The anticipated cost to build the Sizewell C nuclear power station in Suffolk may soar to nearly £40 billion, according to insiders involved in discussions regarding this major energy initiative. This figure nearly doubles the £20 billion forecast from EDF and the UK government in 2020, a surge attributed to rising construction expenses and complications faced at the nearby Hinkley Point C site.
This increased estimate raises significant concerns about the government’s nuclear energy strategy, especially given the current strain on public finances and the ongoing cost-of-living crisis. EDF claims that once operational, Sizewell C could provide low-carbon electricity to about 6 million homes for a span of 60 years.
The Treasury is set to determine whether the project will proceed during its upcoming multi-year spending review. Initially backed by the UK government and EDF, efforts are underway to secure additional investments, a process that is taking longer than initially expected.
Recent statements from the Department for Energy Security and Net Zero (Desnz) indicate they cannot disclose the latest cost estimate as it remains “commercially sensitive.” However, a senior government official and two industry insiders have suggested that a more accurate estimate for building Sizewell C could be around £40 billion when adjusted for 2025 prices.
The government has already committed £3.7 billion in public funds to the project. While ministers aimed to finalize an investment decision by late 2024, that timeline has been pushed back to spring 2025, sparking discussions that it could extend even further.
Potential investors range from Centrica and Schroders Greencoat to the Emirates Nuclear Energy Corporation and Amber Infrastructure Group. Reports indicate that Sizewell C is making steady progress in securing private investments.
Campaign groups, such as Stop Sizewell C, are urging transparency regarding the project’s true costs, which will ultimately be borne by households through energy bills. Alison Downes, the group’s executive director, has criticized the lack of clarity, stating, “This secrecy around Sizewell C is inexcusable.”
Dale Vince, an influential donor to the Labour party and founder of Ecotricity, has raised alarms about the financial implications for consumers, expressing concerns that the project might lead to higher energy bills long before it produces any power. He stated, “Nuclear is too expensive, too slow—and very costly to manage at the end of its lifecycle.”
Currently, nuclear energy accounts for about 14 percent of the UK’s electricity supply, and many experts believe it will play a crucial role in reducing carbon emissions to net zero by 2050. Nevertheless, most of the UK’s aging nuclear plants are set to close by March 2030 unless life-extension plans are approved.
At present, only one new nuclear facility is under construction in the UK—Hinkley Point C—which faces delays and budget increases. Initial projections from 2016 set its launch for late 2025 with a projected cost of £18 billion, but it is now expected to generate power in 2029 at the earliest, with costs potentially climbing to £46 billion.
Sizewell C is designed using the same European Pressurised Water technology as Hinkley Point C, but EDF insists it should be more cost-effective due to lessons learned and better-developed supply chains. Additionally, it employs a different financial structure, the regulated asset base model, which allows developers to receive payments from consumers during construction, rather than waiting until the plant is completed.
Despite the optimism surrounding this project, there remains skepticism about how much lower the final price tag for Sizewell C will be compared to Hinkley Point C. Challenges have also arisen with the recent resignation of Rob Holden as chair of Sizewell C Limited due to health issues.
A spokesperson from Desnz has contested the £40 billion figure, saying, “The project is expected to lower electricity system costs, enhance our capacity for secure domestic energy, and generate significant nationwide investment.”