The US Department of Energy (DOE) announced an approximately $150-million cost-shared award with American Centrifuge Operating (ACO), a subsidiary of Centrus Energy Corp, to demonstrate the ability to produce high-assay low-enriched uranium (HALEU)—a crucial material needed to develop and deploy advanced reactors in the United States.

HALEU is uranium that has been enriched so that the concentration of the fissile isotope U-235 is between 5 and 20 percent of the mass of the fuel. This is higher than the 3 to 5 percent U-235 concentration, or “assay,” of Low-Enriched Uranium that fuels the existing fleet of light water reactors. Source: Centrus Energy

HALEU fuel has advantages that improve reactor performance. The higher concentration of fissile U-235 means the fuel assemblies and reactors can be smaller, and reactors don’t need refueling as often; many small modular reactor (SMR) and microreactor designs will run on HALEU. HALEU can also reduce the volume of waste generated.

HALEU is not currently available at commercial scale from domestic suppliers, a situation that could significantly impact the development and deployment of US advanced reactors. Advancing domestic capability to produce HALEU will set the stage for larger, commercial-scale HALEU production in the US.

The award includes a $30-million cost share during the first year to start up and operate 16 advanced centrifuges in a cascade at an enrichment facility in Piketon, Ohio. American Centrifuge Operating will complete the final steps of centrifuge assembly and clear an operational readiness review to start up the demonstration cascade.

ACO will meet the demonstration requirements by enriching uranium hexafluoride gas to produce 20 kilograms of 19.75% enriched HALEU by 31 December 2023. ACO will then continue production in 2024 at an annual production rate of 900 kilograms of HALEU per year, subject to appropriations, with additional options to produce more material under the contract in future years. Annual Congressional appropriations will inform the duration of the contract based on the availability of funding.

DOE projects that more than 40 metric tons of HALEU will be needed before the end of the decade, with additional amounts required each year, to deploy a new fleet of advanced reactors. The cascade demonstration program is intended to address near-term HALEU needs and will be used to support fuel qualification testing and DOE-supported advanced reactor demonstration projects.

This latest award builds on DOE’s three-year cascade demonstration program with American Centrifuge Operating, to manufacture and demonstrate the centrifuge enrichment cascade. The cascade was assembled at the Department’s enrichment facility in Piketon, OH, which is currently the only US plant licensed to produce HALEU. Centrus completed manufacture and most of the assembly but did not install the centrifuge rotors into the demonstration cascade while the Department conducted this competition.

AC-100 centrifuge cascade at American Centrifuge Plant in Piketon, Ohio.

DOE is pursuing multiple pathways to produce HALEU through its HALEU Availability Program authorized by the Energy Act of 2020 to meet this pressing need. Following the HALEU demonstration, the centrifuge technology used at the facility will be available for commercial deployment.

In addition to commercial needs, the US Department of Defense’s Project Pele is working to build a prototype HALEU-fueled mobile microreactor in the next few years that can be transported by truck, train, or plane.