Fueling Tomorrow’s Advanced Reactors


What is TRISO Fuel?

TRistructural ISOtropic (TRISO) coated fuels start with a uranium kernel, which is coated with three layers of pyrolytic carbon and one layer of silicon carbide. These coatings encapsulate all product radionuclei under all operating conditions. TRISO particles can be formed into numerous fuel element geometries thus supporting multiple advanced reactor designs and concepts.

TRISO Development Center

X-energy is currently manufacturing uranium oxide/carbide (UCO) based kernels, tristructural isotropic (TRISO) particles, and fuel pebbles at a 5,000-sq. ft. pilot fuel facility located at Oak Ridge National Laboratory (ORNL) as part of the DOE Advanced Reactor Concept 2015 Cooperative Agreement. This DOE Project allows X-energy to move from Pilot toward a FOAK fuel facility that serves advanced reactors with HALEU requirements, TRISO-based fuel forms, and Accident Tolerant Fuel.

X-energy is working to design, finance, and license their TRISO-X Commercial Fuel Fabrication Facility, scheduled to begin commercial-scale fuel production in the 2023-2024 timeframe.

Our mission is to be a U.S. Nuclear Regulatory Commission (NRC) regulated Category II TRISO-based fuel fabrication facility that supports the coming fleet of advanced reactors and helps extend operation of existing light water reactors (LWRs)

TRISO Coated Particle Fuel Enables Safety


Complement renewables on hybrid grids


Meltdown proof / Walkaway safe


On-site spent fuel storage


Less construction time