New US nuclear fuel facilities target 5-metric-ton uranium production for advanced reactors

US-based Standard Nuclear has completed primary construction and obtained initial regulatory clearance for two manufacturing plants in Tennessee and Idaho. The parallel milestones advance the company’s efforts to increase domestic production capacity for tri-structural isotropic (TRISO) nuclear fuel, which is an advanced material designed for next-generation nuclear reactors. The newly built plants, designated SN-TN and SN-ID, rely on a standardized architecture intended to eliminate design variations across deployment sites. By standardizing component layouts, equipment integration, and vendor specifications, the company replicates full production lines without requiring site-specific engineering overhauls. This modular framework reduces first-of-a-kind design risks and limits required capital outlay during capacity expansion. Each facility is initially rated to add 1 metric ton of uranium (MTU) per year in output capacity. Once engineers fully ramp up both sites, total combined throughput from these identical units will reach up to 5 MTU annually. Technical teams will conduct initial system start-up, cold commissioning, and final operational licensing throughout the summer months. Alongside construction progress, the US Department of Energy (DOE) reviewed and approved the Preliminary Documented Safety Analyses for both installations. Upon final authorization, the processing lines will operate under Hazard Category 2 nuclear safety standards. Technical contributions from Idaho National Laboratory supported the safety modeling needed to fulfill DOE safety criteria. Standard Nuclear manufactures TRISO particles, a fuel form engineering structure that replaces conventional metal-clad fuel rods. Each millimeter-sized TRISO particle consists of a High-Assay Low-Enriched Uranium (HALEU) core surrounded by three specialized layers that serve distinct physical functions. The innermost layer is a porous carbon buffer that absorbs recoil energy from fission fragments and provides internal clearance to collect gaseous fission products. Surrounding this buffer are inner and outer pyrolytic carbon layers that provide structural stability and prevent gas migration. Sandwiching these is a silicon carbide layer, which acts as a high-strength pressure vessel capable of withstanding extreme internal pressures and temperatures exceeding 1,600°C without degrading. Because this multi-layered ceramic shell retains fission products directly inside the particle, it satisfies the “functional containment” standard defined by the Nuclear Regulatory Commission. This physical property enables high-temperature gas-cooled reactors and microreactors to operate safely without needing massive secondary containment structures. The two new facilities expand an existing production footprint rooted in Oak Ridge, Tennessee. At its primary SN-0 site, Standard Nuclear currently produces TRISO fuel at a maximum capacity of 0.5 MTU annually. In January, that site accepted the first physical delivery of HALEU feedstock distributed through a DOE supply initiative. This made Standard Nuclear the first commercial firm to secure both regulatory approval and physical custody of HALEU for processing. To diversify its manufacturing capabilities, Standard Nuclear is assembling a separate production line in Washington state through a joint venture with Framatome. That effort taps Framatome’s existing Nuclear Regulatory Commission license to streamline the regulatory transition from fuel fabrication to commercial shipment. By operating reactor-agnostic processing facilities, Standard Nuclear supplies standardized TRISO fuel across diverse commercial reactor designs, remote terrestrial installations, defense platforms, and space-based radioisotope power systems. With physical construction now complete in Tennessee and Idaho, engineering teams are conducting system integration testing, finalizing regulatory steps, and matching production schedules to utility delivery timelines. Recommended ArticlesGet the latest in engineering, tech, space & science - delivered daily to your inbox.An active and versatile journalist and news editor. He has covered regular and breaking news for several leading publications and news media, including The Hindu, Economic Times, Tomorrow Makers, and many more. Aman holds expertise in politics, travel, and tech news, especially in AI, advanced algorithms, and blockchain, with a strong curiosity about all things that fall under science and tech.