HALEU’s potential: HALEU, enriched to between 5 and 19.75 percent fissile uranium-235, occupies a middle ground between low-enriched uranium (enriched up to 5 percent U-235 and used in the U.S. power reactor fleet today) and highly enriched uranium (enriched above 20 percent U-235). While HALEU is not yet commercially available, several advanced reactor developers have created designs that would use the fuel, which, thanks to its increased U-235 content, holds potential for improved reactor economics and fuel efficiency. HALEU can be fabricated into different fuel forms, including TRISO fuel particles and solid metallic fuel, such as that proposed for TerraPower’s Natrium.
The plan: The ARDP requires applicants to “establish a plan by which they would obtain the fuel/special nuclear material needed for their projects.” TerraPower’s application proposes that, if selected for the ARDP, the company would work with Centrus to build commercial-scale capacity to produce HALEU and fabricate it into metal fuel assemblies. During the first year of the proposed collaboration, TerraPower and Centrus would initiate facility design and licensing and produce detailed plans and cost estimates. Specific terms of the agreement have not been disclosed.
In addition to creating HALEU production capacity, TerraPower and its partners plan to establish a new Category II metal fuel fabrication facility scaled to meet the needs of the Natrium demonstration program and equipped to produce lead test assemblies for the demonstration. Category II fuel fabrication facilities are authorized by the Nuclear Regulatory Commission to handle uranium at enrichments of 19.75 percent or less, and there are currently no Category II fabrication facilities in the United States.
What they said: “We are investing in American capability because it offers advantages related to assured domestic supply for the Natrium technology’s long-term commercialization prospects,” said Chris Levesque, TerraPower president and chief executive officer. “We are pleased that this effort supports broader Department of Energy goals with regard to HALEU production and market deployment of domestic advanced reactor technology.”
Daniel B. Poneman, Centrus president and CEO, said, “By catalyzing commercial-scale HALEU production, the proposed investment would put America in the leadership position when it comes to fueling the advanced reactors of tomorrow. This partnership with TerraPower would enable us to expand beyond demonstration scale, and we have more than enough room at the Ohio plant to continue expanding uranium enrichment and fuel fabrication capability as demand grows and the market matures.”
Investing in Centrus: Centrus is currently working under a three-year, $115-million cost-shared contract with the DOE to deploy 16 of its AC-100M centrifuges at its Piketon, Ohio, facility to demonstrate HALEU production. Centrus and has also applied to the NRC for a license to produce HALEU.
Once the demonstration is complete in mid-2022, TerraPower and Centrus would work to expand the facility. According to TerraPower, the Natrium proposal includes private investment beyond the 50 percent cost-share minimum required by the DOE for ARDP demonstration reactors. This additional investment is “to ensure that both the reactor can be commercialized within five to seven years and that new HALEU production capacity can be built,” according to TerraPower, and “can benefit the large number of advanced reactor developers planning on using HALEU.”
The U.S. Nuclear Fuel Working Group report issued by the DOE in April 2020 identified HALEU production capability as a key priority and anticipated that the technology “can be adopted by the private sector for commercialization and deployment after the three-year [cost-shared contract], should the demonstration be successful and demand materialize.” TerraPower is signaling its readiness to step into that role. Bills including support for HALEU production have received bipartisan backing in Congress.
