US develops advanced nuclear reactor concept with high-temp cladding

General Atomics, supported by the US Department of Energy (DOE), has completed the conceptual design phase of its 44 MW Fast Modular Reactor (FMR), a helium gas-cooled fast reactor employing silicon carbide-wrapped high-assay low-enriched uranium (HALEU) fuel. This advanced fuel cladding is engineered to tolerate temperatures twice as high as those in conventional light-water reactors, enhancing safety and performance. The FMR is designed as a compact, modular system occupying about 0.2 acres, capable of factory manufacturing and on-site assembly. Notably, it can operate with an air-cooling system, eliminating the need for water and enabling deployment in arid or remote locations unsuitable for traditional water-cooled reactors. The project has progressed with the submission of licensing documents to the US Nuclear Regulatory Commission (NRC), including Principal Design Criteria and Quality Assurance plans, with pre-application materials docketed to support future licensing. Prototype fuel rods matching final design specifications are undergoing irradiation testing at