Contract signed for IMSR fuel pilot plant

04 August 2023

Terrestrial Energy has signed a manufacturing and supply contract with Westinghouse subsidiary Springfields Fuels Limited to deliver a pilot Integral Molten Salt Reactor (IMSR) fuel plant in the UK, paving the way to provide the fuel to support future fleet deployment of IMSRs. The project is receiving support from the UK government's Nuclear Fuel Fund.

Representatives from Terrestrial Energy and Westinghouse Springfields Fuels at signing of contract (Image: Terrestrial Energy)

The extensive existing infrastructure already available at Springfields' reactor fuel manufacturing site in Preston, in the north-west of England, will be able to support the fuel supply for IMSR development, and is  scalable to be able to support a fleet of IMSR plants operating in the 2030s, Terrestrial said. 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 operating in the 2030s.

The new contract is the result of a partnership set up in 2021 by Westinghouse, the UK's National Nuclear Laboratory and Terrestrial Energy to advance the industrial scale-up and commercial supply of enriched uranium fuel for use in the IMSR. The UK government has committed GBP2.9 million (USD3.8 million) to establish the pilot plant under its Nuclear Fuel Fund programme, Terrestrial said.

Terrestrial's IMSR is a 4th generation reactor that uses molten salt as both fuel and coolant, with integrated components, which can supply heat directly to industrial facilities or use it to generate electrical power. It does this using conventional nuclear reactor fuel - standard assay low-enriched uranium (LEU).

The use of LEU fuel, which is available and transportable today for civilian reactor use and has international regulatory acceptance, supports an early deployment path for IMSR plants, according to Terrestrial. This is not the case for the high-assay low-enriched uranium (HALEU) fuel which will be used by many of the advanced reactor designs currently being developed: supply chain constraints have already prompted a two-year delay to TerraPower's planned first-of-a-kind Natrium demonstration reactor in Wyoming, USA, while Danish developer of floating compact molten salt reactors Seaborg recently announced a switch to LEU instead of HALEU fuel for its first power barges because of risks to the project timeline.

IMSR fuel can also be transported using reactor fuel packaging already in use today, which has commercial implications for early deployment of IMSR plants, according to Terrestrial Energy: there are no large-capacity, commercially viable transport containers licensed for HALEU.

"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," Terrestrial Energy CEO Simon Irish said. "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."

Last month, Westinghouse was awarded three grants totalling GBP10.5 million (USD13.6 million) from the UK's Nuclear Fuel Fund to upgrade and expand the Springfields fuel fabrication facility to develop more variants of light-water reactor fuels for large and small reactors, as well as to support the potential production of HALEU advanced nuclear fuels for the UK's new advanced reactors.

Researched and written by World Nuclear News