The National Audit Office (NAO) has issued a stark warning regarding the government's £38 billion Sizewell C nuclear plant in Suffolk, stating that the potential benefits for UK households may not materialize until at least 2064. The spending watchdog highlighted that the project's costs are subject to significant uncertainty, with risks that are immediate, substantial, and borne by the public.
Risks Outweigh Benefits
According to the NAO, while the potential benefits of the Sizewell C plant are considerable, they remain highly uncertain. The government claims the reactor, expected to generate enough low-carbon electricity to power 6 million homes when it begins operations in the late 2030s, could save £2 billion annually from the electricity system compared to other low-carbon technologies. However, for households, the overall savings could be outstripped by the cost of supporting its construction until almost halfway through its 60-year operational life. The project could take even longer to break even if cost overruns or delays occur.
Expert Commentary
Sir Geoffrey Clifton-Brown, chair of the public accounts committee, emphasized the exceptional scale and complexity of Sizewell C, noting that comparable nuclear projects in the UK and overseas have been vulnerable to delays and cost overruns. He stated, "Sizewell C is a project of exceptional scale, complexity and significance for taxpayers."
Project Stakeholders
Sizewell C is being developed by French state nuclear company EDF as a successor to the Hinkley Point C reactor in Somerset. EDF has invested £1.1 billion for a 12.5% stake, while the UK government is the majority stakeholder with £14.2 billion. British Gas's parent company, Centrica, owns 15%, and the Canadian pension fund La Caisse and investment fund Amber Infrastructure hold 20% and 7.6%, respectively.
CEO's Defense
Nigel Cann, chief executive of Sizewell C, defended the project, calling the cost on household bills an "investment in lower long-term electricity costs" that will deliver value to consumers and the country for the rest of this century. He added that the project is already creating thousands of jobs and boosting businesses, with nearly £5 billion spent on UK suppliers, meeting the 70% domestic sourcing target.
Funding Model Concerns
Households began paying for Sizewell C via energy bills at the start of 2024 under a regulated asset base (RAB) model, a shift from the Hinkley Point deal. Critics, including the campaign group Stop Sizewell C, warn that construction delays could leave bill payers supporting the plant without receiving power for longer than expected, while the government assumes financial risk. Stop Sizewell C stated that the risks "could easily turn Sizewell C into a financial disaster" and that investors are "the only ones who can't lose."
Government Response
A government spokesperson argued that investing in large-scale nuclear power is the only way to escape volatile global gas markets. The NAO has urged the government to mitigate risks through close monitoring, greater transparency to parliament, and securing value for money from public and private investment.
