotary dump devices, which eliminate problems with coal freezing in bottom dump cars. The unloader includes a train positioner arm that pulls the entire train to position each car over a coal hopper. The dumper clamps an individual car against a platform that swivels the car upside down to dump the coal. Swiveling couplers enable the entire operation to occur while the cars are still coupled together. Unloading a unit train takes about three hours.

Shorter trains may use railcars with an "air-dump", which relies on air pressure from the engine plus a "hot shoe" on each car. This "hot shoe" when it comes into contact with a "hot rail" at the unloading trestle, shoots an electric charge through the air dump apparatus and causes the doors on the bottom of the car to open, dumping the coal through the opening in the trestle. Unloading one of these trains takes anywhere from an hour to an hour and a half. Older unloaders may still use manually operated bottom-dump rail cars and a "shaker" attached to dump the coal. Generating stations adjacent to a mine may receive coal by [[conveyor belt]] or massive [[diesel-electric]]-drive [[haul truck|trucks]].

A collier (cargo ship carrying coal) may hold 40,000 long tons of coal and takes several days to unload. Some colliers carry their own conveying equipment to unload their own bunkers; others depend on equipment at the plant. For transporting coal in calmer waters, such as rivers and lakes, flat-bottomed [[barge]]s are often used. Barges are usually unpowered and must be moved by [[tugboat]]s or [[towboat]]s.

For start up or auxiliary purposes, the plant may use fuel oil as well. Fuel oil can be delivered to plants by [[Pipeline transport|pipeline]], [[Tanker (ship)|tanker]], [[tank car]] or truck. Oil is stored in vertical cylindrical steel tanks with capacities as high as {{convert|90000|oilbbl}}' worth. The [[viscosity|heavier]] no. 5 "bunker" and no. 6 fuels are typically steam-heated before pumping in cold climates.

===Fuel processing===
Coal is prepared for use by crushing the rough coal to pieces less than {{convert|2|in|cm|sigfig=1}} in size. The coal is then transported from the storage yard to in-plant storage silos by [[conveyor belt]]s at rates up to 4,000 short tons per hour.

In plants that burn pulverized coal, silos feed coal to [[pulverizer]]s (coal mills) that take the larger {{convert|2|in|mm|adj=on}} pieces, grind them to the consistency of [[talcum powder]], sort them, and mix them with primary combustion air which transports the coal to the boiler furnace and preheats the coal in order to drive off excess moisture content. A 500 MWe plant may have six such pulverizers, five of which can supply coal to the furnace at 250 tons per hour under full load.

In plants that do not burn pulverized coal, the larger {{convert|2|in|mm|adj=on}} pieces may be directly fed into the silos which then feed either mechanical distributors that drop the coal on a traveling grate or the [[Cyclone furnace|cyclone]] burners, a specific kind of combustor that can efficiently burn larger pieces of fuel.

==Combined heat and power==
[[Combined heat and power]] (CHP), also known as [[cogeneration]], is the use of a [[thermal power station]] to provide both electric power and heat (the latter being used i.e. for [[district heating]] purposes). This technology is widely practiced in for example Denmark, as well as other Scandinavian countries and parts of Germany. Calculations show that Combined Heat and Power District Heating (CHPDH) is the cheapest method in reducing (but not eliminating) carbon emissions, if conventional fossil fuels remain to be burned.<ref>[http://www.claverton-energy.com/carbon-footprints-of-various-sources-of-heat-chpdh-comes-out-lowest.html Claverton-energy.co.uk]</ref>

==Gas turbine plants==
[[File:GE H series Gas Turbine.jpg|thumb|480 [[megawatt]] GE H series power generation gas turbine]]
[[File:Currant Creek Power Plant.jpg|thumb|Currant Creek Power Plant near [[Mona, Utah]] is a [[natural gas]] fired electrical plant.]]

One type of fossil fuel power plant uses a [[gas turbine]] in conjunction with a [[heat recovery steam generator]] (HRSG). It is referred to as a [[combined cycle]] power plant because it combines the [[Brayton cycle]] of the gas turbine with the [[Rankine cycle]] of the HRSG. The thermal efficiency of these plants has reached a record [[thermal efficiency|heat rate]] of 5690 Btu/(kW·h), or just under 60%, at a facility in Baglan Bay, Wales.<ref>[http://www.ge-energy.com/prod_serv/products/gas_turbines_cc/en/h_system/index.htm GE Power’s H Series Turbine] {{webarchive |url=https://web.archive.org/web/20071111004450/http://www.ge-energy.com/prod_serv/products/gas_turbines_cc/en/h_system/index.htm |date=11 November 2007 }}</ref>

The turbines are fueled either with natural gas, [[syngas]] or fuel oil. While more efficient and faster to construct (a 1,000 MW plant may be completed in as little as 18 months from start of construction), the economics of such plants is heavily influenced by the volatile cost of fuel, normally natural gas. The combined cycle plants are designed in a variety of configurations composed of the number of gas turbines followed by the steam turbine. For example, a 3-1 combined cycle facility has three gas turbines tied to one steam turbine. The configurations range from (1-1), (2-1), (3-1), (4-1), (5-1), to (6-1){{Citation needed|date=January 2013}}

Simple-cycle or open cycle gas turbine plants, without a steam cycle, are sometimes installed as emergency or [[peaking power plant|peaking]] capacity; their thermal efficiency is much lower. The high running cost per hour is offset by the low capital cost and the intention to run such units only a few hundred hours per year. Other gas turbine plants are installed in stages, with an open cycle gas turbine the first stage and additional turbines or conversion to a closed cycle part of future project plans.

===Dash for gas===
In the 1990s was the [[dash for gas]] where 30 gas-fired power stations were built in Britain due to plentiful gas supplies from [[North Sea Gas|North Sea oil wells]]. According to the 2012 forecast by the U.S. Energy Information Administration, 27 gigawatts of capacity from coal-fired generators is to be retired from 175 US coal-fired power plants before 2016.<ref>{{Cite news|last=Gerhardt|first=Tina|date=1 November 2012|title=Record Number of Coal Power Plants Retire|url=http://www.emagazine.com/magazine/by-the-numbers-record-number-of-coal-power-plants-retire|archive-url=https://web.archive.org/web/20121101010101/http://www.emagazine.com/magazine/by%2Dthe%2Dnumbers%2Drecord%2Dnumber%2Dof%2Dcoal%2Dpower%2Dplants%2Dretire|work=[[E-Magazine]]|dead-url=yes|archivedate=1 November 2012}}</ref> Natural gas showed a corresponding jump, increasing by a third over 2011.<ref name="epm_312">Electric Power Monthly, March 2011 (released May 2012), U.S. Energy Information Administration</ref> Some [[Thermal power station|coal power plants]] such as the 1200 MW [[Hearn Generating Station]] have stopped burning coal by switching the plant to natural gas. Coal's share of electricity generation dropped to just over 36%.<ref name="epm_312" /> Natural gas accounted for 81% of new power generation in the US between 2000 and 2010.<ref>[http://www.eia.gov/todayinenergy/detail.cfm?id=2070 Most electric generating capacity additions in the last decade were natural gas-fired - Today in Energy - U.S. Energy Information Administration (EIA)]</ref> Coal-fired generation puts out about twice the amount of carbon dioxide - around 2,000 pounds for every megawatt hour generated - than electricity generated by burning natural gas at 1,100 pounds of [[greenhouse gas]] per megawatt hour. As the fuel mix in the United States has changed to reduce coal and increase natural gas generation, carbon dioxide emissions have unexpectedly fallen. Carbon dioxide measured in the first quarter of 2012 was the lowest recorded of any year since 1992.<ref>cite web |first=Rachel |last=Nuwer |title=A 20-Year Low in U.S. Carbon Emissions |url=http://green.blogs.nytimes.com/2012/08/17/a-20-year-low-in-u-s-carbon-emissions/ |date=August 17, 2012</ref> The [[list of natural gas power stations]] has over 100 power stations that generate between 100MW and 5,600MW of electricity. Natural gas plants are increasing in popularity and in 2014 generated 22% of the worlds total electricity.<ref>[http://www.iea.org/publications/freepublications/publication/KeyWorld2014.pdf pg24 Free publications]</ref>

==Reciprocating engines==
[[Diesel engine]] generator sets are often used for prime power in communities not connected to a widespread power grid. Emergency (standby) power systems may use reciprocating internal combustion engines operated by fuel oil or natural gas. Standby generators may serve as emergency power for a factory or data center, or may also be operated in parallel with the local utility system to reduce peak power demand charge from the utility. Diesel engines can produce strong torque at relatively low rotational speeds, which is generally desirable when driving an [[alternator]], but diesel fuel in long-term storage can be subject to problems resulting from water accumulation and [[chemical decomposition]]. Rarely used generator sets may correspondingly be installed as natural gas or LPG to minimize the fuel system maintenance requirements.

Spark-ignition internal combustion engines operating on gasoline (petrol), [[propane]], or [[Liquefied petroleum gas|LPG]] are commonly used as portable temporary power sources for construction work, emergency power, or recreational uses.

Reciprocating external combustion engines such as the [[Stirling engine]] can be run on a variety of fossil fuels, as well as renewable fuels or industrial waste heat. Installations of Stirling engines for power production are relatively uncommon.

==Environmental impacts==
[[File:Mohave Generating Station 1.jpg|thumb|The [[Mohave Power Station]], a 1,580 [[Megawatt|MW]] coal power station near [[Laughlin, Nevada]], out of service since 2005 due to environmental
restrictions<ref>[http://www.sce.com/PowerandEnvironment/PowerGeneration/MohaveGenerationStation/ SEC Mohave Generation Station] {{webarchive |url=https://web.archive.org/web/20080914140440/http://www.sce.com/PowerandEnvironment/PowerGeneration/MohaveGenerationStation/ |date=14 September 2008 }} Retrieved 24-07-2008</ref>]]
The [[World energy resources and consumption|world's power demands]] are expected to rise 60% by 2030.<ref name=WorldOutlook2004>
{{Citation
|title=World Outlook 2004
|publisher=[[International Energy Agency|IEA]]
|date=October 26, 2004
|url=http://www.iea.org/textbase/nppdf/free/2004/weo2004.pdf
|accessdate=June 13, 2006
|page=31
|location=Paris
|isbn=92-64-10817-3
|deadurl=yes
|archiveurl=https://web.archive.org/web/20060622104453/http://iea.org:80/textbase/nppdf/free/2004/weo2004.pdf
|archivedate=22 June 2006
|df=dmy
}}
</ref>
World organizations and international agencies, like the IEA, are concerned about the [[Environmental impact of fossil fuels|environmental impact of burning fossil fuels]], and coal in particular. The combustion of coal contributes the most to [[acid rain]] and [[air pollution]], and has been connected with [[global warming]]. Due to the chemical composition of coal there are difficulties in removing impurities from the solid fuel prior to its combustion. Modern day coal power plants pollute less than older designs due to new "[[scrubber]]" technologies that filter the exhaust air in smoke stacks; however emission levels of various pollutants are still on average several times greater than natural gas power plants. In these modern designs, pollution from coal-fired power plants comes from the emission of gases such as carbon dioxide, [[nitrogen oxides]], and [[sulfur dioxide]] into the air.

Acid rain is caused by the emission of [[nitrogen oxides]] and [[sulfur dioxide]]. These gases may be only mildly acidic themselves, yet when they react with the atmosphere, they create acidic compounds such as [[sulfurous acid]], [[nitric acid]] and [[sulfuric acid]] which fall as rain, hence the term acid rain. In Europe and the U.S.A., stricter emission laws and decline in heavy industries have reduced the environmental hazards associated with this problem, leading to lower emissions after their peak in 1960s.

{| class="wikitable sortable"
|- class="hintergrundfarbe6"
|+Carbon dioxide and other air pollution of the 9 greatest brown coal power plants in Germany ([[Pollutant release and transfer register|PRTR 2010]])<ref name=PRTR>[http://www.prtr.bund.de/ PRTR - Europäisches Emissionsregister]</ref>
!Power plant
![[carbon dioxide|CO2]] (Tons)
![[nitrogen dioxide|NOx/NO2]] (Tons)
![[sulfur dioxide|SOx/SO2]] (Tons)
!Fine Dust (Tons)
![[mercury (element)|Hg]] (kg)
![[Cadmium|Cd]] (kg)
![[Nickel|Ni]] (kg)
![[Blei|Pb]] (kg)
![[Arsen|As]] (kg)
![[Chromium|Cr]] (kg)
|-
|Power plant Niederaußem|Niederaußem
|style="text-align:right"|28,100,000
|style="text-align:right"|17,900
|style="text-align:right"|6,870
|style="text-align:right"|386
|style="text-align:right"|499
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|49.9
|style="text-align:right"|<100
|-
|Power plant Jänschwalde|Jänschwalde*
|style="text-align:right"|23,800,000
|style="text-align:right"|18,700
|style="text-align:right"|21,400
|style="text-align:right"|573
|style="text-align:right"|592
|style="text-align:right"|<10
|style="text-align:right"|308
|style="text-align:right"|<200
|style="text-align:right"|129
|style="text-align:right"|<100
|-
|Power plant Weisweiler|Weisweiler
|style="text-align:right"|19,900,000
|style="text-align:right"|12,700
|style="text-align:right"|3,060
|style="text-align:right"|456
|style="text-align:right"|271
|style="text-align:right"|<10
|style="text-align:right"|103
|style="text-align:right"|<200
|style="text-align:right"|67
|style="text-align:right"|<100
|-
|Power plant Neurath|Neurath
|style="text-align:right"|16,900,000
|style="text-align:right"|11,700
|style="text-align:right"|3,190
|style="text-align:right"|251
|style="text-align:right"|181
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|42.2
|style="text-align:right"|<100
|-
|Power plant Boxberg|Boxberg
|style="text-align:right"|15,100,000
|style="text-align:right"|10,700
|style="text-align:right"|7,810
|style="text-align:right"|167
|style="text-align:right"|226
|style="text-align:right"|<10
|style="text-align:right"|152
|style="text-align:right"|236
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Frimmersdorf|Frimmersdorf
|style="text-align:right"|14,400,000
|style="text-align:right"|9,070
|style="text-align:right"|5,620
|style="text-align:right"|257
|style="text-align:right"|153
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|35.7
|style="text-align:right"|<100
|-
|Power plant Lippendorf|Lippendorf**
|style="text-align:right"|12,500,000
|style="text-align:right"|8,570
|style="text-align:right"|13,800
|style="text-align:right"|108
|style="text-align:right"|1,160
|style="text-align:right"|68
|style="text-align:right"|1,960
|style="text-align:right"|789
|style="text-align:right"|21
|style="text-align:right"|466
|-
|Power plant Schwarze Pumpe|Schwarze Pumpe
|style="text-align:right"|11,200,000
|style="text-align:right"|4,610
|style="text-align:right"|7,060
|style="text-align:right"|<100
|style="text-align:right"|243
|style="text-align:right"|62.9
|style="text-align:right"|<50
|style="text-align:right"|369
|style="text-align:right"|35.8
|style="text-align:right"|224
|-
|Power plant Schkopau|Schkopau
|style="text-align:right"|5,120,000
|style="text-align:right"|3,320
|style="text-align:right"|4,770
|style="text-align:right"|74.6
|style="text-align:right"|227
|style="text-align:right"|129
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|- class="hintergrundfarbe5"
|Sum without "<"
|style="text-align:right"|147,020,000
|style="text-align:right"|97,270
|style="text-align:right"|73,580
|style="text-align:right"|2,273
|style="text-align:right"|3,552
|style="text-align:right"|260
|style="text-align:right"|2,523
|style="text-align:right"|1,394
|style="text-align:right"|381
|style="text-align:right"|690
|-
|[[Deutschland|DE]] All together 2010<ref name="Trendtabelle">[http://www.umweltbundesamt.de/emissionen/publikationen.htm Emissionsentwicklung 1990 - 2011, klassische Luftschadstoffe, Schwermetalle] Nationale Trendtabellen für die deutsche Berichterstattung atmosphärischer Emissionen seit 1990, Umweltbundesamt (Excel-Tabelle), 2013</ref>
|style="text-align:right"|834,511,385
|style="text-align:right"|1,328,717
|style="text-align:right"|444,035
|style="text-align:right"|211,284
|style="text-align:right"|9,412
|style="text-align:right"|4,723
|style="text-align:right"|105,802
|style="text-align:right"|193,968
|style="text-align:right"|6,120
|style="text-align:right"|55,060
|-
|Share of all together
|style="text-align:right"|18 %
|style="text-align:right"|7.3 %
|style="text-align:right"|17 %
|style="text-align:right"|1.1 %
|style="text-align:right"|38 %
|style="text-align:right"|5.5 %
|style="text-align:right"|2.4 %
|style="text-align:right"|0.7 %
|style="text-align:right"|6.2 %
|style="text-align:right"|1.3 %
|-
|colspan="11"|* with [[Fuel surrogate]] and [[Waste-to-energy]] ** with [[Biosolids#Biosolids|biosolids]]-[[Waste-to-energy]]
|}
{| class="wikitable sortable"
|- class="hintergrundfarbe6"
|+Carbon dioxide and other air pollution of the 14 greatest stone coal power plants in Germany
[[Pollutant release and transfer register|PRTR 2010]]<ref name=PRTR />
!Power plant
![[carbon dioxide|CO2]] (Tons)
![[nitrogen dioxide|NOx/NO2]] (Tons)
![[sulfur dioxide|SOx/SO2]] (Tons)
!Fine dust (Tons)
![[mercury (element)|Hg]] (kg)
![[Cadmium|Cd]] (kg)
![[Nickel|Ni]] (kg)
![[Blei|Pb]] (kg)
![[Arsen|As]] (kg)
![[Chromium|Cr]] (kg)
|-
|Power plant Scholven|Scholven
|style="text-align:right"|9,390,000
|style="text-align:right"|7,090
|style="text-align:right"|4,330
|style="text-align:right"|244
|style="text-align:right"|135
|style="text-align:right"|31
|style="text-align:right"|86
|style="text-align:right"|<200
|style="text-align:right"|51
|style="text-align:right"|<100
|-
|Power plant Mannheim|Mannheim
|style="text-align:right"|6,510,000
|style="text-align:right"|3,550
|style="text-align:right"|1,490
|style="text-align:right"|148
|style="text-align:right"|146
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|68
|style="text-align:right"|<100
|-
|Power plant Voerde|Voerde
|style="text-align:right"|6,240,000
|style="text-align:right"|4,700
|style="text-align:right"|2,840
|style="text-align:right"|<100
|style="text-align:right"|38.3
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Staudinger Großkrotzenburg|Staudinger*
|style="text-align:right"|4,480,000
|style="text-align:right"|2,770
|style="text-align:right"|665
|style="text-align:right"|69.9
|style="text-align:right"|45.6
|style="text-align:right"|19.1
|style="text-align:right"|131
|style="text-align:right"|<200
|style="text-align:right"|113
|style="text-align:right"|192
|-
|Power plant Heyden|Heyden
|style="text-align:right"|3,870,000
|style="text-align:right"|2,920
|style="text-align:right"|1,380
|style="text-align:right"|86.7
|style="text-align:right"|28.4
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Heilbronn|Heilbronn
|style="text-align:right"|3,240,000
|style="text-align:right"|2,160
|style="text-align:right"|1,660
|style="text-align:right"|<100
|style="text-align:right"|34
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Gersteinwerk|Werne*
|style="text-align:right"|3,140,000
|style="text-align:right"|1,900
|style="text-align:right"|1,170
|style="text-align:right"|<100
|style="text-align:right"|11.5
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Wilhelmshaven (E.ON)|Wilhelmshaven
|style="text-align:right"|3,100,000
|style="text-align:right"|2,040
|style="text-align:right"|1,390
|style="text-align:right"|136
|style="text-align:right"|29.9
|style="text-align:right"|11.7
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Bergkamen|Bergkamen
|style="text-align:right"|3,020,000
|style="text-align:right"|2,100
|style="text-align:right"|2,040
|style="text-align:right"|<100
|style="text-align:right"|18.1
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Herne|Herne
|style="text-align:right"|2,480,000
|style="text-align:right"|1,790
|style="text-align:right"|1,340
|style="text-align:right"|<100
|style="text-align:right"|30.3
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Altbach/Deizisau|Altbach**
|style="text-align:right"|2,220,000
|style="text-align:right"|1,350
|style="text-align:right"|906
|style="text-align:right"|<100
|style="text-align:right"|30
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Rheinhafen-Steam-Power plant Karlsruhe|Karlsruhe*
|style="text-align:right"|2,170,000
|style="text-align:right"|1,140
|style="text-align:right"|1,080
|style="text-align:right"|<100
|style="text-align:right"|19
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|-
|Power plant Veltheim|Veltheim**
|style="text-align:right"|1,740,000
|style="text-align:right"|1,290
|style="text-align:right"|400
|style="text-align:right"|52.6
|style="text-align:right"|10.1
|style="text-align:right"|22.4
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|156
|style="text-align:right"|<100
|-
|Power plant Bexbach|Bexbach
|style="text-align:right"|1,300,000
|style="text-align:right"|910
|style="text-align:right"|746
|style="text-align:right"|<100
|style="text-align:right"|<10
|style="text-align:right"|<10
|style="text-align:right"|<50
|style="text-align:right"|<200
|style="text-align:right"|<20
|style="text-align:right"|<100
|- class="hintergrundfarbe5"
|Sum without "<"
|style="text-align:right"|52,900,000
|style="text-align:right"|35,710
|style="text-align:right"|21,437
|style="text-align:right"|737
|style="text-align:right"|576
|style="text-align:right"|84
|style="text-align:right"|217
|style="text-align:right"| -
|style="text-align:right"|388
|style="text-align:right"|192
|-
|[[Deutschland|DE]] All together 2010<ref name="Trendtabelle" />
|style="text-align:right"|834,511,385
|style="text-align:right"|1,328,717
|style="text-align:right"|444,035
|style="text-align:right"|211,284
|style="text-align:right"|9,412
|style="text-align:right"|4,723
|style="text-align:right"|105,802
|style="text-align:right"|193,968
|style="text-align:right"|6,120
|style="text-align:right"|55,060
|-
|Share of all together
|style="text-align:right"|6.3 %
|style="text-align:right"|2.7 %
|style="text-align:right"|4.8 %
|style="text-align:right"|0.3 %
|style="text-align:right"|6.1 %
|style="text-align:right"|1.8 %
|style="text-align:right"|0.2 %
|style="text-align:right"| -
|style="text-align:right"|6.3 %
|style="text-align:right"|0.3 %
|-
|colspan="11"|* with earth gas share, ** with oil- and earth gas share
|}

In 2008, the [[European Environment Agency]] (EEA) documented fuel-dependent emission factors based on actual emissions from power plants in the [[European Union]].<ref name=EEA_AirPollution>
{{Citation
| title = Air pollution from electricity-generating large combustion plants
| publisher = European Environment Agency (EEA)
| year = 2008
| url = http://www.eea.europa.eu/publications/technical_report_2008_4/at_download/file
| format=PDF
| accessdate =
| pages =
| location = Copenhagen
| isbn = 978-92-9167-355-1 }}
</ref>
{| class="wikitable"
|-
! Pollutant !! Hard coal !! Brown coal !! Fuel oil !! Other oil !! Gas
|-
| CO2 (g/GJ) || 94,600 || 101,000 || 77,400 || 74,100 || 56,100
|-
| SO2 (g/GJ) || 765 || 1,361 || 1,350 || 228 || 0.68
|-
| NOx (g/GJ) || 292 || 183 || 195 || 129 || 93.3
|-
| CO (g/GJ) || 89.1 || 89.1 || 15.7 || 15.7 || 14.5
|-
| Non methane organic compounds (g/GJ) || 4.92 || 7.78 || 3.70 || 3.24 || 1.58
|-
| Particulate matter (g/GJ) || 1,203 || 3,254 || 16 || 1.91 || 0.1
|-
| Flue gas volume total (m3/GJ) || 360 || 444 || 279 || 276 || 272
|}

===Carbon dioxide===
{{Main|Carbon dioxide}}
[[File:Taichung Thermal Power Plant.JPG|thumb|[[Taichung Power Plant|Taichung coal-fired power plant]] in [[Taiwan]], the world's largest carbon dioxide emitter<ref>[http://thephoenixsun.com/archives/6548 The Phoenix Sun | Dirty numbers | The 200 Most Polluting Power Plants in the World]</ref>]]

Electricity generation using carbon based fuels is responsible for a large fraction of carbon dioxide (CO2) emissions worldwide and for 34% of U.S. man-made carbon dioxide emissions in 2010. In the U.S. 70% of electricity generation is produced from combustion of fossil fuels.<ref>{{cite web
|url= http://www.epa.gov/climatechange/ghgemissions/sources.html
|title=Sources Climate Change
|work= US EPA
|year=2012
|accessdate=August 26, 2012}}</ref>

Of the fossil fuels, coal is much more carbon intensive than oil or natural gas, resulting in greater volumes of [[carbon dioxide]] emissions per unit of electricity generated. In 2010, coal contributed about 81% of CO2 emissions from generation and contributed about 45% of the electricity generated in the United States.<ref>{{cite web
|url= http://www.epa.gov/climatechange/ghgemissions/sources/electricity.html
|title=Electricity Sector Emissions Climate Change
|work= US EPA
|year=2012
|accessdate=August 26, 2012}}</ref> In 2000, the carbon intensity of U.S. coal thermal combustion was 2249 lbs/MWh (1,029 kg/MWh)<ref>[http://www.epa.gov/cleanrgy/energy-and-you/affect/coal.html ''US EPA Clean Energy—Coal'']</ref> while the carbon intensity of U.S. oil thermal generation was 1672 lb/MWh (758 kg/MWh or 211 kg/[[gigajoule|GJ]])<ref>[http://www.epa.gov/cleanrgy/energy-and-you/affect/oil.html ''US EPA Clean Energy—Oil]</ref> and the carbon intensity of U.S. natural gas thermal production was 1135 lb/MWh (515 kg/MWh or 143 kg/GJ).<ref>[http://www.epa.gov/cleanrgy/energy-and-you/affect/natural-gas.html ''US EPA Clean Energy—Gas'']</ref>

The Intergovernmental Panel on Climate Change (see [[IPCC]]) states that carbon dioxide is a greenhouse gas and that increased quantities within the atmosphere will "very likely" lead to higher average temperatures on a global scale ([[global warming]]); concerns regarding the potential for such warming to change the global climate prompted IPCC recommendations calling for large cuts to CO2 emissions worldwide.<ref name="ipcc summary">{{cite web|url=http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf|title=Summary for policymakers|last=Solomon, S.|year=2007|work=A report of Working Group I of the Intergovernmental Panel on Climate Change|publisher=IPCC|accessdate=24 March 2010|display-authors=etal}}</ref>

Emissions may be reduced through more efficient and higher combustion temperature and through more efficient production of electricity within the cycle. [[Carbon capture and storage]] (CCS) of emissions from coal-fired power stations is another alternative but the technology is still being developed and will increase the cost of fossil fuel-based production of electricity. CCS may not be economically viable, unless the price of emitting CO2 to the atmosphere rises.

===Particulate matter===
Another problem related to coal combustion is the emission of [[Atmospheric particulate matter|particulates]] that have a serious impact on public health. Power plants remove particulate from the flue gas with the use of a [[Dust collector#Fabric filters|bag house]] or [[electrostatic precipitator]]. Several newer plants that burn coal use a different process, [[Combined cycle#Integrated Gasification Combined Cycle (IGCC)|Integrated Gasification Combined Cycle]] in which [[synthesis gas]] is made out of a reaction between coal and water. The synthesis gas is processed to remove most pollutants and then used initially to power gas turbines. Then the hot exhaust gases from the gas turbines are used to generate steam to power a steam turbine. The pollution levels of such plants are drastically lower than those of "classic" coal power plants.<ref>{{Citation
| title = Energy research at DOE: was it worth it? Energy efficiency and fossil energy research 1978 to 2000
| place =
| publisher = National Academies Press
| year = 2001
| volume =
| edition =
| page = 174
| url =
| doi =
| id =
| isbn = 0-309-07448-7
| author = Committee on Benefits of DOE R&D on Energy Efficiency and Fossil Energy, [[United States National Research Council|US NRC]]}}
</ref>

Particulate matter from coal-fired plants can be harmful and have negative health impacts. Studies have shown that exposure to particulate matter is related to an increase of respiratory and cardiac mortality.<ref name="Nel, A. 2005">Nel, A. (2005, May 6). Air Pollution-Related Illness: Effects of Particles. Science, 308(5723), 804-806.</ref> Particulate matter can irritate small airways in the lungs, which can lead to increased problems with asthma, chronic bronchitis, airway obstruction, and gas exchange.<ref name="Nel, A. 2005"/>

There are different types of particulate matter, depending on the chemical composition and size. The dominant form of particulate matter from coal-fired plants is [[Fly ash|coal fly ash]], but secondary sulfate and nitrate also comprise a major portion of the particulate matter from coal-fired plants.<ref name="Grahame, T. 2007">Grahame, T., & Schlesinger, R. (2007, April 15). Health Effects of Airborne Particulate Matter: Do We Know Enough to Consider Regulating Specific Particle Types or Sources?. Inhalation Toxicology, 19(6–7), 457–481.</ref> Coal fly ash is what remains after the coal has been combusted, so it consists of the incombustible materials that are found in the coal.<ref name="Schobert, H. H. 2002">Schobert, H. H. (2002). ''Energy and Society.'' New York: Taylor & Francis, 241–255.</ref>

The size and chemical composition of these particles affects the impacts on human health.<ref name="Nel, A. 2005"/><ref name="Grahame, T. 2007"/> Currently coarse (diameter greater than 2.5 μm) and fine (diameter between 0.1 μm and 2.5 μm) particles are regulated, but ultrafine particles (diameter less than 0.1 μm) are currently unregulated, yet they pose many dangers.<ref name="Nel, A. 2005"/> Unfortunately much is still unknown as to which kinds of particulate matter pose the most harm, which makes it difficult to come up with adequate legislation for regulating particulate matter.<ref name="Grahame, T. 2007"/>

There are several methods of helping to reduce the particulate matter emissions from coal-fired plants. Roughly 80% of the ash falls into an ash hopper, but the rest of the ash then gets carried into the atmosphere to become coal-fly ash.<ref name="Schobert, H. H. 2002"/> Methods of reducing these emissions of particulate matter include:
#a [[Baghouse#Fabric filters|baghouse]]
#an [[electrostatic precipitator]] (ESP)
#[[Combined cycle#Integrated Gasification Combined Cycle (IGCC)|cyclone collector]]
The baghouse has a fine filter that collects the ash particles, electrostatic precipitators use an electric field to trap ash particles on high-voltage plates, and cyclone collectors use centrifugal force to trap particles to the walls.<ref name="Schobert, H. H. 2002"/> A recent study indicates that sulfur emissions from fossil fueled power stations in China may have caused a 10-year lull in global warming (1998-2008)<ref>Washington Post 7-5-2011 | http://www.washingtonpost.com/blogs/capital-weather-gang/post/new-study-blames-10-year-lull-in-global-warming-on-china-coal-use-air-pollution/2011/07/05/gHQAwjV8yH_blog.html</ref>

===Radioactive trace elements===
Coal is a sedimentary rock formed primarily from accumulated plant matter, and it includes many inorganic minerals and elements which were deposited along with organic material during its formation. As the rest of the Earth's [[Crust (geology)|crust]], coal also contains low levels of [[uranium]], [[thorium]], and other naturally occurring [[radioactive isotopes]] whose release into the environment leads to [[radioactive contamination]]. While these substances are present as very small trace impurities, enough coal is burned that significant amounts of these substances are released. A 1,000 MW coal-burning power plant could have an uncontrolled release of as much as 5.2 metric tons per year of uranium (containing {{convert|74|lb|kg}} of [[uranium-235]]) and 12.8 metric tons per year of thorium.<ref name="ORNL">[http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html Coal Combustion: Nuclear Resource or Danger?] {{webarchive |url=https://web.archive.org/web/20070205103749/http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html |date=5 February 2007 }} by Alex Gabbard, [[ORNL]] Review, Summer/Fall 1993, Vol. 26, Nos. 3 and 4.</ref> In comparison, a 1,000 MW nuclear plant will generate about 30 metric tons of high-level radioactive solid packed waste per year.<ref>{{cite web|last1=Thompson|first1=Linda|title=Vitrification of Nuclear Waste|url=http://large.stanford.edu/courses/2010/ph240/thompson2/|website=PH240 - Fall 2010: Introduction to the Physics of Energy|publisher=Stanford University|accessdate=10 August 2014}}</ref> It is estimated that during 1982, US coal burning released 155 times as much uncontrolled radioactivity into the atmosphere as the [[Three Mile Island incident]].<ref>[http://www.physics.ohio-state.edu/~aubrecht/coalvsnucMarcon.pdf#page=8 Physics.ohio-state.edu]</ref> The collective radioactivity resulting from all coal burning worldwide between 1937 and 2040 is estimated to be 2,700,000 curies or 0.101 EBq.<ref name="ORNL" /> During normal operation, the effective dose equivalent from coal plants is 100 times that from nuclear plants.<ref name="ORNL" /> Normal operation however, is a deceiving baseline for comparison: just the [[Chernobyl disaster|Chernobyl nuclear disaster]] released, in iodine-131 alone, an estimated 1.76 EBq .<ref name="newscientist1">{{cite web|url=http://www.newscientist.com/article/dn20285-fukushima-radioactive-fallout-nears-chernobyl-levels.html |title=Fukushima radioactive fallout nears Chernobyl levels |publisher=Newscientist.com |accessdate=24 April 2011}}</ref> of radioactivity, a value one order of magnitude above this value for total emissions from all coal burned within a century, while the iodine-131, the major radioactive substance which comes out in accident situations, has a half life of just 8 days.

===Water and air contamination by coal ash===
A study released in August 2010 that examined state pollution data in the United States by the organizations [[Environmental Integrity Project]], the [[Sierra Club]] and [[Earthjustice]] found that coal ash produced by coal-fired power plants dumped at sites across 21 U.S. states has contaminated ground water with toxic elements. The contaminants including the poisons [[arsenic]] and [[lead]].<ref name="mcclatchydc.com">[http://www.mcclatchydc.com/2010/08/26/99728/study-of-coal-ash-sites-finds.html "Study of Coal Ash Sites Finds Extensive Water Contamination"] ''McClatchy''; also archived at: [http://www.commondreams.org/headline/2010/08/27-4 commondreams.org]</ref>

Arsenic has been shown to cause [[skin cancer]], [[bladder cancer]] and [[lung cancer]], and lead damages the [[nervous system]].<ref name=EJ2010>EarthJustice news release, 2010 Sept. 16, [http://unearthed.earthjustice.org/blog/2010-september/new-report-coal-ash-linked-cancer-and-other-maladies "New Report—Coal Ash Linked To Cancer and Other Maladies; Coal's Waste Is Poisoning Communities in 34 States"] {{webarchive |url=https://web.archive.org/web/20100919000203/http://unearthed.earthjustice.org/blog/2010-september/new-report-coal-ash-linked-cancer-and-other-maladies |date=19 September 2010 }} Earthjustice.org and [[Physicians for Social Responsibility]], [http://earthjustice.org/sites/default/files/files/CoalAsh_Earthjustice.pdf "Coal Ash: The Toxic Threat to Our Communities and Our Environment"] 2010 September 16, earthjustice.org</ref> Coal ash contaminants are also linked to respiratory diseases and other health and developmental problems, and have disrupted local aquatic life.<ref name="mcclatchydc.com"/> Coal ash also releases a variety of toxic contaminants into nearby air, posing a health threat to those who breath in fugitive coal dust.
<ref name=EJ2010/>

Currently, the EPA does not regulate the disposal of coal ash; regulation is up to the states and the electric power industry has been lobbying to maintain this status quo. Most states require no monitoring of drinking water near coal ash dump sites. The study found an additional 39 contaminated U.S. sites and concluded that the problem of coal ash-caused water contamination is even more extensive in the United States than has been estimated. The study brought to 137 the number of ground water sites across the United States that are contaminated by power plant-produced coal ash.<ref name="mcclatchydc.com"/>

====Mercury contamination====
{{Main|Mercury (element)}}

U.S. government scientists tested fish in 291 streams around the country for [[mercury contamination]]. They found mercury in every fish tested, according to the study by the [[U.S. Department of the Interior]]. They found mercury even in fish of isolated rural waterways. Twenty five percent of the fish tested had mercury levels above the safety levels determined by the [[U.S. Environmental Protection Agency]] for people who eat the fish regularly. The largest source of mercury contamination in the United States is coal-fueled power plant emissions.<ref>[https://www.nytimes.com/2009/08/20/science/earth/20brfs-MERCURYFOUND_BRF.html?_r=1&em nytimes.com "Mercury Found in Every Fish Tested, Scientists Say"] ''New York Times'', 2009 Aug. 19</ref>

==Greening of fossil fuel power plants==
{{Main|Coal pollution mitigation|Landfill#Reclaiming materials}}
{{Further|Zero Emission Fossil Fuel Power Plants}}
Several methods exist to improve the efficiency of fossil fuel power plants. A frequently used and cost-efficient method is to convert a plant to run on a different fuel. This includes conversions of coal power plants to biomass or waste<ref>[http://www.archives-suez.com/document/?f=developpement-durable/en/awirs_en.pdf Coal to biomass power plant conversion]</ref><ref>[http://www.25x25.org/index.php?option=com_content&task=view&id=579&Itemid=191 Coal to biomass conversion by Georgia Power]</ref><ref>[http://www.ist-world.org/ProjectDetails.aspx?ProjectId=a6556d81d97d41d2be8e31759221b824 Conversion of coal to waste-fired power plant]</ref> and conversions of natural gas power plants to biogas. Conversions of coal powered power plants to waste-fired power plants have an extra benefit in that they can reduce [[landfill]]ing. In addition, waste-fired power plants can be equipped with material recovery, which is also beneficial to the environment. In some instances, [[torrefaction]] of biomass may be needed if biomass is the material the converted fossil fuel power plant will be using.<ref>[https://www.ecn.nl/nl/nieuws/item/successful-test-with-innovative-renewable-energy-source-at-amer-power-plant/ Torrefaction of biomass sometimes needed when using biomass in converted FFPS]</ref>

Improving energy efficiency of a coal-fired power plant also reduces emissions. For example, emissions can be reduced by upgrading existing plants or building new high-efficiency, low-emissions plants. Such plants emit almost 20% less CO2 than a subcritical unit operating at a similar load. Over the longer term, HELE plants can further facilitate emission reductions because coal-fired plants operating at the highest efficiencies are also the most appropriate option for [[carbon capture and storage]] retrofit.<ref>{{cite web
|url= http://cornerstonemag.net/upgrading-the-efficiency-of-the-worlds-coal-fleet-to-reduce-co2-emissions/
|title=Upgrading the Efficiency of the World's Coal Fleet to Reduce CO2 Emissions
|first= Ian
|last= Barnes
|publisher= Cornerstone
|date= March 2015
|accessdate= }}</ref>

Regardless of the conversion, a truly low-carbon fossil fuel power plant implements carbon capture and storage, which means that the exhaust CO2 is not released into the environment and the fossil fuel power plant becomes an [https://web.archive.org/web/20090705094616/http://www.zero-emissionplatform.eu:80/website/library/ emissionless power plant]. A 2006 example of a carbon capture and storage fossil fuel power plant is the pilot Elsam power station near Esbjerg, Denmark.<ref>{{cite web
|url= http://www.ens-newswire.com/ens/mar2006/2006-03-15-06.asp
|title=Europe Tests Carbon Capture at Coal-Fired Power Plant
|last=ENS
|publisher=Environment News Service
|date= March 15, 2006
|accessdate= 15 July 2012}}</ref>

===Coal Pollution Mitigation===
[[Coal pollution mitigation|Coal Pollution Mitigation]] is a process whereby coal is chemically washed of [[mineral]]s and impurities, sometimes [[Gasification|gasified]], burned and the resulting flue gases treated with steam, with the purpose of removing sulfur dioxide, and reburned so as to make the carbon dioxide in the flue gas economically recoverable, and storable underground (the latter of which is called "carbon capture and storage"). The coal industry uses the term "clean coal" to describe technologies designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation and use,<ref>[http://www.australiancoal.com.au/cleanoview.htm AustralianCoal.com.au] {{webarchive |url=https://web.archive.org/web/20071207111230/http://www.australiancoal.com.au/cleanoview.htm |date=7 December 2007 }}—Clean Coal Overview</ref> but has provided no specific quantitative limits on any emissions, particularly carbon dioxide. Whereas contaminants like sulfur or mercury can be removed from coal, carbon cannot be effectively removed while still leaving a usable fuel, and clean coal plants without carbon sequestration and storage do not significantly reduce carbon dioxide emissions. [[James Hansen]] in an open letter to U.S. President [[Barack Obama]] has advocated a "moratorium and phase-out of coal plants that do not capture and store CO2". In his book ''[[Storms of My Grandchildren]]'', similarly, Hansen discusses his ''Declaration of Stewardship'' the first principle of which requires "a moratorium on coal-fired power plants that do not capture and sequester carbon dioxide".<ref>{{Cite book|author=Hansen, James |title=Storms of My Grandchildren |publisher=Bloomsbury Publishing |location=London |year=2009 |isbn=1-4088-0745-9 |page=242 }}</ref>

===Clean gas===
Gas-fired power plants can also be modified to run on [[hydrogen]], the latter of which can be created on-site from natural gas.<ref>[https://energy.gov/eere/fuelcells/hydrogen-production-natural-gas-reforming Natural gas to hydrogen: Natural gas reforming]</ref> Since 2013, the conversion process has been improved by scientists at Karlsruhe Liquid-metal Laboratory (KALLA) as they succeeded in allowing the soot to be easily removed (soot is a byproduct of the process and damaged the working parts in the past -most notably the nickel-iron-cobaltcatalyst-).<ref>[https://www.newscientist.com/article/mg23230940-200-crack-methane-for-fossil-fuels-without-tears/ The reaction that would give us clean fossil fuels forever]</ref><ref>[https://phys.org/news/2013-04-hydrogen-methane-co2-emissions.html Hydrogen from methane without CO2 emissions]</ref> The soot (which contains the carbon) can then be stored underground and is not released into the atmosphere.

==Alternatives to fossil fuel power plants==
{{split section|date=November 2015}}
[[File:U.S. 2014 Electricity Generation By Type.png|thumb|U.S. 2014 Electricity Generation By Type.<ref>[http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01 EIA - Electricity Data]</ref>]]
Alternatives to fossil fuel power plants include [[nuclear power]], [[solar power]], [[geothermal power]], [[wind power]], [[tidal power]], hydroelectric power ([[hydroelectricity]]), [[Biomass|biomass power plants]] and other [[renewable energy|renewable energies]] (see [[non-carbon economy]]). Some of these are proven technologies on an industrial scale (i.e. nuclear, wind, tidal, hydroelectric and biomass fired power) others are still in prototype form.

Nuclear power, and geothermal power may be classed as heat pollutants as they add heat energy to the biosphere that would not otherwise be released.{{Citation needed|date=January 2013}} The net quantity of energy conversion within the biosphere due to the utilisation of wind power, solar power, tidal power, hydroelectric power (hydroelectricity) is static and is derived from the effects of sunlight and the movement of the moon and planets.

Generally, the cost of electrical energy produced by non fossil fuel burning power plants is greater than that produced by burning fossil fuels. This statement however only includes the cost to produce the electrical energy and does not take into account indirect costs associated with the many pollutants created by burning fossil fuels (e.g. increased hospital admissions due to respiratory diseases caused by fine smoke particles).

===Relative cost by generation source===
{{See also|Relative cost of electricity generated by different sources}}

When comparing power plant costs, it is customary to start by calculating the cost of power at the generator terminals by considering several main factors. External costs such as connections costs, the effect of each plant on the distribution grid are considered separately as an additional cost to the calculated power cost at the terminals.

Initial factors considered are:
*Capital costs, including waste disposal and decommissioning costs for nuclear energy.
*Operating and maintenance costs.
*Fuel costs for fossil fuel and biomass sources, and which may be negative for wastes.
*Likely annual hours per year run or load factor, which may be as low as 30% for wind energy, or as high as 90% for nuclear energy.
*Offset sales of heat, for example in combined heat and power district heating (CHP/DH).

These costs occur over the 30–50 year life of the fossil fuel power plants, using [[discounted cash flow]]s. In general large fossil plants are attractive due to their low initial capital costs—typically around £750–£1000 per kilowatt electrical compared to perhaps £1500 per kilowatt for onshore wind.{{Citation needed|date=November 2010}}

== Usage in competitive ==
{{Coalplant/MapLeagueInclusionTable}}

{{Active Maps Navbox}}{{All Maps Navbox|y}}

Metalworks

2017-08-09T21:17:13Z

81.147.69.112:

{{stub}}
{{Imageupdate}}
{{NewInfobox Map
|name=
|image=
|caption=

|maptype=5cp
|filename=cp_metalworks
|version=Official Release
|author1=Ian "Scorpio Uprising" Cuslidge
|author1steam=76561197977081885
|author2=
|author2steam=
|author3=
|author3steam=
|released=3 March 2010
|updated=16 August 2016
|official=1

|gamemode1=6v6
|gamemode2=
|gamemode3=
|adapted=
|pro=
|popularity=moderate
|lpleague=
|lpseason=

|download=http://fakkelbrigade.eu/maps/cp_metalworks.bsp
|workshop=454115745
|tf2maps=12265
|gamebanana=
|tftv=5723
|tftv2=
|etf2l=
|ugc=
|officialwiki=Metalworks
|officialwiki2=Metalworks_(competitive)

|footnotes=
}}
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing fusion, which is distinct from lower temperature metal-joining techniques such as brazing and soldering, which do not melt the base metal. In addition to melting the base metal, a filler material is typically added to the joint to form a pool of molten material (the weld pool) that cools to form a joint that is usually stronger than the base material. Pressure may also be used in conjunction with heat, or by itself, to produce a weld.

Although less common, there are also solid state welding processes such as friction welding or shielded active gas welding in which metal does not melt.

Some of the best known welding methods include:

Oxy-fuel welding – also known as oxyacetylene welding or oxy welding, uses fuel gases and oxygen to weld and cut metals.
Shielded metal arc welding (SMAW) – also known as "stick welding or electric welding", uses an electrode that has flux around it to protect the weld puddle. The electrode holder holds the electrode as it slowly melts away. Slag protects the weld puddle from atmospheric contamination.
Gas tungsten arc welding (GTAW) – also known as TIG (tungsten, inert gas), uses a non-consumable tungsten electrode to produce the weld. The weld area is protected from atmospheric contamination by an inert shielding gas such as argon or helium.
Gas metal arc welding (GMAW) – commonly termed MIG (metal, inert gas), uses a wire feeding gun that feeds wire at an adjustable speed and flows an argon-based shielding gas or a mix of argon and carbon dioxide (CO2) over the weld puddle to protect it from atmospheric contamination.
Flux-cored arc welding (FCAW) – almost identical to MIG welding except it uses a special tubular wire filled with flux; it can be used with or without shielding gas, depending on the filler.
Submerged arc welding (SAW) – uses an automatically fed consumable electrode and a blanket of granular fusible flux. The molten weld and the arc zone are protected from atmospheric contamination by being "submerged" under the flux blanket.
Electroslag welding (ESW) – a highly productive, single pass welding process for thicker materials between 1 inch (25 mm) and 12 inches (300 mm) in a vertical or close to vertical position.
Electric resistance welding (ERW) – a welding process that produces coalescence of laying surfaces where heat to form the weld is generated by the electrical resistance of the material. In general, an efficient method, but limited to relatively thin material.
Many different energy sources can be used for welding, including a gas flame, an electric arc, a laser, an electron beam, friction, and ultrasound. While often an industrial process, welding may be performed in many different environments, including in open air, under water, and in outer space. Welding is a hazardous undertaking and precautions are required to avoid burns, electric shock, vision damage, inhalation of poisonous gases and fumes, and exposure to intense ultraviolet radiation.

Until the end of the 19th century, the only welding process was forge welding, which blacksmiths had used for centuries to join iron and steel by heating and hammering. Arc welding and oxyfuel welding were among the first processes to develop late in the century, and electric resistance welding followed soon after. Welding technology advanced quickly during the early 20th century as the world wars drove the demand for reliable and inexpensive joining methods. Following the wars, several modern welding techniques were developed, including manual methods like SMAW, now one of the most popular welding methods, as well as semi-automatic and automatic processes such as GMAW, SAW, FCAW and ESW. Developments continued with the invention of laser beam welding, electron beam welding, magnetic pulse welding (MPW), and friction stir welding in the latter half of the century. Today, the science continues to advance. Robot welding is commonplace in industrial settings, and researchers continue to develop new welding methods and gain greater understanding of weld quality.

==History==
[[Image:QtubIronPillar.JPG|thumb|The iron pillar of Delhi]]

The history of joining metals goes back several millennia. Called [[forge welding]], the earliest examples come from the [[Bronze Age|Bronze]] and [[Iron Age]]s in [[Europe]] and the [[Middle East]]. The ancient Greek historian [[Herodotus]] states in ''[[Histories (Herodotus)|The Histories]]'' of the 5th century BC that Glaucus of Chios "was the man who single-handedly invented iron welding".<ref>Herodotus. ''The Histories''. Trans. R. Waterfield. Oxford: Oxford University Press. Book One, 25.</ref> Welding was used in the construction of the [[Iron pillar of Delhi]], erected in [[Delhi]], India about 310 AD and weighing 5.4 [[metric tons]].<ref>{{harvnb|Cary|Helzer|2005|p=4}}</ref>

The [[Middle Ages]] brought advances in forge welding, in which blacksmiths pounded heated metal repeatedly until bonding occurred. In 1540, [[Vannoccio Biringuccio]] published ''[[De la pirotechnia]]'', which includes descriptions of the forging operation.<ref name="LE111">Lincoln Electric, p. 1.1-1</ref> [[Renaissance]] craftsmen were skilled in the process, and the industry continued to grow during the following centuries.<ref name="LE111" />

In 1800, [[Humphry Davy|Sir Humphry Davy]] discovered the short-pulse electrical arc and presented his results in 1801.<ref>Lincoln Electric, The Procedure Handbook Of Arc Welding 14th ed., page 1.1{{hyphen}}1</ref><ref name="Ayrton">Hertha Ayrton. ''The Electric Arc'', pp. [https://archive.org/stream/electricarc00ayrtrich#page/20/mode/2up 20], [https://archive.org/stream/electricarc00ayrtrich#page/24/mode/2up 24] and [https://archive.org/stream/electricarc00ayrtrich#page/94/mode/2up 94]. D. Van Nostrand Co., New York, 1902.</ref><ref name="anders">{{Cite journal|doi=10.1109/TPS.2003.815477 |title=Tracking down the origin of arc plasma science-II. early continuous discharges |year=2003 |author=A. Anders |journal=IEEE Transactions on Plasma Science |volume=31 |pages=1060–9 |issue=5}}</ref> In 1802, Russian scientist [[Vasily Vladimirovich Petrov|Vasily Petrov]] created the continuous electric arc,<ref name="anders" /><ref>[[Great Soviet Encyclopedia]], Article ''"Дуговой разряд"'' (eng. ''electric arc'')</ref><ref>{{Citation|last=Lazarev |first=P.P. |title=Historical essay on the 200 years of the development of natural sciences in Russia |journal=[[Physics-Uspekhi]] |volume=42 |issue=1247 |pages=1351–1361 |date=December 1999 |url=http://ufn.ru/ufn99/ufn99_12/Russian/r9912h.pdf |format=Russian |archiveurl=http://www.webcitation.org/5lmBpznUV?url=http://ufn.ru/ufn99/ufn99_12/Russian/r9912h.pdf |archivedate=2009-12-04 |doi=10.1070/PU1999v042n12ABEH000750 |deadurl=yes |df= }}</ref> and subsequently published "News of Galvanic-Voltaic Experiments" in 1803, in which he described experiments carried out in 1802. Of great importance in this work was the description of a stable arc discharge and the indication of its possible use for many applications, one being melting metals.<ref name="biog1">{{cite web |title= Encyclopedia.com. Complete Dictionary of Scientific Biography |url=http://www.encyclopedia.com/doc/1G2-2830903379.html |date=2008 |work= |publisher= Charles Scribner's Sons |accessdate=9 October 2014}}</ref> In 1808, Davy, who was unaware of Petrov's work, rediscovered the continuous electric arc.<ref name="Ayrton" /><ref name="anders" /> In 1881–82 inventors [[Nikolai Benardos]] (Russian) and [[Stanisław Olszewski]] (Polish)<ref>Nikołaj Benardos, Stanisław Olszewski, "Process of and apparatus for working metals by the direct application of the electric current" patent nr 363 320, Washington, United States Patent Office, 17 may 1887.</ref> created the first electric arc welding method known as [[carbon arc welding]] using carbon electrodes. The advances in arc welding continued with the invention of metal electrodes in the late 1800s by a Russian, [[Nikolai Slavyanov]] (1888), and an American, [[C. L. Coffin]] (1890). Around 1900, A. P. Strohmenger released a coated metal electrode in [[United Kingdom|Britain]], which gave a more stable arc. In 1905, Russian scientist Vladimir Mitkevich proposed using a three-phase electric arc for welding. In 1919, [[alternating current]] welding was invented by C. J. Holslag but did not become popular for another decade.<ref>{{harvnb|Cary|Helzer|2005|pp=5–6}}</ref>

Resistance welding was also developed during the final decades of the 19th century, with the first patents going to [[Elihu Thomson]] in 1885, who produced further advances over the next 15 years. [[Thermite welding]] was invented in 1893, and around that time another process, oxyfuel welding, became well established. [[Acetylene]] was discovered in 1836 by [[Edmund Davy]], but its use was not practical in welding until about 1900, when a suitable [[gas welding#Torch|torch]] was developed.<ref>{{harvnb|Cary|Helzer|2005|p=6}}</ref> At first, oxyfuel welding was one of the more popular welding methods due to its portability and relatively low cost. As the 20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding, as advances in metal coverings (known as [[flux (metallurgy)|flux]]) were made.<ref name="Weman26">Weman, p. 26</ref> Flux covering the electrode primarily shields the base material from impurities, but also stabilizes the arc and can add alloying components to the weld metal.<ref name='ESAB'>{{cite web |title=Lesson 3: Covered Electrodes for Welding Mild Steels |url=http://www.esabna.com/euweb/awtc/lesson3_6.htm |date= |work= |publisher= |accessdate=18 May 2017}}</ref>

[[Image:Maurzyce 2009 (0).jpg|thumb|Bridge of Maurzyce]]
World War I caused a major surge in the use of welding processes, with the various military powers attempting to determine which of the several new welding processes would be best. The British primarily used arc welding, even constructing a ship, the "Fullagar" with an entirely welded hull.<ref>[http://www.weldinghistory.org/whfolder/folder/wh1900.html A History of Welding]. weldinghistory.org</ref><ref>[http://www.gracesguide.co.uk/The_Engineer ''The Engineer''] (6 February 1920) p. 142</ref> Arc welding was first applied to aircraft during the war as well, as some German airplane fuselages were constructed using the process.<ref>Lincoln Electric, p. 1.1–5</ref> Also noteworthy is the first welded road bridge in the world, the [[Maurzyce Bridge]] designed by [[Stefan Bryła]] of the [[Lwów University of Technology]] in 1927, and built across the river [[Słudwia River|Słudwia]] near [[Łowicz]], Poland in 1928.<ref>{{cite web|url=http://www.weldinghistory.org/whistoryfolder/welding/wh_1900-1950.html |title=Welding Timeline 1900–1950 |last=Sapp |first=Mark E. |date=February 22, 2008 |publisher=WeldingHistory.org |accessdate=2008-04-29 |deadurl=yes |archiveurl=https://web.archive.org/web/20080803060938/http://www.weldinghistory.org/whistoryfolder/welding/wh_1900-1950.html |archivedate=August 3, 2008 }}</ref>
[[File:Acetylene welding on cylinder water jacket., 1918 - NARA - 530779.tif|thumb|left|170px|Acetylene welding on cylinder water jacket, US Army 1918]]
During the 1920s, major advances were made in welding technology, including the introduction of automatic welding in 1920, in which electrode wire was fed continuously. [[Shielding gas]] became a subject receiving much attention, as scientists attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere. Porosity and brittleness were the primary problems, and the solutions that developed included the use of [[hydrogen]], [[argon]], and [[helium]] as welding atmospheres.<ref>{{harvnb|Cary|Helzer|2005|p=7}}</ref> During the following decade, further advances allowed for the welding of reactive metals like [[aluminium|aluminum]] and [[magnesium]]. This in conjunction with developments in automatic welding, alternating current, and fluxes fed a major expansion of arc welding during the 1930s and then during World War II.<ref>Lincoln Electric, p. 1.1–6</ref> In 1930, the first all-welded merchant vessel, [[M/S Carolinian]], was launched.

During the middle of the century, many new welding methods were invented. In 1930, Kyle Taylor was responsible for the release of [[stud welding]], which soon became popular in shipbuilding and construction. Submerged arc welding was invented the same year and continues to be popular today. In 1932 a Russian, [[Konstantin Khrenov]] successfully implemented the first underwater electric arc welding. [[Gas tungsten arc welding]], after decades of development, was finally perfected in 1941, and gas metal arc welding followed in 1948, allowing for fast welding of non-[[ferrous]] materials but requiring expensive shielding gases. Shielded metal arc welding was developed during the 1950s, using a flux-coated consumable electrode, and it quickly became the most popular metal arc welding process. In 1957, the flux-cored arc welding process debuted, in which the self-shielded wire electrode could be used with automatic equipment, resulting in greatly increased welding speeds, and that same year, [[plasma arc welding]] was invented. Electroslag welding was introduced in 1958, and it was followed by its cousin, [[electrogas welding]], in 1961.<ref>{{harvnb|Cary|Helzer|2005|p=9}}</ref> In 1953, the Soviet scientist N. F. Kazakov proposed the [[diffusion welding|diffusion bonding]] method.<ref>{{cite web|url=http://www.msm.cam.ac.uk/phase-trans/2005/Amir/bond.html |title=Diffusion Bonding of Materials |last=Kazakov |first=N.F |year=1985 |publisher=University of Cambridge |accessdate=2011-01-13 |deadurl=yes |archiveurl=http://www.webcitation.org/5nUYH5lQv?url=http://www.msm.cam.ac.uk/phase-trans/2005/Amir/bond.html |archivedate=2010-02-12 |df= }}</ref>

Other recent developments in welding include the 1958 breakthrough of electron beam welding, making deep and narrow welding possible through the concentrated heat source. Following the invention of the laser in 1960, laser beam welding debuted several decades later, and has proved to be especially useful in high-speed, automated welding. [[Magnetic pulse welding]] (MPW) is industrially used since 1967. [[Friction stir welding]] was invented in 1991 by Wayne Thomas at [[The Welding Institute]] (TWI, UK) and found high-quality applications all over the world.<ref>{{cite book|author=Mel Schwartz|title=Innovations in Materials Manufacturing, Fabrication, and Environmental Safety|url=https://books.google.com/books?id=rpCs0AoQOBoC&pg=PA300|accessdate=10 July 2012|date=2011|publisher=CRC Press|isbn=978-1-4200-8215-9|pages=300–}}</ref> All of these four new processes continue to be quite expensive due the high cost of the necessary equipment, and this has limited their applications.<ref>Lincoln Electric, pp. 1.1–10</ref>

==Processes==

===Arc===
{{Main article|Arc welding}}
[[File:Man welding a metal structure in a newly constructed house in Bengaluru, India.webm|thumb|Man welding a metal structure in a newly constructed house in Bengaluru, India]]
These processes use a [[welding power supply]] to create and maintain an electric arc between an electrode and the base material to melt metals at the welding point. They can use either [[direct current|direct]] (DC) or alternating (AC) current, and consumable or non-consumable [[electrode]]s. The welding region is sometimes protected by some type of inert or semi-[[inert gas]], known as a shielding gas, and filler material is sometimes used as well.

====Power supplies====
To supply the electrical power necessary for arc welding processes, a variety of different power supplies can be used. The most common welding power supplies are constant [[electrical current|current]] power supplies and constant [[voltage]] power supplies. In arc welding, the length of the arc is directly related to the voltage, and the amount of heat input is related to the current. Constant current power supplies are most often used for manual welding processes such as gas tungsten arc welding and shielded metal arc welding, because they maintain a relatively constant current even as the voltage varies. This is important because in manual welding, it can be difficult to hold the electrode perfectly steady, and as a result, the arc length and thus voltage tend to fluctuate. Constant voltage power supplies hold the voltage constant and vary the current, and as a result, are most often used for automated welding processes such as gas metal arc welding, flux cored arc welding, and submerged arc welding. In these processes, arc length is kept constant, since any fluctuation in the distance between the wire and the base material is quickly rectified by a large change in current. For example, if the wire and the base material get too close, the current will rapidly increase, which in turn causes the heat to increase and the tip of the wire to melt, returning it to its original separation distance.<ref>{{harvnb|Cary|Helzer|2005|pp=246–249}}</ref>

The type of current used plays an important role in arc welding. Consumable electrode processes such as shielded metal arc welding and gas metal arc welding generally use direct current, but the electrode can be charged either positively or negatively. In welding, the positively charged [[anode]] will have a greater heat concentration, and as a result, changing the polarity of the electrode affects weld properties. If the electrode is positively charged, the base metal will be hotter, increasing weld penetration and welding speed. Alternatively, a negatively charged electrode results in more shallow welds.<ref>Kalpakjian and Schmid, p. 780</ref> Nonconsumable electrode processes, such as gas tungsten arc welding, can use either type of direct current, as well as alternating current. However, with direct current, because the electrode only creates the arc and does not provide filler material, a positively charged electrode causes shallow welds, while a negatively charged electrode makes deeper welds.<ref>Lincoln Electric, p. 5.4–5</ref> Alternating current rapidly moves between these two, resulting in medium-penetration welds. One disadvantage of AC, the fact that the arc must be re-ignited after every zero crossing, has been addressed with the invention of special power units that produce a [[square wave]] pattern instead of the normal [[sine wave]], making rapid zero crossings possible and minimizing the effects of the problem.<ref>Weman, p. 16</ref>

====Processes====
One of the most common types of arc welding is [[shielded metal arc welding]] (SMAW);<ref name="Weman63">Weman, p. 63</ref> it is also known as manual metal arc welding (MMA) or stick welding. Electric current is used to strike an arc between the base material and consumable electrode rod, which is made of filler material (typically steel) and is covered with a flux that protects the weld area from [[redox|oxidation]] and contamination by producing [[carbon dioxide]] (CO2) gas during the welding process. The electrode core itself acts as filler material, making a separate filler unnecessary.<ref name="Weman63" />

[[Image:US Navy 090114-N-9704L-004 Hull Technician Fireman John Hansen lays beads for welding qualifications.jpg|thumb|left|Shielded metal arc welding]]

The process is versatile and can be performed with relatively inexpensive equipment, making it well suited to shop jobs and field work.<ref name="Weman63" /><ref name="Cary103">{{harvnb|Cary|Helzer|2005|p=103}}</ref> An operator can become reasonably proficient with a modest amount of training and can achieve mastery with experience. Weld times are rather slow, since the consumable electrodes must be frequently replaced and because slag, the residue from the flux, must be chipped away after welding.<ref name="Weman63" /> Furthermore, the process is generally limited to welding ferrous materials, though special electrodes have made possible the welding of [[cast iron]], [[nickel]], aluminum, [[copper]], and other metals.<ref name="Cary103" />
[[Image:SMAW area diagram.svg|thumb|right|Diagram of arc and weld area, in shielded metal arc welding.
 
1. Coating Flow 
2. Rod 
3. Shield Gas 
4. Fusion 
5. Base metal 
6. Weld metal 
7. Solidified Slag
]]

[[Gas metal arc welding]] (GMAW), also known as metal inert gas or MIG welding, is a semi-automatic or automatic process that uses a continuous wire feed as an electrode and an inert or semi-inert gas mixture to protect the weld from contamination. Since the electrode is continuous, welding speeds are greater for GMAW than for SMAW.<ref name="LE5.43">Lincoln Electric, p. 5.4-3</ref>

A related process, [[flux-cored arc welding]] (FCAW), uses similar equipment but uses wire consisting of a steel electrode surrounding a powder fill material. This cored wire is more expensive than the standard solid wire and can generate fumes and/or slag, but it permits even higher welding speed and greater metal penetration.<ref>Weman, p. 53</ref>

[[Gas tungsten arc welding]] (GTAW), or tungsten inert gas (TIG) welding, is a manual welding process that uses a nonconsumable [[tungsten]] electrode, an inert or semi-inert gas mixture, and a separate filler material.<ref name="Weman31">Weman, p. 31</ref> Especially useful for welding thin materials, this method is characterized by a stable arc and high quality welds, but it requires significant operator skill and can only be accomplished at relatively low speeds.<ref name="Weman31" />

GTAW can be used on nearly all weldable metals, though it is most often applied to [[stainless steel]] and light metals. It is often used when quality welds are extremely important, such as in [[bicycle]], aircraft and naval applications.<ref name="Weman31" /> A related process, plasma arc welding, also uses a tungsten electrode but uses plasma gas to make the arc. The arc is more concentrated than the GTAW arc, making transverse control more critical and thus generally restricting the technique to a mechanized process. Because of its stable current, the method can be used on a wider range of material thicknesses than can the GTAW process and it is much faster. It can be applied to all of the same materials as GTAW except magnesium, and automated welding of stainless steel is one important application of the process. A variation of the process is [[plasma cutting]], an efficient steel cutting process.<ref>Weman, pp. 37–38</ref>

[[Submerged arc welding]] (SAW) is a high-productivity welding method in which the arc is struck beneath a covering layer of flux. This increases arc quality, since contaminants in the atmosphere are blocked by the flux. The slag that forms on the weld generally comes off by itself, and combined with the use of a continuous wire feed, the weld deposition rate is high. Working conditions are much improved over other arc welding processes, since the flux hides the arc and almost no smoke is produced. The process is commonly used in industry, especially for large products and in the manufacture of welded pressure vessels.<ref>Weman, p. 68</ref> Other arc welding processes include [[atomic hydrogen welding]], [[electroslag welding]], [[electrogas welding]], and [[stud arc welding]].<ref>Weman, pp. 93–94</ref>

===Gas welding===
{{main article|Oxy-fuel welding and cutting}}

The most common gas welding process is oxyfuel welding,<ref name="Weman26" /> also known as oxyacetylene welding. It is one of the oldest and most versatile welding processes, but in recent years it has become less popular in industrial applications. It is still widely used for welding pipes and tubes, as well as repair work.<ref name="Weman26" />

The equipment is relatively inexpensive and simple, generally employing the combustion of acetylene in [[oxygen]] to produce a welding flame temperature of about 3100 °C.<ref name="Weman26" /> The flame, since it is less concentrated than an electric arc, causes slower weld cooling, which can lead to greater residual stresses and weld distortion, though it eases the welding of high alloy steels. A similar process, generally called oxyfuel cutting, is used to cut metals.<ref name="Weman26" />

===Resistance===
{{Main article|Resistance welding}}

Resistance welding involves the generation of heat by passing current through the resistance caused by the contact between two or more metal surfaces. Small pools of molten metal are formed at the weld area as high current (1000–100,000 [[Ampere|A]]) is passed through the metal.<ref name="Weman8084">Weman, pp. 80–84</ref> In general, resistance welding methods are efficient and cause little pollution, but their applications are somewhat limited and the equipment cost can be high.<ref name="Weman8084" />

[[Image:Spot welder.miller.triddle.jpg|thumb|Spot welder]]
[[Spot welding]] is a popular resistance welding method used to join overlapping metal sheets of up to 3 mm thick.<ref name="Weman8084" /> Two electrodes are simultaneously used to clamp the metal sheets together and to pass current through the sheets. The advantages of the method include [[efficient energy use]], limited workpiece deformation, high production rates, easy automation, and no required filler materials. Weld strength is significantly lower than with other welding methods, making the process suitable for only certain applications. It is used extensively in the automotive industry—ordinary cars can have several thousand spot welds made by [[industrial robot]]s. A specialized process, called [[shot welding]], can be used to spot weld stainless steel.<ref name="Weman8084" />

Like spot welding, [[seam welding]] relies on two electrodes to apply pressure and current to join metal sheets. However, instead of pointed electrodes, wheel-shaped electrodes roll along and often feed the workpiece, making it possible to make long continuous welds. In the past, this process was used in the manufacture of beverage cans, but now its uses are more limited.<ref name="Weman8084" /> Other resistance welding methods include [[butt welding]],<ref>{{Cite book|author = John Jernberg| title = Forging| page = 26| publisher = American Technical society| year = 1919| url = https://books.google.com/books?id=-ksxAAAAMAAJ&pg=PA26}}</ref> [[flash welding]], [[projection welding]], and [[upset welding]].<ref name="Weman8084" />

===Energy beam===
Energy beam welding methods, namely [[laser beam welding]] and [[electron beam welding]], are relatively new processes that have become quite popular in high production applications. The two processes are quite similar, differing most notably in their source of power. Laser beam welding employs a highly focused laser beam, while electron beam welding is done in a vacuum and uses an electron beam. Both have a very high energy density, making deep weld penetration possible and minimizing the size of the weld area. Both processes are extremely fast, and are easily automated, making them highly productive. The primary disadvantages are their very high equipment costs (though these are decreasing) and a susceptibility to thermal cracking. Developments in this area include [[laser-hybrid welding]], which uses principles from both laser beam welding and arc welding for even better weld properties, [[cladding (metalworking)|laser cladding]], and [[x-ray welding]].<ref>Weman, pp. 95–101</ref>

===Solid-state===
[[File:Solid-state welding processes - AWS A3.0 2001.svg|thumb|300px|right|Solid-state welding processes [[classification chart]]<ref>AWS A3.0:2001, Standard Welding Terms and Definitions Including Terms for Adhesive Bonding, Brazing, Soldering, Thermal Cutting, and Thermal Spraying, American Welding Society (2001), p. 117. {{ISBN|0-87171-624-0}}</ref>]]
Like the first welding process, forge welding, some modern welding methods do not involve the melting of the materials being joined. One of the most popular, [[ultrasonic welding]], is used to connect thin sheets or wires made of metal or thermoplastic by vibrating them at high frequency and under high pressure.<ref name="Weman8990">Weman, pp. 89–90</ref> The equipment and methods involved are similar to that of resistance welding, but instead of electric current, vibration provides energy input. Welding metals with this process does not involve melting the materials; instead, the weld is formed by introducing mechanical vibrations horizontally under pressure. When welding plastics, the materials should have similar melting temperatures, and the vibrations are introduced vertically. Ultrasonic welding is commonly used for making electrical connections out of aluminum or copper, and it is also a very common polymer welding process.<ref name="Weman8990" />

Another common process, [[explosion welding]], involves the joining of materials by pushing them together under extremely high pressure. The energy from the impact plasticizes the materials, forming a weld, even though only a limited amount of heat is generated. The process is commonly used for welding dissimilar materials, such as the welding of aluminum with steel in ship hulls or compound plates.<ref name="Weman8990" /> Other solid-state welding processes include [[friction welding]] (including [[friction stir welding]]),<ref name="NZ">Stephan Kallee (August 2006) [http://www.twi.co.uk/content/spswkaug2006.html "NZ Fabricators begin to use Friction Stir Welding to produce aluminium components and panels"] {{webarchive |url=https://web.archive.org/web/20100316134257/http://www.twi.co.uk/content/spswkaug2006.html |date=March 16, 2010 }}. ''New Zealand Engineering News''.</ref> [[magnetic pulse welding]],<ref name="EMPT">Stephan Kallee et al. (2010) ''[http://www.msm.cam.ac.uk/phase-trans/2010/IPM.pdf Industrialisation of Electromagnetic Pulse Technology (EMPT) in India]'' 38th Anniversary Issue of PURCHASE India.</ref> co-extrusion welding, [[cold welding]], [[diffusion bonding]], [[exothermic welding]], [[high frequency welding]], hot pressure welding, [[induction welding]], and [[Cladding (metalworking)|roll welding]].<ref name="Weman8990" />

Welds can be geometrically prepared in many different ways. The five basic types of weld joints are the butt joint, lap joint, corner joint, edge joint, and T-joint (a variant of this last is the [[cruciform joint]]). Other variations exist as well—for example, double-V preparation joints are characterized by the two pieces of material each tapering to a single center point at one-half their height. Single-U and double-U preparation joints are also fairly common—instead of having straight edges like the single-V and double-V preparation joints, they are curved, forming the shape of a U. Lap joints are also commonly more than two pieces thick—depending on the process used and the thickness of the material, many pieces can be welded together in a lap joint geometry.<ref>{{Cite book
| last = Hicks
| first = John
| year = 1999
| title = Welded Joint Design
| location = [[New York City|New York]]
| publisher = Industrial Press
| isbn = 0-8311-3130-6 | pages=52–55
}}</ref>

Many welding processes require the use of a particular joint design; for example, resistance spot welding, laser beam welding, and electron beam welding are most frequently performed on lap joints. Other welding methods, like shielded metal arc welding, are extremely versatile and can weld virtually any type of joint. Some processes can also be used to make multipass welds, in which one weld is allowed to cool, and then another weld is performed on top of it. This allows for the welding of thick sections arranged in a single-V preparation joint, for example.<ref>{{harvnb|Cary|Helzer|2005|pp=19, 103, 206}}</ref>

[[Image:Welded butt joint x-section.svg|thumb|The cross-section of a welded butt joint, with the darkest gray representing the weld or fusion zone, the medium gray the heat-affected zone, and the lightest gray the base material.]]
After welding, a number of distinct regions can be identified in the weld area. The weld itself is called the fusion zone—more specifically, it is where the filler metal was laid during the welding process. The properties of the fusion zone depend primarily on the filler metal used, and its compatibility with the base materials. It is surrounded by the [[heat-affected zone]], the area that had its microstructure and properties altered by the weld. These properties depend on the base material's behavior when subjected to heat. The metal in this area is often weaker than both the base material and the fusion zone, and is also where residual stresses are found.<ref>{{harvnb|Cary|Helzer|2005|pp=401–404}}</ref>

==Quality==
{{main article|Weld quality assurance}}
[[Image:Pipe root weld with HAZ.jpg|thumb|The blue area results from oxidation at a corresponding temperature of {{convert|600|°F|°C|abbr=on}}. This is an accurate way to identify temperature, but does not represent the HAZ width. The HAZ is the narrow area that immediately surrounds the welded base metal.]]

Many distinct factors influence the strength of welds and the material around them, including the welding method, the amount and concentration of energy input, the [[weldability]] of the base material, filler material, and flux material, the design of the joint, and the interactions between all these factors.<ref name="Weman6062">Weman, pp. 60–62</ref> To test the quality of a weld, either [[destructive testing|destructive]] or [[nondestructive testing]] methods are commonly used to verify that welds are free of defects, have acceptable levels of residual stresses and distortion, and have acceptable heat-affected zone (HAZ) properties. Types of [[welding defect]]s include cracks, distortion, gas inclusions (porosity), non-metallic inclusions, lack of fusion, incomplete penetration, lamellar tearing, and undercutting.

The metalworking industry has instituted [[List of welding codes|specifications and codes]] to guide [[welders]], [[weld inspectors]], [[engineers]], managers, and property owners in proper welding technique, design of welds, how to judge the quality of [[Welding Procedure Specification]], how to judge the skill of the person performing the weld, and how to ensure the quality of a welding job.<ref name="Weman6062" /> Methods such as [[visual inspection]], [[radiography]], [[ultrasonic testing]], [[phased-array ultrasonics]], [[dye penetrant inspection]], [[magnetic particle inspection]], or [[industrial computed tomography]] can help with detection and analysis of certain defects.

===Heat-affected zone===
The heat-affected zone (HAZ) is a ring surrounding the weld in which the temperature of the welding process, combined with the stresses of uneven heating and cooling, alter the [[heat-treatment]] properties of the alloy. The effects of welding on the material surrounding the weld can be detrimental—depending on the materials used and the heat input of the welding process used, the HAZ can be of varying size and strength. The [[thermal diffusivity]] of the base material plays a large role—if the diffusivity is high, the material cooling rate is high and the HAZ is relatively small. Conversely, a low diffusivity leads to slower cooling and a larger HAZ. The amount of heat injected by the welding process plays an important role as well, as processes like oxyacetylene welding have an unconcentrated heat input and increase the size of the HAZ. Processes like laser beam welding give a highly concentrated, limited amount of heat, resulting in a small HAZ. Arc welding falls between these two extremes, with the individual processes varying somewhat in heat input.<ref>Lincoln Electric, pp. 6.1-5–6.1–6</ref><ref>Kalpakjian and Schmid, pp. 821–22</ref> To calculate the heat input for arc welding procedures, the following formula can be used:

:<math>Q = \left(\frac{V \times I \times 60}{S \times 1000} \right) \times
\mathit{Efficiency}</math>

where ''Q'' = heat input ([[kilojoule|kJ]]/mm), ''V'' = voltage ([[Volt|V]]), ''I'' = current (A), and ''S'' = welding speed (mm/min). The efficiency is dependent on the welding process used, with shielded metal arc welding having a value of 0.75, gas metal arc welding and submerged arc welding, 0.9, and gas tungsten arc welding, 0.8.<ref>Weman, p. 5</ref> Methods of alleviating the stresses and brittleness created in the HAZ include [[Heat treating#Stress relieving|stress relieving]] and [[Tempering (metallurgy)#Welded steel|tempering]].<ref>''How To Weld'' By Todd Bridigum - Motorbook 2008 Page 37</ref>

===Lifetime extension with aftertreatment methods===
[[Image:Example HiFIT-treated assembly.jpg|thumb|left|Example: High Frequency Impact Treatment for lifetime extension]]
The durability and life of dynamically loaded, welded steel structures is determined in many cases by the welds, in particular the weld transitions. Through selective treatment of the transitions by [[grinding (abrasive cutting)]], [[shot peening]], [[High Frequency Impact Treatment]], etc. the durability of many designs increase significantly.

==Unusual conditions==
[[File:Working Diver 01.jpg|thumb|left|Underwater welding]]

While many welding applications are done in controlled environments such as factories and repair shops, some welding processes are commonly used in a wide variety of conditions, such as open air, underwater, and [[vacuum]]s (such as space). In open-air applications, such as construction and outdoors repair, shielded metal arc welding is the most common process. Processes that employ inert gases to protect the weld cannot be readily used in such situations, because unpredictable atmospheric movements can result in a faulty weld. Shielded metal arc welding is also often used in underwater welding in the construction and repair of ships, offshore platforms, and pipelines, but others, such as flux cored arc welding and gas tungsten arc welding, are also common. Welding in space is also possible—it was first attempted in 1969 by [[Russia]]n cosmonauts, when they performed experiments to test shielded metal arc welding, plasma arc welding, and electron beam welding in a depressurized environment. Further testing of these methods was done in the following decades, and today researchers continue to develop methods for using other welding processes in space, such as laser beam welding, resistance welding, and friction welding. Advances in these areas may be useful for future endeavours similar to the construction of the [[International Space Station]], which could rely on welding for joining in space the parts that were manufactured on Earth.<ref>{{harvnb|Cary|Helzer|2005|pp=677–683}}</ref>

==Glass and plastic welding==
[[File:Glass welding two tubes together.JPG|thumb|The welding together of two tubes made from lead glass]]
[[File:Cast glass bowl showing the weld seam.JPG|thumb|A bowl made from cast-glass. The two halves are joined together by the weld seam, running down the middle.]]

Glasses and certain types of plastics are commonly welded materials. Unlike metals, which have a specific [[melting point]], glasses and plastics have a melting range, called the [[glass transition]]. When heating the solid material into this range, it will generally become softer and more pliable. When it crosses through the glass transition, it will become a very thick, sluggish, viscous liquid. Typically, this [[viscous liquid]] will have very little [[surface tension]], becoming a sticky, honey-like consistency, so welding can usually take place by simply pressing two melted surfaces together. The two liquids will generally mix and join at first contact. Upon cooling through the glass transition, the welded piece will solidify as one solid piece of [[amorphous solid|amorphous material]].

===Glass welding===
{{main article|Glassblowing}}

Glass welding is a common practice during glassblowing. It is used very often in the construction of lighting, [[neon sign]]s, [[flashtube]]s, scientific equipment, and the manufacture of dishes and other glassware. It is also used during [[glass casting]] for joining the halves of glass molds, making items such as bottles and jars. Welding glass is accomplished by heating the glass through the glass transition, turning it into a thick, formable, liquid mass. Heating is usually done with a gas or oxy-gas torch, or a furnace, because the temperatures for melting glass are often quite high. This temperature may vary, depending on the type of glass. For example, [[lead glass]] becomes a weldable liquid at around {{convert|1600|F|C}}, and can be welded with a simple propane torch. On the other hand, quartz glass ([[fused silica]]) must be heated to over {{convert|3000|F|C}}, but quickly loses its viscosity and formability if overheated, so an [[oxyhydrogen]] torch must be used. Sometimes a tube may be attached to the glass, allowing it to be blown into various shapes, such as bulbs, bottles, or tubes. When two pieces of liquid glass are pressed together, they will usually weld very readily. Welding a handle onto a pitcher can usually be done with relative ease. However, when welding a tube to another tube, a combination of blowing and suction, and pressing and pulling is used to ensure a good seal, to shape the glass, and to keep the surface tension from closing the tube in on itself. Sometimes a filler rod may be used, but usually not.

Because glass is very brittle in its solid state, it is often prone to cracking upon heating and cooling, especially if the heating and cooling are uneven. This is because the brittleness of glass does not allow for uneven [[thermal expansion]]. Glass that has been welded will usually need to be cooled very slowly and evenly through the glass transition, in a process called [[annealing (glass)|annealing]], to relieve any internal stresses created by a [[temperature gradient]].

There are many types of glass, and it is most common to weld using the same types. Different glasses often have different rates of thermal expansion, which can cause them to crack upon cooling when they contract differently. For instance, quartz has very low thermal expansion, while [[soda-lime glass]] has very high thermal expansion. When welding different glasses to each other, it is usually important to closely match their coefficients of thermal expansion, to ensure that cracking does not occur. Also, some glasses will simply not mix with others, so welding between certain types may not be possible.

Glass can also be welded to metals and ceramics, although with metals the process is usually more adhesion to the surface of the metal rather than a commingling of the two materials. However, certain glasses will typically bond only to certain metals. For example, lead glass bonds readily to [[copper]] or [[molybdenum]], but not to aluminum. [[Tungsten]] electrodes are often used in lighting but will not bond to quartz glass, so the tungsten is often wetted with molten [[borosilicate glass]], which bonds to both tungsten and quartz. However, care must be taken to ensure that all materials have similar coefficients of thermal expansion to prevent cracking both when the object cools and when it is heated again. Special [[alloy]]s are often used for this purpose, ensuring that the coefficients of expansion match, and sometimes thin, metallic coatings may be applied to a metal to create a good bond with the glass.<ref>Freek Bos, Christian Louter, Fred Veer (2008) ''Challenging Glass: Conference on Architectural and Structural Applications''. JOS Press. p. 194. {{ISBN|1586038664}}</ref><ref>Bernard D. Bolas (1921) [https://archive.org/details/handbookoflabora02bolarich ''A handbook of laboratory glassblowing'']. London, G. Routledge and sons</ref>

===Plastic welding===
{{main article|Plastic welding}}

Plastics are generally divided into two categories, which are "thermosets" and "thermoplastics." A [[thermoset]] is a plastic in which a chemical reaction sets the molecular bonds after first forming the plastic, and then the bonds cannot be broken again without degrading the plastic. Thermosets cannot be melted, therefore, once a thermoset has set it is impossible to weld it. Examples of thermosets include [[epoxy|epoxies]], [[silicone]], [[vulcanized rubber]], [[polyester]], and [[polyurethane]].

[[Thermoplastic]]s, by contrast, form long molecular chains, which are often coiled or intertwined, forming an amorphous structure without any long-range, crystalline order. Some thermoplastics may be fully amorphous, while others have a partially crystalline/partially amorphous structure. Both amorphous and semicrystalline thermoplastics have a glass transition, above which welding can occur, but semicrystallines also have a specific melting point which is above the glass transition. Above this melting point, the viscous liquid will become a free-flowing liquid (see [[rheological weldability]] for [[thermoplastics]]). Examples of thermoplastics include [[polyethylene]], [[polypropylene]], [[polystyrene]], [[polyvinylchloride]] (PVC), and fluoroplastics like [[Teflon]] and [[Spectralon]].

Welding thermoplastic is very similar to welding glass. The plastic first must be cleaned and then heated through the glass transition, turning the weld-interface into a thick, viscous liquid. Two heated interfaces can then be pressed together, allowing the molecules to mix through intermolecular diffusion, joining them as one. Then the plastic is cooled through the glass transition, allowing the weld to solidify. A filler rod may often be used for certain types of joints. The main differences between welding glass and plastic are the types of heating methods, the much lower melting temperatures, and the fact that plastics will burn if overheated. Many different methods have been devised for heating plastic to a weldable temperature without burning it. Ovens or electric heating tools can be used to melt the plastic. Ultrasonic, laser, or friction heating are other methods. Resistive metals may be implanted in the plastic, which respond to induction heating. Some plastics will begin to burn at temperatures lower than their glass transition, so welding can be performed by blowing a heated, inert gas onto the plastic, melting it while, at the same time, shielding it from oxygen.<ref>''Plastics and Composites: Welding Handbook'' By David A. Grewell, A. Benatar, Joon Bu Park – Hanser Gardener 2003</ref>

Many thermoplastics can also be welded using chemical [[solvent]]s. When placed in contact with the plastic, the solvent will begin to soften it, bringing the surface into a thick, liquid solution. When two melted surfaces are pressed together, the molecules in the solution mix, joining them as one. Because the solvent can permeate the plastic, the solvent evaporates out through the surface of the plastic, causing the weld to drop out of solution and solidify. A common use for solvent welding is for joining PVC or ABS ([[acrylonitrile butadiene styrene]]) pipes during [[plumbing]], or for welding [[styrene]] and polystyrene plastics in the construction of [[physical model|models]]. Solvent welding is especially effective on plastics like PVC which burn at or below their glass transition, but may be ineffective on plastics like Teflon or polyethylene that are resistant to [[chemical decomposition]].<ref>''Handbook of Plastics Joining: A Practical Guide'' By Plastics Design Library – PDL 1997 Page 137, 146</ref>

== Usage in competitive ==
{{Metalworks/MapLeagueInclusionTable}}
== Locations ==

{{Map locations
| title = Metalworks — The middle point
| image = Metalworks Middle.jpeg
| area1 = Valley
| x1 = 218px
| y1 = 170px
| area2 = Lower Lobby / Main
| x2 = 316px
| y2 = 130px
| area3 = Elbow / Banana
| x3 = 454px
| y3 = 90px
| area4 = Point
| x4 = 430px
| y4 = 180px
| area5 = Crate
| x5 = 596px
| y5 = 150px
| area6 = Upper larry / Balcony
| x6 = 527px
| y6 = 330px
| area7 = Truck
| x7 = 700px
| y7 = 182px
}}

{{Map locations
| title = Metalworks — The second point
| image = Metalworks Second.jpeg
| area1 = Underpass / Ground
| x1 = 390px
| y1 = 170px
| area2 = Alleyway
| x2 = 637px
| y2 = 200px
| area3 = Main / Metal
| x3 = 388px
| y3 = 125px
| area4 = Point
| x4 = 283px
| y4 = 244px
| area5 = Bridge
| x5 = 247px
| y5 = 179px
}}

{{Map locations
| title = Metalworks — The last point
| image = Metalworks Last.jpeg
| area1 = Far Left
| x1 = 131px
| y1 = 170px
| area2 = Shed
| x2 = 177px
| y2 = 121px
| area3 = Shutter
| x3 = 330px
| y3 = 80px
| area4 = Main
| x4 = 402px
| y4 = 68px
| area5 = Far Right
| x5 = 612px
| y5 = 102px
}}

== References ==
{{reflist}}

{{Active Maps Navbox}}{{All Maps Navbox|y}}

Granary Pro

2017-08-09T21:13:05Z

81.147.69.112:

{{stub}}
{{NewInfobox Map
|name=
|image=
|caption=

|maptype=5cp
|filename=cp_granary_pro_rc8
|version=Release Candidate 5
|author1=Jon "Dagger"
|author1steam=76561198062441527
|author2=
|author2steam=
|author3=
|author3steam=
|released=17 March 2015
|updated=20 February 2017
|official=

|gamemode1=6v6
|gamemode2=
|gamemode3=
|adapted=Granary
|pro=
|popularity=moderate
|lpleague=
|lpseason=

|download=http://fakkelbrigade.eu/maps/cp_granary_pro_rc5.bsp.bz2
|workshop=468558173
|tf2maps=
|gamebanana=
|tftv=23574
|tftv2=
|etf2l=
|ugc=
|officialwiki=
|officialwiki2=

|footnotes=
}}
'''cp_granary_pro''' is a [[5CP]] map, created from the basis of [[cp_granary]], which was originally created by Valve.

''Some of the tactics written on the default cp_granary may be applicable to this map.''

== History ==
A '''granary''' is a storehouse or room in a [[barn]] for [[threshing|threshed]] [[cereal|grain]] or [[compound feed|animal feed]]. Ancient or primitive granaries are most often made out of [[pottery]]. Granaries are often built above the ground to keep the stored food away from mice and other animals.

==Early origins==
From ancient times grain has been stored in bulk. The oldest granaries yet found date back to [[10th millennium BC|9500 BC]]<ref name="PNAS09">{{Cite journal | date=Jun 2009 | pages = 10966–10970| issn = 0027-8424| last1 = Kuijt | doi = 10.1073/pnas.0812764106 | pmc = 2700141 | pmid = 19549877| issue = 27 | volume = 106 | title = Evidence for food storage and predomestication granaries 11,000 years ago in the Jordan Valley | first2 = B.| url = http://www.pnas.org/cgi/pmidlookup?view=long&pmid=19549877 | format = Free full text | journal = Proceedings of the National Academy of Sciences of the United States of America| last2 = Finlayson| first1 = I.|bibcode = 2009PNAS..10610966K }}</ref> and are located in the [[Pre-Pottery Neolithic A]] settlements in the [[Jordan River|Jordan Valley]]. The first were located in places between other buildings. However beginning around [[9th millennium BC|8500 BC]], they were moved inside houses, and by [[8th millennium BC|7500 BC]] storage occurred in special rooms.<ref name="PNAS09"/> The first granaries measured 3 x 3 m on the outside and had suspended floors that protected the grain from rodents and insects and provided air circulation.<ref name="PNAS09"/>

In the latest development of Granary Pro, changes in favour of competitive gameplay included expanding mid, removing props, raising the ceiling in choke and moving forward spawns backwards.

These granaries are followed by those in [[Mehrgarh]] in the [[Indus Valley]] from 6000 BC. The [[ancient Egypt]]ians made a practice of preserving grain in years of plenty against years of scarcity. The climate of Egypt being very dry, grain could be stored in pits for a long time without discernible loss of quality. The silo pit, as it has been termed, has been a favorite way of storing grain from time immemorial in all oriental lands{{clarifyme|date=May 2016}}. In Turkey and Persia, [[usurer]]s used to buy up [[wheat]] or [[barley]] when comparatively cheap, and store it in hidden pits against seasons of dearth. In Malta a relatively large stock of wheat was preserved in some hundreds of pits (silos) cut in the rock. A single silo stored from 60 to 80 tons of wheat, which, with proper precautions, kept in good condition for four years or more.

==East Asia==
[[File:Han Dynasty Granary west of Dunhuang.jpg|thumb|300px|[[Han dynasty]] granary on [[Silk Road]] west of [[Dunhuang]]]]
Simple storage granaries raised up on four or more posts appeared in the [[Yangshao culture]] in China and after the onset of intensive agriculture in the Korean peninsula during the [[Mumun pottery period]] (c. 1000 B.C.) as well as in the Japanese archipelago during the Final [[Jōmon]]/Early [[Yayoi period]]s (c. 800 B.C.). In the archaeological vernacular of Northeast Asia, these features are lumped with those that may have also functioned as residences and together are called 'raised floor buildings'.

==Southeast Asia==
In [[Indonesian architecture|vernacular architecture]] of [[Indonesia|Indonesian archipelago]] granaries are made of wood and bamboo materials and most of them are built raised up on four or more posts to avoid rodents and insects. Examples of Indonesian granary is [[Sundanese people|Sundanese]] ''leuit'' and [[Minangkabau people|Minang]] ''[[rangkiang]]''.

==Great Britain==
In Great Britain small granaries were built on [[mushroom]] shaped stumps called [[staddle stones]]. They were built of timber frame construction and often had slate roofs. Larger ones were similar to [[linhay]]s, but with the upper floor enclosed. Access to the first floor was usually via stone staircase on the outside wall.<ref>http://www.southhams.gov.uk/index/business_index/ksp_development_and_planning/ksp-development_and_planning-conservation/sp-development_and_planning-barnguide.htm The Barn Guide by South Hams District Council</ref>

Towards the close of the 19th century, warehouses specially intended for holding grain began to multiply in Great Britain. There are climatic difficulties in the way of storing grain in Great Britain on a large scale, but these difficulties have been largely overcome.

==Modern==
[[File:Shelby County, Iowa. These granaries are located near Irwin Village, and much of the corn which is n . . . - NARA - 522350.jpg|thumb|Modern steel granaries in the United States]]
Modern grain farming operations often use manufactured steel granaries to store grain on-site until it can be trucked to major storage facilities in anticipation of shipping. The large ''mechanized'' facilities, particularly seen in Russia and North America are known as [[grain elevator]]s.
[[File:Port Perry grain mill and elevator circa 1930.jpg|thumb|The Port Perry mill and grain elevator, granary circa 1930. Originally built in 1873, the building remains a major landmark to this day as the oldest in Canada. The original line of the PW&PP Railway can be seen in the foreground.]]

== Moisture control ==
Grain must be kept away from moisture for as long as possible to preserve it in good condition and prevent [[molds|mold growth]]. Newly harvested grain brought into a granary tends to contain excess moisture, which encourages mold growth leading to fermentation and heating, both of which are undesirable and affect quality. Fermentation generally spoils grain and may cause chemical changes that create poisonous [[mycotoxins]].

One traditional remedy is to spread the grain in thin layers on a floor, where it is turned to aerate it thoroughly. Once the grain is sufficiently dry it can be transferred to a granary for storage. A modern variation on this, is to use a grain auger to move grain stored in one grainery to another.

In modern silos, grain is typically force-aerated ''in situ'' or circulated through external [[grain drying]] equipment.

== Usage in competitive ==
{{Granary Pro/MapLeagueInclusionTable}}
== Map Locations ==
=== Middle point ===
{{Map locations
| title = Granary Pro — The middle point
| image = Granary Pro Middle.jpeg
| area1 = Garage | x1 = 309px | y1 = 72px
| area2 = Choke | x2 = 620px | y2 = 40px
| area3 = Balcony / Catwalk | x3 = 479px | y3 = 14px
| area4 = Top left (crate) / 2 | x4 = 308px | y4 = 118px
| area5 = Top right (crate) / 3 | x5 = 523px | y5 = 108px
| area6 = Back left (crate) / 1 | x6 = 246px | y6 = 230px
| area7 = Back right (crate) / 4 | x7 = 559px | y7 = 238px
| area8 = Far left | x8 = 177px | y8 = 277px
| area9 = Far right | x9 = 588px | y9 = 154px
}}

=== Second point ===
{{Map locations
| title = Granary Pro — The second point, yard
| image = Granary Pro Second Point 1.jpeg
| area1 = Choke | x1=142px | y1=4px
| area2 = Window | x2=338px | y2=21px
| area3 = Garage | x3=469px | y3=60px
| area4 = Left yard | x4=270px | y4=228px
| area5 = Right yard | x5=550px | y5=228px
}}
{{Map locations
| title = Granary Pro — The second point, left yard view
| image = Granary Pro Second Point 2.jpeg
| area1 = Dropdown | x1=627px | y1=128px
| area2 = Z | x2=282px | y2=197px
| area3 = To Stairs / Spiral / Lunchbox | x3=128px | y3=219px
| area4 = Garage | x4=772px | y4=220px
| area5 = Left yard | x5=258px | y5=250px
}}
{{Map locations
| title = Granary Pro — The second point, inside view
| image = Granary Pro Second Point 3.jpeg
| area1 = Dropdown | x1=88px | y1=70px
| area2 = Top | x2=113px | y2=170px
| area3 = Left | x3=100px | y3=264px
| area4 = Stairs / spiral | x4=317px | y4=285px
| area5 = Lunchbox | x5=580px | y5=356px
}}

=== Last point ===
{{Map locations
| title = Granary Pro — The last point
| image = Granary Pro Last Point.jpeg
| area1 = Top right / Window | x1=466px | y1=29px
| area2 = Top left | x2=342px | y2=38px
| area3 = Left | x3=254px | y3=63px
| area4 = Right | x4=493px | y4=98px
| area5 = Left yard | x5=225px | y5=164px
| area6 = Right yard | x6=551px | y6=171px
| area7 = Upper pipe | x7=439px | y7=194px
| area8 = Lower pipe | x8=324px | y8=223px
| area9 = Right spawn | x9=537px | y9=327px
| area10 = Left spawn | x10=225px | y10=343px
}}

== External Links ==
* [https://teamfortress.tv/thread/23574/cp-granary-pro TeamFortress.tv Thread]

{{Active Maps Navbox}}{{All Maps Navbox|y}}

Granary Pro

2017-08-09T21:11:13Z

81.147.69.112: /* Early origins */

Granary Pro

2017-08-09T21:10:47Z

81.147.69.112:

Granary Pro

2017-08-09T21:09:54Z

81.147.69.112:

Coalplant

2017-08-09T21:07:21Z

81.147.69.112:

Metalworks

2017-08-09T21:06:12Z

81.147.69.112:

Insomnia61

2017-08-09T20:59:46Z

81.147.69.112: /* Invite Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=$5,000,000
|date =
|sdate = 2016-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Wembley Arena, London, England from the 26th to the 29th of August 2017. A $5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEp!c |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=jp
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===
* {{flag|fi}} [https://www.twitch.tv/puoskaritf Puoskari]

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:55:46Z

81.147.69.112:

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=$5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Wembley Arena, London, England from the 26th to the 29th of August 2017. A $5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEpic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=jp
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===
* {{flag|fi}} [https://www.twitch.tv/puoskaritf Puoskari]

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:53:46Z

81.147.69.112: /* Additional content */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=$5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A $5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEpic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=jp
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===
* {{flag|fi}} [https://www.twitch.tv/puoskaritf Puoskari]

===Highlights===

== References ==
{{reflist}}

Silentes

2017-08-09T20:48:58Z

81.147.69.112:

Insomnia61

2017-08-09T20:47:25Z

81.147.69.112: /* Invite Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEpic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=jp
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:46:41Z

81.147.69.112: /* Invite Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=In
|scout2=Mr.JEpic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:45:27Z

81.147.69.112: /* Invite Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.JEpic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===

===Highlights===

== References ==
{{reflist}}

Silentes

2017-08-09T20:44:43Z

81.147.69.112:

Insomnia61

2017-08-09T20:40:13Z

81.147.69.112: /* Streams */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin MR SLIN]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:39:39Z

81.147.69.112: /* Streams */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=se
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|uk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]
* {{flag|us}} [https://www.twitch.tv/misterslin]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:32:44Z

81.147.69.112:

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Low Group Participants ==
Teams participating in the Low Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:31:47Z

81.147.69.112: /* Intermediate Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==
Teams participating in the Intermediate Group have not yet been announced.

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:31:10Z

81.147.69.112:

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Intermediate Group Participants ==

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:29:28Z

81.147.69.112:

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 26th to the 29th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 3,000,000|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 2,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 1,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0,000,000|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [https://www.twitch.tv/dreamhackcs WARHURYEAH.GG]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:24:08Z

81.147.69.112:

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Sunshine
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 25th to the 28th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 0|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [http://www.twitch.tv/essentialstf Essentials.TF]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:22:00Z

81.147.69.112:

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN (Local And Network)
|country = England
|city = Wembley Arena, London
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000,000
|date =
|sdate = 2017-08-26
|edate = 2017-08-29
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Prolands
|map2=Granary Pro
|map3=Bagel
|map4=Metalworks
|map5=Coalplant
|map6=Reckoner
|map7=Gravelpit
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 25th to the 28th of August 2017. A £5,000,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 0|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [http://www.twitch.tv/essentialstf Essentials.TF]

===VODs===

===Highlights===

== References ==
{{reflist}}

Insomnia61

2017-08-09T20:12:55Z

81.147.69.112: /* Invite Group Participants */

{{TabsHeader|name1=Overview|link1=Insomnia61/Overview
|name2=Main Event|link2=Insomnia61
|name3=Statistics|link3=Insomnia61/Statistics
|This=2
}}
{{DISPLAYTITLE:Insomnia61: Main Event}}
{{NewInfobox Season
|name= Insomnia61
|image=
|icon=Multiplayicon.png
|caption=
|series= Insomnia Gaming Festival
|organizer= [https://multiplay.com/ Multiplay]
|sponsor=
|gamemode= 6v6
|gamemode2=
|type = LAN
|country = England
|city = Birmingham
|venue = [http://www.thenec.co.uk/ NEC]
|format=
|prizepool=£5,000
|date =
|sdate = 2017-08-25
|edate = 2017-08-28
|totalteams =
|bestplayer =
|web= http://www.insomniagamingfestival.com/insomnia/whats-on/insomnia61-team-fortress-2-open/
|archive=http://archive.is/QOOWF
|brackets= |bracketscomment=Invite Group Stage
|brackets2= |brackets2comment=Playoffs
|teamfirst=
|teamsecond=
|teamthird=
|teamfourth=
|map1=Badlands
|map2=Granary Pro
|map3=Gullywash
|map4=Process
|map5=Product
|map6=Reckoner
|map7=Snakewater
|map8=
|map9=
|map10=
|map11=
|map12=
|map13=
|map14=
|map15=
|next=
|nextlabel=
|previous= Insomnia58
|previouslabel= i58
|footnotes=
}}
The '''Insomnia61 Team Fortress 2 Open''', commonly referred to as '''Insomnia61''' or simply '''i61''', is the successor to [[i58]] and part of the [[Insomnia Gaming Festival|Insomnia Gaming LAN Series]] hosted by [https://multiplay.com/ Multiplay]. The event will be held at [http://www.thenec.co.uk/ The NEC] in Birmingham, England from the 25th to the 28th of August 2017. An £5,000 prize pool is up for grabs.

== Prizes ==
{{prize pool start}}
{{prize pool slot|place=1|usdprize= 0|localprize = 0|tbd |lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=2|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=3|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{prize pool slot|place=4|usdprize= 0|localprize = 0|tbd|lastvs1= |lastscore1= |lastvsscore1= }}
{{Prize pool end}}

== Invite Group Participants ==

Not all teams participating in the Invite Group have been announced or confirmed yet.

{{Box|start|padding=2em}}
{{6sTeamCard
|team=Ascent
|image=AscentEsports.png
|scout1=corsa |scout1flag=us
|scout2=yomps |scout2flag=us
|roamer=rando |roamerflag=us
|pocket=Ma3la |pocketflag=us
|demoman=Bdonski |demomanflag=us
|medic=Nursey |medicflag=us
|notes=
}}
{{6sTeamCard
|team=Lowpander
|image=Lowpander.png
|scout1=Funs|scout1flag=wales
|scout2=Mr.Epic |scout2flag=ru
|roamer=Muuki |roamerflag=fi
|pocket=uubers |pocketflag=lv
|demoman=Hildreth |demomanflag=uken
|medic=Crayon|medicflag=ireland
|notes=
}}
{{Box|break|padding=2em}}
{{6sTeamCard
|team=Team SVIFT
|image=TeamSVIFT.jpg
|scout1=astt |scout1flag=fi
|scout2=SVMZI |scout2flag=de
|roamer=Silentes |roamerflag=en
|pocket=b4nny |pocketflag=us
|demoman=alle |demomanflag=se
|medic=Jim Vickers |medicflag=en
|notes=
}}
{{Box|end|padding=2em}}

== Open Group Participants ==

Teams participating in the Open Group have not yet been announced.

== Additional content ==
===Streams===
* {{flag|usuk}} [http://www.twitch.tv/essentialstf Essentials.TF]

===VODs===

===Highlights===

== References ==
{{reflist}}