Sizewell C Nuclear Power Station

Sizewell C is being built as a near-copy of Hinkley Point C, and that’s the point.

The station will carry two EPR reactors at 1.6 GW each, 3.2 GW total, on the Suffolk coast near Leiston. Construction formally started in January 2024. At the two-year milestone the project reported nearly 2,000 workers on site, more than 100 apprentices, and around £3 billion of contracts placed with over 400 British suppliers, close to £1 billion of that in the East of England.

Project Scope

Final investment decision came in July 2025 at an estimated £38 billion in 2024 prices, roughly $51 billion. Ownership sits with Sizewell C Ltd: the UK Government holds 44.9 percent alongside EDF, Centrica, La Caisse, and Amber Infrastructure. The financing runs on the Nuclear Regulated Asset Base model, which recovers construction cost from electricity consumers during the build rather than after it.

The Civil Works Alliance signed its Programme Alliance Agreement on 30 June 2025: Balfour Beatty, Laing O’Rourke, and Bouygues Travaux Publics, all three of them also on Hinkley Point C. Amentum is the sole programme and project management delivery partner. Jacobs was appointed on 20 January 2026 for programme integration, delivery oversight, and technical support through 2030. AtkinsRéalis signed a five-year framework on 6 July 2026 as design partner for permanent civil works. Wilson James runs logistics. Three ground engineering specialists were brought together for the piling works in July 2026.

Peak workforce is projected at about 10,000, with roughly 1,500 apprenticeships and a target of 70 percent UK-based supply chain spend. Construction is expected to complete by summer 2039, with the units designed for at least 60 years of operation.

Why It Matters

Design replication is the entire delivery thesis. Hinkley Point C absorbed the first-of-a-kind cost and schedule pain of building an EPR in the UK regulatory environment; Sizewell C is meant to harvest it. Same reactor, largely the same civils contractors, much of the same supply chain. If nuclear new-build in Britain is ever going to get cheaper, this is where it has to show up.

RAB financing changes the contracting environment in ways that reach down to package level. Economic regulation brings allowable capital spend limits, formal cost reporting, and defined intervention thresholds if overruns emerge. Contractors face tighter change control and independent verification than they would under a conventional CfD-backed build. That’s a discipline the UK nuclear supply chain hasn’t worked under before.

Project Team & Details