The UK government is moving ahead with plans to secure a vital part of the nation's energy infrastructure, with the Department for Energy Security and Net Zero (DESNZ) proposing a significant subsidy to EDF Energy Nuclear Generation Ltd. The subsidy, a 'Subsidy of Particular Interest', is designed to enable the long-term operation of the Sizewell B nuclear power plant in Suffolk, extending its life by an additional 20 years beyond its current scheduled shutdown in 2035.
This proposal has now been formally referred to the Subsidy Advice Unit (SAU), which today, 22 July 2026, confirmed it has accepted the request for a report. The SAU will assess whether DESNZ's proposed subsidy complies with the UK's subsidy control requirements. Their evaluation is expected to be completed within 30 working days, after which their findings will be provided to DESNZ.
Sizewell B, which began generating electricity in 1995, has been a significant contributor to the UK's low-carbon energy mix, producing over 260 terawatt-hours to date. Without this proposed intervention, the plant is currently slated to cease operations in 2035. However, technical assessments indicate it can continue generating for at least two additional decades, prompting DESNZ's intervention.
The proposed support will come in the form of a bespoke Contract for Difference (CfD) arrangement. Under this scheme, EDF Energy Nuclear Generation Limited (ENGL), the plant's owner and operator, would receive revenue support. This support would be linked to the difference between an agreed 'strike price' and the prevailing wholesale electricity price, providing revenue certainty for the extended operational period. This aims to enable ENGL to undertake necessary investments and activities to ensure the plant's continued safe and reliable operation.
DESNZ asserts that extending the operational life of existing nuclear power stations, such as Sizewell B, represents the most cost-effective method for increasing nuclear generation capacity. Government analysis suggests that prolonging Sizewell B's life will reduce overall system costs compared to alternative low-carbon energy scenarios without the project. Furthermore, the subsidy is intended to bolster the government's objectives of enhancing security of supply, as nuclear power provides stable, low-carbon electricity irrespective of weather conditions. The extension is also anticipated to sustain a highly skilled workforce and support the wider UK nuclear supply chain.
Members of the public and organisations wishing to comment on the SAU's evaluation of the subsidy's compliance can submit their feedback via email to sau-sizewellb2026@cma.gov.uk, copying lifetimeextensions@energysecurity.gov.uk. Submissions must include consent for sharing with DESNZ and should indicate any commercially confidential information.