UK nuclear projects delayed by five years due to legal challenges, report finds

Delays to Britain’s two planned nuclear power stations have stretched to about five years because of spurious legal challenges, according to a Britain Remade report.

A total of 1,754 days have been added to the construction timelines of Hinkley Point C in Somerset and Sizewell C in Suffolk, with seven separate legal challenges against nuclear projects in the last twelve years. Six of the challenges have been planning-related, the report notes, and the delays have raised questions about project viability, financing costs, and the impact on electricity supply in the 2030s.

The Greenpeace-led challenge against Hinkley Point C accounted for a 150-day delay before it was withdrawn, while the longest disruption reached 625 days and ended only after the Supreme Court refused permission to appeal a High Court ruling in the project’s favor in Somerset. Britain Remade’s analysis emphasizes that the financial impact of delays grows when financing costs are high, which is the case for large, capital-intensive nuclear projects.

Sizewell C, the Suffolk site, has endured 827 days of legal challenges since August 2022, with one additional coastal flood defence case still pending. Taken together, the two projects have seen cost increases that critics say fuel higher bills for taxpayers and consumers. Hinkley Point C’s projected price tag remains around £46 billion—roughly double the cost of comparable plants built in France and Finland—while Sizewell C is now estimated at about £38 billion. The projects are also expected to deliver sizeable portions of the UK’s future electricity mix: Hinkley Point C is slated to open by 2031 and generate around 7% of the country’s electricity in the 2030s, while Sizewell C is planned to power about six million homes for at least 60 years once operational in the mid-to-late 2030s.

Britain Remade argues that planning-law structures in the UK, including requirements around coastal defences and environmental protections, contribute to the delays. Among the cited items is the acoustic deterrent that critics have labeled the “fish disco” near Hinkley Point C’s water intake, a feature intended to protect aquatic life but one of several planning hurdles cited in the report.

The report notes that seven legal challenges against nuclear projects have arisen in the last twelve years, with six focused on planning issues. In total, Hinkley Point C has faced 866 days of delay, while Sizewell C has endured 827 days since August 2022. One add-on related to coastal flood defences remains unresolved as of the report’s publication.

The government has argued that reforms are underway to streamline licensing and approvals. In the case of Sizewell C, the government will hold a 44.9% equity stake, and the project is part of a broader push to revive nuclear construction in Britain. The government also highlighted a deal for Sizewell C, the selection of Rolls-Royce SMR as the preferred bidder to advance one of Europe’s first small modular reactor programmes, and a collaboration with the United States to reduce licensing time from four years to two.

The last new nuclear plant completed in Britain was Sizewell B in 1987, underscoring the scale of the current build program and the potential implications of delays for energy security and climate goals. Supporters say the projects will help diversify the UK’s energy mix and reduce reliance on fossil fuels, while opponents caution about higher costs and the risks inherent in large-scale nuclear capital.

If the current planning and licensing pathway remains slow, analysts warn that the expected benefits of the nuclear program could be offset by continued cost escalation and extended project timelines. The debate over how best to reach net-zero targets includes questions about balancing rapid decarbonization with the financial and logistical realities of building new nuclear capacity in a high-cost environment.