Molten Salt reactor passes crucial test
Oakville, Ontario-based Terrestrial Energy, a developer and vendor of advanced nuclear reactors, announced November 8 that it has successfully completed the first phase of the Canadian Nuclear Safety Commission’s (CNSC) pre-licensing vendor design review for its Integral Molten Salt Reactor (IMSR) nuclear power plant design.
Terrestrial Energy Chief Executive Officer Simon Irish said: “Completing phase 1 of the vendor design review – the first advanced reactor to do so – is a landmark achievement. It places the company as an early leader in a fast growing technology sector. The IMSR nuclear power plant is a transformative energy technology that is now one step closer to making a major contribution to the world’s growing demand for low-cost, clean and reliable energy.”
Terrestrial Energy was the first advanced reactor vendor to enter the regulatory process in Canada, and now the first to have its design assessed. The reactor’s design was aided by a Sustainable Development Technology Canada grant.
The IMSR power plant design is the “first and only” advanced reactor power plant project to enter the invitation-only stage of the U.S. Department of Energy’s loan guarantee program for construction financing support, with Idaho National Laboratory under consideration as a lead site.
Terrestrial Energy itself says it is studying the feasibility of a number of sites in North America, including Canadian Nuclear Laboratories at Chalk River, Ontario for building its first commercial power plant.
According to Terrestrial Energy, using molten salts rather than water to dissipate heat from the fission process is considered inherently safer, because it allows the reactor to operate at ambient atmospheric pressure. This lowers containment costs and enables cooling even when the system loses power.
Terrestrial Energy explains its IMSR® as a liquid-fuel reactor system, rather than a conventional solid-fuel system, using molten salt to dissipate heat. “Salts are thermally stable and excellent heat-transfer fluids, ideal for dissipating heat from the fission process simply and safely. In a molten salt reactor (MSR), salt provides a fluid medium to carry a nuclear fuel—in the case of the IMSR®, a low-enriched-uranium fluoride salt. The IMSR® provides simple, safe, and natural mechanisms for heat dissipation. It is a far superior system for the simple passive dissipation of fission heat. The use of a molten salt is at the heart of many engineering and commercial virtues of the IMSR®.
“An IMSR® power plant generates 400 MWth of thermal energy (190 MWe) with a thermal -spectrum, graphite-moderated, molten-fluoride-salt reactor system, fueled by low-enriched uranium (less than 5% 235U). It incorporates the approach to MSR design and operation researched, demonstrated and proven by the ARE and MSRE test reactors at Oak Ridge National Laboratory (ORNL); these were further developed under the DMSR program.”