The US Department of Energy (DOE's) Advanced Research Project Agency-Energy (ARPA-E) has awarded Moltex Energy USA $2.55 million to develop technologies to reduce Stable Salt Reactor (SSR) construction timelines to under three years.
The funding will be used to develop composite structural technologies (COST) for the reactor, which Moltex says will bring the Stable Salt Reactor-Wasteburner (SSR-W) - the first variant of the SSR being developed by the company - closer to market and global roll-out.
The aim of ARPA-E is to advance high-potential, high-impact energy technologies that are too early for private-sector investment. The award to Moltex is part of ARPA-E's MEITNER (Modelling-Enhanced Innovations Trailblazing Nuclear Energy Reinvigoration) programme, which, "seeks to identify and develop innovative technologies that can enable designs for lower cost [and] safer advanced nuclear reactors".
Moltex will collaborate with Argonne National Laboratory (ANL), Oak Ridge National Laboratory (ORNL), the Electric Power Research Institute (EPRI), Purdue University and Vanderbilt University on the SSR, exploiting innovative technologies such as advanced structural composites and coatings to enable rapid construction.
The SSR is a molten salt reactor, which uses fuel dissolved in a molten fluoride or chloride salt, that also functions as the reactor's coolant. The molten salt fuel is
held in vented tubes bundled into fuel assemblies which make up the reactor's core modules. Each 150MW module will be factory built, containing a support structure for the fuel assemblies, heat exchangers and other pumps and controls. The rectangular core modules are held in a larger tank filled with a molten salt coolant. A second similar coolant salt system takes heat from the primary coolant salt.
In 2018, Moltex signed an agreement with the New Brunswick Energy Solutions Corporation and NB Power to build a demonstration SSR-W at Point Lepreau in Canada. The second-generation SSR is envisaged to use uranium fuel, is aimed at those countries which do not have existing nuclear reactors and therefore have no waste to burn. The company also sees a thorium breeder version of the reactor.
"If we are to displace fossil-fuelled generation fast, the entire plant - from reactor to final construction and operation - needs to consider the real-world financing, economic issues, operating practicalities and lead times of nuclear new build," said Adam Owens, principal investigator of Moltex's COST. He added: "This project demonstrates SSR-W as an economically practical solution to climate change in the urgent timeframes required, in the highest impact areas for global decarbonisation in the 2030s, rather than the 2040s or 2050s."
Photo: The Stable Salt Reactor (Credit: Moltex Energy)