Terrestrial Energy, Westinghouse and UK NNL collaborate on IMSR Fuel

19 August 2021


US-based Westinghouse, the UK National Nuclear Laboratory (NNL), and US-based Terrestrial Energy on 17 August signed an agreement for nuclear fuel development and supply to advance the industrial scale up and commercial supply of enriched uranium fuel for use in Terrestrial Energy’s Integral Molten Salt Reactor (IMSR). The Terrestrial Energy IMSR, a Generation IV advanced nuclear power plant is under development in Oakville.

Westinghouse’s UK facility, Springfields, is a global supplier of uranium fuel for commercial nuclear power reactors. The NNL provides critical technical support services to Westinghouse from its research facility co-located on the Springfields site.

IMSR fuel utilises Standard Assay Low Enriched Uranium (LEU), which over many decades has become the commercial fuel standard. Standard Assay LEU is enriched to up to 5% uranium-235, at plants in Germany, the Netherlands, the UK, and the USA. Terrestrial Energy’s use of Standard Assay LEU fuel in IMSR operation, the only Generation IV reactor design to do so today, supports early deployment.

NNL CEO Paul Howarth said: “The development of the IMSR power plant provides a fundamental platform that showcases the vast potential of the Springfields site. The agreement also harnesses NNL’s expertise in collaboration with Westinghouse global fuels experience and capabilities, which is vital to expand the supply capability for advanced reactor fuels.” He added: “As the expansion plan continues, we are delighted that the advanced reactor sector recognises our capabilities and Terrestrial Energy has selected Westinghouse and NNL to develop the commercial fuel supply. We look forward to implementing the processes and facilities, creating jobs which will be pivotal in supporting the first operating IMSR nuclear power plant.” 

Sophie Lemaire, Regional Vice President, Westinghouse, said: “We have the knowledge, technology and capability to develop new fuel manufacturing routes for advanced nuclear technologies. These technologies will support skilled manufacturing jobs at our Springfields site in Lancashire, a strategic national asset for the United Kingdom, employing around 800 high value jobs in the region.”

Terrestrial Energy CEO Simon Irish noted: “We have designed IMSR to use Standard Assay LEU fuel as it is today’s nuclear fuel standard and is readily available for civilian use. This is a major advantage for early deployment. Terrestrial Energy is working on a multiple sourcing strategy for IMSR fuel supply, and we recognise the world-class fuel expertise and production capabilities at the National Nuclear Laboratory and Westinghouse Springfields. Our agreement is an important step to demonstrate reliable, secure and long-term commercial supply of reactor fuel to utilities operating IMSR power plants.”

The agreement between Terrestrial Energy, Westinghouse and the National Nuclear Laboratory defines the process for delivering IMSR fuel for commercial use, concurrent with schedules for commercial operation of IMSR power plants by electric utility customers.

Terrestrial Energy said it is engaged with regulators and industrial partners to complete IMSR engineering and to commission first IMSR power plants in the late 2020s. 


Photo: Rendering of the IMSR® Core-unit (Credit: Terrestrial Energy)



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