X-energy is the inventor of the Xe-100 high temperature gas cooled small modular reactor (SMR). They announced on April 4th that their wholly owned subsidiary, TRISO-X LLC, has selected the Horizon Center Industrial Park in Oak Ridge to site their TF3 plant which will initially produce eight tons of fuel per year. This is enough to provide fuel for twelve Xe-100s. The commercial facility’s cross cutting design will enable the manufacture of fuel for any number of advanced or small nuclear reactors based on Tristructural isotropic (TRISO) fuel. Construction is expected to begin this year with a start up as soon as 2025.
TRISO fuel particles consist of a “kernel” of uranium oxycarbide (or uranium oxide) surrounded by layers of carbon and silicon carbide. This provides containment for fission projects and is stable up to very high temperatures. Fuel for X-energy’s Xe-100 SMR consists of spherical pebbles which are each embedded with eighteen thousand TRISO particles. Each fuel pebble is about two and a half inches in diameter.
TF3 will be the first US Nuclear Regulatory Commission (NRC) Category II-licensed TRISO-based fuel fabrication facility. It will utilize uranium enriched less to less than twenty percent uranium-235 to manufacture nuclear fuel products for a variety of advanced and SMRs. It will also make specialty fuels for nuclear space projects.
In October 2020, the U.S. Department of Energy (DoE) selected X-energy as one of two recipients to receive funding under its Advanced Reactor Demonstration Program (ARDP) for the construction of a demonstration plant that can be operatioinal in seven years.
Under the project, X-energy is to deliver a commercial four-unit power plant based on the Xe-100. In addition, they are to provide a commercial-scale TRISO fuel fabrication facility. In April 2021, Energy Northwest, Grant County Public Utility District and X-energy formed the Tri-Energy Partnership for the purpose of constructing a plant based on the Xe-100 design at Energy Northwest's existing Columbia nuclear site in Washington state.
Pete Pappano is the President of TRISO-X. He said, “The Department of Energy calls TRISO the most robust nuclear fuel on Earth. TRISO is a technology that's been developed and improved over 60 years. Our facility will bring this game-changing fuel to market, beginning with a proprietary spherical fuel pebble for X-energy's Xe-100 reactor and its utility partner Grant County Public Utility District, in Washington state.”
TR3 will also be used to continue to support government funded projects. These include mobile reactors for the military or nuclear space projects. TRISO-X is already operating two facilities at Oak Ridge. The first is the TRISO-X Pilot Facility, located inside the Oak Ridge National Laboratory. The second is the TRISO-X Research and Development Center in the Centrus Technology Manufacturing Center. TF3 is expected to generate more than four hundred new jobs in the Oak Ridge area and attract in the neighborhood of three hundred million dollars of investments.
TRISO-X submitted its license application to the NRC on April 6th. This application is the first of its kind for a facility dedicated exclusively to handling and processing uranium of such enrichment. The license application took about three years to write. It costs almost twenty million dollars and the NRC’s review process is expected to take from two to three years. If the application is approved, TF3 will become the first 10 CFR 70 Category II licensed fuel facility in the U.S.
The NRC review and TRISO-X’s interaction with the NRC over this period are part of X-energy’s cooperative agreement with ARDP. Andrew Griffith is the U.S. acting assistant secretary for Nuclear Energy. He said that the licensing milestone is a “critical step” towards achieving the program’s goals.