In advance of the Spending Review, the government has committed £14.2 billion to the construction of the new Sizewell C nuclear facility on the Suffolk coast.
According to the Treasury, Sizewell C nuclear reactor will generate enough energy to power six million homes while also creating 10,000 direct jobs and many more in enterprises that service the plant.
Chancellor Rachel Reeves said the “landmark decision” would “kickstart” economic growth, while Energy Secretary Ed Miliband said the investment was necessary to usher in a “golden age of clean energy”.
However, Alison Downes, director of pressure group Stop Sizewell C, said ministers had not “come clean” about Sizewell C’s cost, because “negotiations with private investors are incomplete”.
After construction begins, Sizewell C will take at least a decade to complete.
Reeves said it would be the “biggest nuclear building programme in a generation”.
Ms Downes added she believed the investment could be spent on other priorities and feared the project would “add to consumer bills”.
Miliband said the project was part of the government making “long-term decisions for the future of the country” and it would tackle the climate crisis by “getting [the UK] off insecure, expensive and volatile fossil fuels”.
He said: “I remember as a young cabinet minister identifying in 2009 Sizewell as a potential new site for nuclear and I didn’t expect it would be me back doing it and making it happen.”
He said the project would replicate the Hinkley Point C nuclear power station in Somerset.
“Sizewell will reap the benefits of replicating what happened at Hinkley. We are confident it can be built cheaper and faster.”
The government claims that nuclear power produces large amounts of low-carbon, non-intermittent energy, which is a critical component of the government’s ambitions to nearly eradicate fossil fuels from the UK’s energy grid by 2030.
Hinkley Point C in Somerset, the other major facility to which Sizewell C nuclear reactor is a replica, will begin operations in the early 2030s, more than a decade later and costing billions more than initially envisaged.
The Sizewell C nuclear reactor investment is the latest in a series of announcements leading up to the government’s Spending Review, which will be released on Wednesday.
During the review, the chancellor will outline the day-to-day expenditure and investment goals for each government department.
A number of initiatives have already been published, including a reversal on winter fuel payments, a pledge to raise defence spending, and investments in science and technology.
In the 1990s, nuclear power produced approximately 25% of the UK’s electricity. However, that proportion has dropped to approximately 15%, with all but one of the UK’s existing nuclear fleet set to be dismantled by 2030.
The previous Conservative administration approved the construction of Sizewell C in 2022.
Sizewell C has since received government approval for further finance, and a formal procedure to collect private investment will begin in September 2023.
Ministers and EDF, the French state-owned energy firm that owns 15% of Sizewell C, have previously stated that there are numerous potential investors and that a deal is close to being reached.
The final decision on the plant’s funding strategy is due later this summer.
The Sizewell C project has met resistance both locally and nationally from individuals who believe it will be a costly mistake.
“There still appears to be no final investment decision for Sizewell C but £14.2bn in taxpayers’ funding, a decision we condemn and firmly believe the government will come to regret,” she said.
“Starmer and Reeves have just signed up to HS2 mark 2,” she added, referring to the railway project mired by years of budget disputes and delays.
On 7 June 2025, some 300 protestors gathered on Sizewell Beach to oppose the project, with many concerned about how the plant will affect the environment.
Once operational, Sizewell C is planned to employ 900 workers.
In addition to Sizewell C, the government announced a £2.5 billion investment over five years in fusion energy research and development, as well as investments in the defence nuclear business.
This included the expansion of HMNB Clyde and funding in Sheffield Forgemasters.