X-energy Reactor Company, along with its subsidiary TRISO-X LLC, has begun above-ground construction of its advanced nuclear fuel fabrication facility, TX-1, in Oak Ridge, Tennessee. This marks a major milestone for what is expected to be the first facility in the United States dedicated exclusively to manufacturing fuel for advanced small modular reactors (SMRs).
The TX-1 facility will produce X-energy’s proprietary tristructural-isotropic (TRISO) fuel, which is designed for the company’s Xe-100 reactor technology. The fuel will support X-energy’s initial Xe-100 deployment in partnership with Dow Inc. at the Texas Gulf Coast under the Advanced Reactor Demonstration Program, as well as future projects and customers.
The start of vertical construction follows the transition from site development to full-scale building construction. Earlier this year, X-energy awarded a $48.2 million contract to Clark Construction Group for the core and shell of the 214,812-square-foot facility. Construction of this phase is expected to be completed by mid-2026.
Once operational, TX-1 will become the first Category II nuclear fuel fabrication facility licensed by the US Nuclear Regulatory Commission and the first new fuel fabrication plant built in the country in more than 50 years. The facility is expected to produce up to five metric tons of uranium per year, equivalent to approximately 700,000 TRISO fuel pebbles, enough to supply fuel for as many as 11 Xe-100 reactors annually. TRISO-X continues to work closely with the NRC and anticipates regulatory approval by May 2026.
In parallel with construction, X-energy has launched confirmatory qualification testing of its TRISO-X fuel at Idaho National Laboratory’s Advanced Test Reactor. Conducted in collaboration with the US Department of Energy and the National Reactor Innovation Center, the 13-month testing program will evaluate fuel performance under a wide range of operating conditions. This represents the most rigorous testing ever conducted on a commercially produced SMR fuel form.
X-energy is also advancing multiple Xe-100 reactor projects across the United States. These include a four-unit plant at Dow’s UCC Seadrift Operations site in Texas and the Cascade Advanced Energy Facility with Energy Northwest, in collaboration with Amazon. The Amazon partnership aims to bring more than five gigawatts of new power capacity online by 2039.
The launch of vertical construction at TX-1 reinforces X-energy’s role in advancing next-generation nuclear energy and strengthening the domestic supply chain for clean, reliable, and zero-carbon power.
