Sizewell B granted 20-year lifetime extension

On July 8, 2026, the government agreed a deal with EDF and Centrica to grant Sizewell B a 20-year lifetime extension. Officials said the extension will help protect customers from volatility in fossil fuel markets and will retain 900 jobs. Reaction pending.

Deal with EDF and Centrica

Officials described the agreement as a commercial arrangement to keep the reactor online beyond its previous planned closure date. The government framed the move as a supply-side measure to stabilise baseload generation and reduce exposure to gas-market swings; officials said it is intended to offer long-term price resilience for consumers.

Market participants and generators will watch for contract mechanics and cost allocation. The extension locks an existing low-carbon asset into the UK supply mix for two extra decades, which could reduce near-term demand for incremental gas-fired capacity while leaving long-term decarbonisation and new-build needs unchanged.

Policy and regulatory checks remain. Officials said further deal documentation will be published, with full terms expected by July 15, 2026, allowing industry and Parliament to assess subsidy exposure and operational responsibilities.

The immediate market impact is likely limited, but the extension changes capacity planning for utilities and investors, and will be weighed alongside ongoing discussions about UK energy security and capacity adequacy.