Terrestrial Energy signed a manufacturing and supply contract with Springfields Fuels Limited, a subsidiary of Westinghouse, for the design and construction of an Integral Molten Salt Reactor (IMSR) fuel pilot plant. Springfields’ reactor fuel manufacturing site in Preston, United Kingdom has extensive existing infrastructure that is available today to support the fuel supply for IMSR development, and scalable to support a fleet of IMSR plants operating in the 2030s.

The new contract will deliver a pilot plant in advance of a scaled-up facility for commercial reactor fuel supply to a fleet of IMSR plants. The UK Government has committed GBP 2.9 million (USD $3.8 million) to establish the pilot plant under its Nuclear Fuel Fund program, part of the UK’s energy security strategy. The contract is a result of partnership between Terrestrial Energy, Westinghouse Springfields Fuels and UK National Nuclear Laboratories, and follows the scoping and planning agreement signed in July 2021.

The IMSR uses next-generation fission technology – Generation IV technology – to deliver transformative improvements in the commercial performance and versatility of nuclear energy. It does this using conventional nuclear reactor fuel – Standard Assay Low Enriched Uranium (LEU). This is the only fuel available and transportable today for civilian reactor use and has international regulatory acceptance. Its use supports an early deployment path for IMSR plants.

“We are excited to work with Terrestrial Energy to develop a pilot plant creating next-generation nuclear fuel at Springfields to power molten salt reactors,” said Tarik Choho, President of Westinghouse Nuclear Fuel. “This is yet another important vote of confidence in the UK nuclear industry broadly, and specifically for Westinghouse products, services, and people that support energy security and net-zero goals.”

“Our commercial strategy for IMSR is to use existing nuclear industrial infrastructure, materials, skills and capabilities to the greatest extent in the operation of the IMSR plant,” said Simon Irish, CEO of Terrestrial Energy. “This strategy, focused on capital efficiency, is clearly expressed with the use of Standard Assay LEU fuel, and repurposing of the extensive fuel production capabilities at the Springfields site. We are delighted to be moving forward with our Springfields fuel manufacturing and supply plans in partnership with Westinghouse and with funding support from the UK government.”

In April 2023, the Canadian Nuclear Safety Commission (CNSC) concluded, following a systematic and multi-year review against Canadian regulatory requirements, that there were no fundamental barriers to licensing the IMSR plant for Canadian commercial use. This was the first regulatory review of a commercial nuclear plant using molten salt reactor technology and the first advanced, high-temperature fission technology to complete a review of this type.

Terrestrial Energy completed an independent third-party regulatory evaluation of packaging and cross-border transportation of Standard Assay LEU fuel in November 2022. This work demonstrated that existing reactor fuel packaging used to service the nuclear industry is suitable for the transportation and supply of IMSR fuel. This outcome avoids the costly and lengthy process of designing, licensing and manufacturing new nuclear fuel packaging, and has important commercial implications for early deployment of IMSR plants in key markets. It reflects the advantage of the IMSR fuel choice, as there are no large-capacity, commercially viable transport containers licensed for High Assay LEU (HALEU).

Springfields Fuels Limited, a subsidiary of Westinghouse, is a global leader in the supply of uranium fuel for today’s commercial nuclear power reactors. This supply includes Standard Assay LEU, which over many decades has become the commercial fuel standard. Standard Assay LEU is enriched to up to 5 percent uranium-235, and is available from plants in United Kingdom, France, and other countries. Terrestrial Energy’s use of Standard Assay LEU fuel in IMSR operation, the only Generation IV reactor design in North America to do so today, is necessary for an early and clear path to fleet deployment in the 2030s.

Terrestrial Energy is engaged with a diverse range of industrial companies in North America, Europe and Asia, operating large energy and emissions-intensive plants in multiple jurisdictions worldwide, seeking to offset emissions and source reliable, zero-carbon energy supply. The unique capabilities of the IMSR plant to provide this clean energy to industry can help achieve these goals.