DOE’s ARPA-E selects eight transuranic fuel development projects

The Department of Energy's Advanced Research Projects Agency-Energy (ARPA-E) division has chosen eight research projects to receive funding as part of its High-Performance Optimized Recycled Nuclear Isotopes for Gen IV Reactors (HORNIG) program.

The program, announced in April, seeks to advance Executive Order 14302, "Reinvigorating the Nuclear Industrial Base," by supporting projects that will develop fuel technology for advanced nuclear reactors. The projects selected for HORNIG will explore ways to repurpose materials from used nuclear fuel inventories-specifically the transuranic waste elements derived from nuclear weapons production, including plutonium-in the domestic production of fuel for commercial reactors.

In its October 29 announcement, ARPA-E stated that the projects in the HORNIG program are slated to receive a combined total of up to $50 million in funding. Currently the grant amounts total almost $45 million; the largest awards are for $7 million each.

Acceleration and momentum: The development and qualification of a new type of nuclear reactor fuel can take more than a decade, but the HORNIG program aims to shorten that time to under seven years, according to an ARPA-E spokesperson. The spokesperson added, HORNIG will facilitate expedited fuel qualification because its projects will combine fuel manufacturing, modeling, and testing early in the process, and noted that existing safety and regulatory guidelines will apply to these projects.

Additionally, HORNIG will build on the findings of another ARPA-E program, Converting UNF Radioisotopes Into Energy (CURIE). Launched in 2022, CURIE supports research into techniques to recover reusable material, including TRU elements, from used nuclear fuel, the goal being to send less waste for permanent disposal while increasing the amount of domestically produced fuel available.

HORNIG is presented as the next step of a sequence; its projects would produce advanced reactor fuel using materials recovered with CURIE-developed techniques. However, of the eight participants whose projects were chosen for HORNIG, only one-Idaho National Laboratory-also has advanced a project through CURIE.

The organizations: Each of the eight organizations named in today's announcement already is extensively involved in various nuclear fuel projects. The projects they submitted for HORNIG cover a range of advanced reactor fuel technologies, including molten salt fuels and TRISO fuel particles.

Below are summaries of each participant's plans for the program along a brief background.

Westinghouse, based in Cranberry Township, Pa., was awarded $7,000,000 for its project "PowerBlock: Additively Manufactured Metallic Fuel." According to ARPA-E, Westinghouse will develop a process using laser powder bed fusion to produce this fuel. Westinghouse describes, PowerBlock as a technology "designed to advance the traditional nuclear fuel assembly, targeting 24-month fuel cycles at thermal power levels above 4,200 megawatts." This fuel will be designed for use in both the current fleet and advanced reactors. Already a major fuel supplier, Westinghouse supplies 40 percent of the global nuclear fleet (though none of this current supply is metallic fuel), the company said. It manufactures its fuel at three sites: one in Sweden, one in the United Kingdom, and one in South Carolina, where the company is currently planning a significant expansion.

Oregon State University, in Corvallis, was awarded $7,000,000 for its project "TRU-Nitride Fuel for Advanced Reactors." According to ARPA-E, the university will fabricate recycled transuranic-bearing nitride fuel using a low-temperature process. Oregon State already is a hub for nuclear research-it operates a TRIGA reactor and maintains several other test facilities and nuclear-related laboratories. Likely to be most relevant among these facilities is its Hydro-Mechanical Fuel Test Facility, which the university is currently using for uranium-molybdenum fuel qualification work.

Idaho National Laboratory, in Idaho Falls, was awarded $7,000,000 for its project "Irradiation of Molten Plutonium Actinide Chloride Fuels and Testing (IMPACT)." According to ARPA-E, INL will develop and test a chloride fuel salt containing recycled TRU elements for use in molten salt reactors. This project adds to dozens of ongoing fuel-related projects at INL.

Standard Nuclear, based in Oak Ridge, Tenn., was awarded $6,999,984 for its project "Mixed Oxycarbide (MCO) TRISO: Fueling Advanced Reactors with Recycled Transuranic and Uranium Feedstock." The TRISO manufactured through this project will be targeted for use in high-temperature gas reactors. Standard Nuclear was founded in 2024 and acquired the assets of Ultra Safe Nuclear following the latter's bankruptcy. Its fuel fabrication plans were selected for fast-tracking through the DOE's Fuel Line Pilot Program last year. It also has been allocated HALEU by the DOE. Currently, the company is building two TRISO production facilities-one in Idaho and one in Tennessee-which are progressing through DOE authorization.

Oklo, based in Santa Clara, Calif., was awarded $6,842,989 for its project "Fabrication of Optimized Recycled Fuel for Gen IV reactors from Electrorefiner Product (FORGE)." According to ARPA-E, the company "will develop transuranic-bearing U-TRU-Zr metallic fuel for use in sodium-cooled reactors." This fuel could assumedly be used for Oklo's flagship reactor design, the Aurora Powerhouse, a liquid metal-cooled, metal-fueled fast reactor. This newest collaboration with the DOE adds to an already complex network of ties between the company and agency. Oklo has pursued three projects through the Reactor Pilot Program, is a participant in the Nuclear Energy Launch Pad, and is developing a project through the Fuel Line Pilot Program. Its flagship fuel project is the Aurora Fuel Fabrication Facility at INL.

Texas A&M University, in College Station, was awarded $5,377,799 for its project "Thorium-Based Transuranic Burner Molten Salt Fuel Systems (TB²-MSR)." According to ARPA-E, the university will "develop and test a liquid, thorium-based nuclear fuel salt" that incorporates transuranic elements from used fuel for use in molten salt reactors. Texas A&M previously partnered with Clean Core Thorium Energy and INL to manufacture thorium-uranium fuel pellets. It also recently partnered with Quantum Leap Energy on uranium conversion research. Outside of fuel, Texas A&M has invited four advanced reactor developers to site projects on its RELLIS campus and has signed a lease with Terrestrial Energy to that end.

Sandia National Laboratories, in Albuquerque, N.M., received $3,381,128 for its project "Transuranic Reactor-Fuel Pathways for Sociotechnical Analysis, Technoeconomics, and Harmonization," which will focus on analyzing the rest of the HORNIG fuel concepts by providing "uncertainty-aware decision support capability associated with scaling [TRU] fuel production," according to ARPA-E. Sandia is one of the key nuclear research hubs in the United States on the fronts of both energy and fuel.

Exodys Energy, based in New York, N.Y., was awarded $1,300,792 for its project "Integrated TRU Fuel Cycle Analytics: Front-End Feedstock, Techno-Economics, and Deployment Pathways." Like Sandia's, Exodys's project will focus on evaluating the rest of the HORNIG fuel concepts. According to ARPA-E, the start-up (founded in 2023) will "develop a common framework for evaluating transuranic fuel feedstocks, fuel-cycle costs, transportation, and deployment requirements across" the program. Generally, Exodys is focused on fuel recycling and is one of five companies being considered for receipt of plutonium from the DOE.