Key questions answered on Sizewell C after Reeves confirms nuclear investment

Independent

10-06-2025

Chancellor Rachel Reeves has signed off on a £16 billion investment in nuclear power, including funding to build the Sizewell C nuclear power station.
It comes ahead of the spending review on Wednesday, where Ms Reeves will outline departmental budgets for the next three years.
Here we answer key questions about Sizewell C and the Government's wider nuclear power plans.
– What is the Sizewell C nuclear plant?
Sizewell C was first proposed 15 years ago on a site by the hamlet Sizewell, which sits on the Suffolk coast between Aldeburgh and Southwold.
The area is already home to two separate power stations, the decommissioned Sizewell A nuclear plant and pressurised water reactor Sizewell B.
Nuclear power plants use a process called nuclear fission, where atoms split, releasing heat which is then used to generate electricity.
– How much funding has the Government announced?
The Chancellor said £14.2 billion will be invested to build the Sizewell C plant, marking the end of a long journey to secure funding for the project since it was first earmarked in 2010.
At the peak of construction, Sizewell C is expected to provide 10,000 jobs.
The company behind the project has already signed £330 million worth of contracts with local businesses.
Elsewhere, the Government confirmed one of Europe's first small modular reactor (SMR) programmes, backed by £2.5 billion in taxpayers' money over five years.
Ministers announced Rolls-Royce as the winners of a long-running competition on Tuesday for the bid to build the SMR programme.
– How could Sizewell C contribute to the UK's future energy system?
Sizewell C will power the equivalent of six million homes and is planned to be operation in the 2030s, the Government said.
It is also understood that the plant will generate electricity for 60 years.
The Treasury said that, combined with the ambition to build SMRs, it would deliver more new nuclear energy to the grid than over the previous half century by the 2030s.
It comes as nuclear plants are seen as increasingly important electricity sources as the Government tries to decarbonise Britain's grid by 2030, replacing fossil fuels with green power.
The last time Britain completed one was in 1987, which was the Sizewell B plant.
Hinkley Point C, in Somerset, is under construction and is expected to produce enough power for about six million homes when it opens, but that may not be until 2031.
Sizewell C is part of the Government's wider ambitions to support clean power, such as wind and solar, and decarbonise the country's power grid to tackle the climate crisis and ensure future energy security.
– What are small modular reactors?
SMRs are a nuclear fission reactor that are a fraction of the size of a traditional nuclear plant.
This means they can be built on smaller sites across the country, closer to where the electricity is needed.
Still an emerging technology, only China and Russia have successfully built operational SMRs.
The Government says the newly-announced UK project could support up to 3,000 new skilled jobs and power the equivalent of around three million homes, with a first site expected to be allocated later this year by state-owned Great British Energy – Nuclear.
The hope is eventually attract private investment, especially from tech companies, which might build SMRs to power data centres. – Who has welcomed the Government funding?
Trade unions welcomed the move, which the Treasury said would go towards creating 10,000 jobs, including 1,500 apprenticeships.
The GMB union said giving Sizewell C the go-ahead was 'momentous'.
Regional secretary Warren Kenny said: 'Nuclear power is essential for clean, affordable, and reliable energy – without new nuclear, there can be no net zero.
'Sizewell C will provide thousands of good, skilled, unionised jobs and we look forward to working closely with the Government and Sizewell C to help secure a greener future for this country's energy sector.'
Mike Clancy, general secretary of Prospect, said: 'Delivering this funding for Sizewell C is a vital step forward, this project is critical to securing the future of the nuclear industry in the UK.
'New nuclear is essential to achieving net zero, providing a baseload of clean and secure energy, as well as supporting good, unionised jobs.
'Further investment in SMRs and fusion research shows we are finally serious about developing a 21st-century nuclear industry.
'All funding must be backed up by a whole-industry plan to ensure we have the workforce and skills we need for these plans to succeed.'
– Who has criticised the plans?
Various campaigners oppose the plant and have criticised the decision to commit the funding, saying it is still not clear what the total cost will be.
Alison Downes of Stop Sizewell C said ministers had not 'come clean' about the full cost of the project, which the group has previously estimated could be some £40 billion.
'There still appears to be no final investment decision for Sizewell C, but £14.2 billion in taxpayers' funding, a decision we condemn and firmly believe the Government will come to regret.
'Where is the benefit for voters in ploughing more money into Sizewell C that could be spent on other priorities, and when the project will add to consumer bills and is guaranteed to be late and overspent just like Hinkley C?
'Ministers have still not come clean about Sizewell C's cost and, given negotiations with private investors are incomplete, they have signed away all leverage and will be forced to offer generous deals that undermine value for money. Starmer and Reeves have just signed up to HS2 mark 2.'
Environmental campaigners have also warned of the impact the plant could have on local wildlife, given Sizewell is surrounded by protected areas.
The whole coast is an area of outstanding natural beauty (AONB), the shingle beach is a site of special scientific interest (SSSI) while the nearby Sizewell Marshes and Leiston Sandlings are special protected areas (SPAs) for birds.
Many argue that ministers should focus on investing in renewable energy, such as wind farms, instead.