The Special Nuclear Material Licence issued by the Nuclear Regulatory Commission (NRC) enables TRISO-X LLC to commercially manufacture fuel using high-assay low-enriched uranium (HALEU) at its first two commercial facilities – TX1 and TX2 – under an initial 40-year licence. The approval formally establishes TX-1 and TX-2 as the first new fuel facilities licensed by the NRC in over 50 years, X-energy said.
“Commercial-scale production of this fuel is key to enabling the deployment of advanced reactor designs,” NRC Chairman Ho Nieh said. “This licence represents an important milestone that supports the Department of Energy’s programme to accelerate deployment of nuclear technologies and deliver more power to the grid.”
TRISO fuel is composed of small spheres of enriched uranium that are coated with multiple layers of carbon and ceramic materials, forming a robust shell that can withstand high temperatures. HALEU contains between 5% and 20% of fissile uranium-235 – a higher enrichment than that found in typical uranium fuel used in today’s operating commercial reactors, which contains between 3.5% and 5% U-235.
The licence – under regulation 10 CFR Part 70 – authorises TRISO-X to receive, possess, process, and transport HALEU material throughout the complete fuel manufacturing cycle, encompassing HALEU feedstock receipt through final fuel production and shipment to SMR project sites under rigorous federal safety and security requirements. This allows TRISO-X to operate as a commercial fuel supplier, and authorises it to maintain continuous HALEU inventories and execute production campaigns sized to meet fleet deployment requirements, the company said.
TRISO-X submitted its licence application to the NRC in April 2022. The regulator’s review process included a safety and security review and an environmental review, and the NRC said the application was approved three months ahead of the published schedule “due to multiple efficiencies applied in the staff’s review processes.”
“Regulatory approval brings us one step closer to a resilient, American fuel supply for next-generation nuclear technology, advancing our energy security by closing a longstanding gap in the US nuclear fuel cycle,” TRISO-X President Joel Duling said. “Achieving this first-of-its-kind licence reflects the technical leadership and sustained diligence of the TRISO-X team, as well as a focused process with the NRC to complete the review three months ahead of schedule.”
Prior to receipt of special nuclear material and commencement of operations, the regulator will conduct a final inspection to confirm the facility is fully prepared for startup. This will include verification that equipment is ready for service, safety systems and items relied on for safety are installed and functional, and that programmes and procedures mandated in the licence have been put into place. It will also confirm that operating personnel are trained and qualified to safely begin operations.
Construction of the first facility, TX-1, began at the Oak Ridge Horizon Center last November. The facility will have an estimated output of 5 tonnes of uranium or 700,000 TRISO pebbles per year, enough fuel for up to 11 of X-energy’s Xe-100 high-temperature gas-cooled small modular reactors. A second facility – TX-2 – is currently in the design phase, and would scale TRISO fuel production capacity to support X-energy’s 11 GW commercial pipeline, equivalent to 144 Xe-100 reactors s as well as other SMR developers, the company said.













