Editing Advanced gas-cooled reactor (section)

==Existing AGR reactors==
As of August 2022, there are four nuclear generating stations each with two operating AGRs in the United Kingdom,<ref>{{cite web|title=United Kingdom of Great Britain and Northern Ireland: Nuclear Power Reactors |url=http://www.iaea.org/cgi-bin/db.page.pl/pris.powrea.htm?country=GB |date=22 May 2010 |work=PRIS database |publisher=International Atomic Energy Agency |access-date=22 May 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110628235010/http://www.iaea.org/cgi-bin/db.page.pl/pris.powrea.htm?country=GB |archive-date=28 June 2011 }}</ref> all of which are owned and operated by [[EDF Energy]]:

{| class="wikitable sortable"
|-
!AGR power<br />station !! Net<br />MWe !! Construction<br />started !! Connected<br />to grid !! Commercial<br />operation !! Accounting<br />closure date
|-
|[[Hartlepool nuclear power station|Hartlepool]]|| 1210 || 1968 
| rowspan="2" |1983|| rowspan="3" | 1989 || rowspan="2" | 2027
|-
|[[Heysham nuclear power station|Heysham 1]] || 1150 || 1970 
|-
|[[Heysham nuclear power station|Heysham 2]] || 1250 || 1980 || 1988 || rowspan="2" | 2030
|-
|[[Torness nuclear power station|Torness]] || 1250 || 1980 || colspan="2" | 1988
|}

In 2005 British Energy announced a 10-year life extension at Dungeness B, that would see the station continue operating until 2018,<ref>{{Cite journal|url=http://www.british-energy.com/article.php?article=99 |title=10-year life extension at Dungeness B nuclear power station|date=15 September 2005|publisher=[[British Energy]]|access-date=19 June 2008|archive-url = https://web.archive.org/web/20060322013831/http://www.british-energy.com/article.php?article=99 |archive-date = 22 March 2006}}</ref> and in 2007 announced a 5-year life extension of Hinkley Point B and Hunterston B until 2016.<ref name=BE-20071211>{{Cite journal|url=http://www.british-energy.co.uk/article.php?article=218 |archive-url=https://web.archive.org/web/20181001111408/http://www.british-energy.co.uk/article.php?article=218 |url-status=dead |archive-date=1 October 2018 |title=Life extension of Hinkley Point B and Hunterston B power stations |date=11 December 2007 |publisher=[[British Energy]] |access-date=19 June 2008 }}</ref> Life extensions at other AGRs will be considered at least three years before their scheduled closure dates.

From 2006 Hinkley Point B and Hunterston B have been restricted to about 70% of normal MWe output because of boiler-related problems requiring that they operate at reduced boiler temperatures.<ref name=BE-20071211 /> In 2013 these two stations' power increased to about 80% of normal output following some plant modifications.<ref name=nei-20130701>{{cite news |url=http://www.neimagazine.com/news/newshinkley-point-b-and-hunterston-b-return-to-80-load |title=Hinkley Point B and Hunterston B return to 80% load |publisher=Nuclear Engineering International |date=1 July 2013 |access-date=2 July 2013}}</ref>

In 2006 AGRs made the news when documents were obtained under the [[Freedom of Information Act 2000]] by ''[[The Guardian]]'' which claimed that [[British Energy]] were unaware of the extent of the cracking of graphite bricks in the cores of their reactors. It was also claimed that British Energy did not know why the cracking had occurred and that they were unable to monitor the cores without first shutting down the reactors. British Energy later issued a statement confirming that cracking of graphite bricks is a known symptom of extensive neutron bombardment and that they were working on a solution to the monitoring problem. Also, they stated that the reactors were examined every three years as part of "statutory outages".<ref>{{cite web|url=http://news.bbc.co.uk/1/hi/uk/5149650.stm|title=Reactor crack fears played down|website=BBC News|date=5 June 2006}}</ref>

[[File:Heysham Nuclear Power Station, Lancashire.jpg|upright=1.5|thumb|The two power stations with four AGRs at [[Heysham nuclear power station|Heysham]]]]
On 17 December 2010, EDF Energy announced a 5-year life extension for both Heysham 1 and Hartlepool to enable further generation until 2019.<ref name=ap-20101217>{{Cite news |url=https://finance.yahoo.com/news/EDF-to-extend-lifespan-of-apf-3095367761.html |title=EDF to extend lifespan of British nuclear plants |agency=Associated Press |publisher=Yahoo |date=17 December 2010 |access-date=11 April 2011 }}{{Dead link|date=August 2018 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

In February 2012 EDF announced it expected 7-year life extensions on average across all AGRs, including the recently life-extended Heysham 1 and Hartlepool. These life extensions are subject to detailed review and approval, and are not included in the table above.<ref name=nei-20120220>{{cite news|url=http://www.neimagazine.com/story.asp?storyCode=2061782 |title=EDF plans longer life extensions for UK AGRs |date=20 February 2012 |publisher=Nuclear Engineering International |access-date=16 May 2012 |url-status=dead |archive-url=https://web.archive.org/web/20131013200355/http://www.neimagazine.com/news/newsedf-plans-longer-life-extensions-for-uk-agrs |archive-date=13 October 2013 }}</ref><ref name=bbc-20140219>{{cite web|url=https://www.bbc.co.uk/news/uk-scotland-glasgow-west-26256193|title=Doosan Babcock signs EDF deal to extend nuclear plants|website=BBC News|date=19 February 2014|access-date=23 July 2021}}</ref>

On 4 December 2012 EDF announced that Hinkley Point B and Hunterston B had been given 7-year life extensions, from 2016 to 2023.<ref name=independent-20121204>{{cite news |url=https://www.independent.co.uk/news/business/news/edf-extends-life-of-two-nuclear-power-stations-8381256.html |archive-url=https://web.archive.org/web/20121208065400/http://www.independent.co.uk/news/business/news/edf-extends-life-of-two-nuclear-power-stations-8381256.html |archive-date=2012-12-08 |url-access=limited |url-status=live |title=EDF extends life of two nuclear power stations |newspaper=The Independent |date=4 December 2012 |access-date=14 August 2013}}</ref>

On 5 November 2013 EDF announced that Hartlepool had been given a 5-year life extension, from 2019 to 2024.<ref name=bbc-20131105>{{cite web|url=https://www.bbc.co.uk/news/uk-england-tees-24824816 |title=Hartlepool power station to stay open until 2024 |website=BBC News|date=5 November 2013|access-date=23 July 2021}}</ref>

In 2013 a defect was found by a regular inspection in one of the eight pod boilers of Heysham reactor A1. The reactor resumed operation at a lower output level with this pod boiler disabled, until June 2014 when more detailed inspections confirmed a crack in the boiler spine. As a precaution Heysham A2 and the sister Hartlepool station were also closed down for an eight weeks' inspection.<ref name=nei-20140811>{{cite news |url=http://www.neimagazine.com/news/newsedf-energy-shuts-heysham-a12-and-hartlepool-for-pod-boiler-inspections-4340201 |title=EDF Energy shuts Heysham A1&2 and Hartlepool for pod boiler inspections |publisher=Nuclear Engineering International |date=11 August 2014 |access-date=14 August 2014}}</ref><ref name=wnn-20140813>{{cite news |url=http://www.world-nuclear-news.org/RS-UK-regulator-backs-EDF-Energy-on-reactor-checks-1308201401.html |title=UK regulator backs EDF Energy on reactor checks |website=World Nuclear News |date=13 August 2014 |access-date=14 August 2014}}</ref>

In October 2014 a new kind of crack in the graphite moderator bricks was found at the Hunterston B reactor. This keyway root crack has been previously theorised but not observed. The existence of this type of crack does not immediately affect the safety of a reactor – however if the number of cracks exceed a threshold the reactor would be decommissioned, as the cracks cannot be repaired.<ref>{{cite web|last1=Broomby|first1=Rob|title=New cracks in Hunterston reactor|url=https://www.bbc.com/news/science-environment-29481481|date=6 October 2014|website=BBC News|access-date=23 July 2021}}</ref><ref name=rn-20141007>{{cite news |url=http://en.ria.ru/analysis/20141007/193777310/Concerns-Persist-Over-Safety-of-Cracking-Inside-Reactor-in.html |title=Concerns Persist Over Safety of Cracking Inside Reactor in Scotland: Nuclear Safery Expert |newspaper=RIA Novosti |date=7 October 2014 |access-date=10 October 2014}}</ref>

In January 2015 Dungeness B was given a ten-year life extension, with an upgrade to control room computer systems and improved flood defences, taking the accounting closure date to 2028.<ref name=wnn-20150120>{{cite news |url=http://www.world-nuclear-news.org/C-UK-nuclear-plant-gets-ten-year-extension-2001157.html |title=UK nuclear plant gets ten-year extension |website=World Nuclear News |date=20 January 2015 |access-date=21 January 2015}}</ref>

In February 2016, EDF extended the life of four of its eight nuclear power plants in the UK. Heysham 1 and Hartlepool had their life extended by five years until 2024, while Heysham 2 and Torness had their closure dates pushed back by seven years to 2030.<ref>{{cite web|first=John|last=Moylan|title=EDF to keep four UK nuclear plants open for years longer|url=https://www.bbc.co.uk/news/business-35583740|website=BBC News|date=16 February 2016|access-date=23 July 2021}}</ref>

On 7 June 2021, EDF announced that Dungeness B, which had been in an extended outage since September 2018, would move into the defuelling phase with immediate effect.<ref>{{cite web |title=EDF decides to move Dungeness B into defuelling phase |url=https://www.edfenergy.com/media-centre/news-releases/edf-decides-move-dungeness-b-defuelling-phase |website=EDF Energy |access-date=7 June 2021 |date=7 June 2021}}</ref>

On 15 December 2021 EDF announced that Heysham 2 and Torness are expected to close in March 2028.<ref>{{cite web|url=https://www.edfenergy.com/media-centre/news-releases/agr-lifetime-reviews-carried-out|title=AGR lifetime reviews carried out|website=EDF Energy|date=15 December 2021|access-date=7 January 2022}}</ref>

On 7 January 2022 Hunterston B reactor 4 was shut down for the last time, ending production after nearly 47 years. Reactor 3 had moved to the defuelling phase in November 2021.<ref>{{cite web|url=https://www.edfenergy.com/media-centre/news-releases/zero-carbon-electricity-generation-ends-hunterston-b|title=Zero-carbon electricity generation ends at Hunterston B|website=EDF Energy|date=7 January 2022|access-date=12 January 2022}}</ref>

On 1 August 2022 Hinkley Point B Reactor 3 was shut down, Reactor 4 was shut down on 6 July 2022.<ref>{{cite web|url=https://www.edfenergy.com/media-centre/news-releases/new-dawn-hinkley-point-b-ends-generation|title=A new dawn as Hinkley Point B ends generation|website=EDF Energy|date=1 August 2022|access-date=29 January 2023}}</ref>

On 3 December 2024 EDF announced an extension to the life of the UK's remaining 4 AGR nuclear power plants. Heysham 2 and Torness have been extended for an extra 2 years until 2030. Heysham 1 and Hartlepool have been given a 1 year extension until 2027.<ref>{{Cite web |date=4 December 2024 |title=EDF confirms boost to UK's clean power targets with nuclear life extensions |url=https://www.edfenergy.com/media-centre/edf-confirms-boost-uks-clean-power-targets-nuclear-life-extensions |access-date=6 December 2024 |website=EDF Energy Press Releases}}</ref>

In January 2025, EDF announced that their "ambition is to generate beyond these dates, subject to plant inspections and regulatory oversight", although they expect "that by the mid-2030s all seven of the AGR power stations will be owned by the UK Government" (for decommissioning).<ref>{{Cite web |date=January 2025 |title=UK Nuclear Fleet Stakeholder Update |url=https://www.edfenergy.com/sites/default/files/2025-01/FM11351-UK-Nuclear-Fleet-Strategy-Update-2025-FINAL.pdf}}</ref>