Canadian nuclear energy company Terrestrial Energy has made a breakthrough in the commercial development of its Integral Molten Salt Reactor (IMSR) power plant, after the Canadian Nuclear Safety Commission (CNSC) completed Phase 2 of the pre-licensing Vendor Design Review (VDR). The development marks the first advanced, high-temperature fission technology to complete a review of this type, bringing the small modular reactor (SMR) tantalisingly close to market.

The IMSR plant is a modular nuclear plant designed to be sited close to its industrial end user. Unlike water-cooled reactors, the IMSR can supply heat in excess of 585°C (1,085°F), increasing the efficiency of electric power generation by nearly 50% and expanding the use of nuclear energy to zero-carbon industrial cogeneration (heat and power) for the first time.

The reactor is designed to use standard assay low enriched uranium (LEU) civilian nuclear fuel, enriched to less than 5%, thereby avoiding the need for high assay LEU fuel. This ensures a stable supply of fuel essential for a fleet of IMSR plants operating in the 2030s and increases the IMSR’s international regulatory acceptance.

Following an extensive multi-year review, CNSC staff concluded that there were no fundamental barriers to licensing the IMSR plant.

“The VDR is a comprehensive pre-licensing regulatory review, and its completion is a breakthrough for Terrestrial Energy,” said Simon Irish, CEO of Terrestrial Energy, in a press statement. “Its scope and conclusion provide commercial confidence to proceed to licensing and construction of IMSR plants. It is the first technology review completed by a major regulator of a nuclear plant design that uses a Generation IV reactor technology to supply heat at high temperature, and the first time for molten salt reactor technology.

“This review is a major step to bring molten salt technology to commercial markets and IMSR plants to large industrial companies seeking practicable high-impact solutions to decarbonise industrial production.”