Rolls-Royce SMR and Great British Energy - Nuclear have signed a contract that enables work to start immediately on the delivery of three Rolls-Royce small modular reactors at Wylfa, on the island of Anglesey, North Wales. 

The National Wealth Fund has pledged up to GBP599 million (USD805 million) to Rolls-Royce SMR to support the development of its reactor technology. The company has been chosen by the UK government as the preferred provider for the nation’s first small modular reactor (SMR) project. In addition, GBP2.6 billion was earmarked in the 2025 Spending Review to facilitate this contract and support the broader rollout of the SMR programme.

The Rolls-Royce SMR design delivers around 470 MWe and is based on a compact pressurised water reactor. It is intended to supply reliable baseload electricity for a lifespan of at least 60 years. About 90% of the reactor—roughly 16 metres by 4 metres in size—will be manufactured in controlled factory environments, meaning on-site work will largely involve assembling pre-fabricated and pre-tested modules. This approach helps lower project risks and can significantly accelerate construction timelines. In October 2024, Rolls-Royce SMR was chosen by ČEZ to deliver up to 3 GW of electricity capacity in the Czech Republic, with ČEZ also acquiring a 20% stake in the company. Separately, the UK government confirmed that Wylfa will host three Rolls-Royce small modular reactors. The site—currently undergoing decommissioning of a former Magnox nuclear plant—has the potential to accommodate as many as eight SMRs in the future.

On 1 April, Great British Energy – Nuclear announced it had awarded a GBP300 million (US$403.4 million) contract to a joint venture between Amentum and Cavendish Nuclear to act as the Owner’s Engineer for the deployment of Rolls-Royce SMR reactors at Wylfa. Operating under the name Litmus Nuclear, the partnership will provide independent oversight and specialist technical support across key areas such as design, safety, engineering, construction, and commissioning. The contract could run for up to 14 years and is intended to ensure the programme complies with all regulatory standards while supporting progress toward a final investment decision for the UK’s first SMRs, which is currently anticipated in 2029.