The four shortlisted companies in the small modular reactor (SMR) selection process are GE Hitachi, Holtec, Rolls-Royce SMR and Westinghouse. Negotiations began on Monday ahead of the submission of final tenders, with a final decision now expected to be taken in "spring" next year (March to May).

Great British Nuclear (GBN) Chairman Simon Bowen said: "This is a significant moment for the SMR programme. Our technical experts have assessed each design in detail and are very confident these SMRs could play a key role in the UK’s future energy mix. The negotiation phase will enable us to select the absolute best technologies on the best terms for the UK."

In the statement announcing the start of the negotiations which will take place with each of the bidders, GBN said: "To reach this stage, each of the four designs was subject to a robust analysis. GBN has evaluated each technology, including aspects such as safety, deliverability, and their ability to support development of a fleet of SMRs. GBN considers the designs, each of which is proceeding through the UK’s regulatory process, are viable options for development. Subject to negotiations, GBN consider any one of these designs would be fit to use in the UK nuclear programme."

The background
 

GE Hitachi is putting forward its BWRX-300, a boiling water reactor, Holtec's SMR-300 is a 300 MWe pressurised water reactor, the Rolls-Royce SMR is a 470 MWe pressurised water reactor and Westinghouse's AP300 is a 300 MWe/900MWth pressurised water reactor. They all stress that their designs are based on existing technologies and will be able to be constructed at speed and benefit from modular production techniques.

In an interview earlier this year for the World Nuclear News podcast, GBN Chairman Simon Bowen said the intention was to place contracts with one, two or three technology providers - this would be for co-funding the technology all the way through to completion of the design, regulatory, environmental and site-specific permissions process, and the potential to place a contract for the supply of equipment. Each selected technology would have an allocated site with the potential to host multiple SMRs.

The aim is then for a final investment decision to be taken in 2029.

There has since been a change of government in the UK, but it has pledged to continue with the process, although it announced in the Budget that the timeline for the selection decision has slipped from the end of this year to spring 2025. The timeline for the final investment decision remains unchanged.