DOE Allocates Second Round of HALEU Fuel to Three U.S. Nuclear Companies

The U.S. Department of Energy (DOE) has unveiled three more companies to which it will allocate high-assay low-enriched uranium (HALEU) under conditional commitments in a bid to support advanced reactor development and domestic fuel production.

The Aug. 26 announcement marks the second round of allocations under DOE’s HALEU Availability Program but it links to two initiatives launched over the past few weeks under recent executive orders. These include the Reactor Pilot Program, created under Executive Order 14301 to achieve criticality in at least three advanced reactor designs by July 4, 2026, and the Fuel Line Pilot Program, established under Executive Order 14299 to fast-track construction of nuclear fuel production lines and expand TRISO capacity.

The DOE said the new allocations will go to Antares Nuclear Inc. for a microreactor demonstration targeting first criticality by July 2026 under the Reactor Pilot Program; Standard Nuclear Inc. to expand TRISO manufacturing capacity as part of the Fuel Line Pilot Program; and Abilene Christian University/Natura Resources LLC for a molten salt research reactor already under construction in Texas.

Second Round of Allocations for a Crucial Nuclear Fuel Material

The three companies join five recipients from DOE’s first HALEU allocation announced in April, bringing the total to eight companies receiving government-backed fuel support. As POWER reported, in the initial round, DOE issued conditional commitments to TRISO-X, TerraPower, Kairos Power, Radiant Industries, and Westinghouse Electric Co. Initial selections largely reflected awardees under the DOE’s 2020-launched Advanced Reactor Demonstration Program (ARDP)—including Pathway 1 developers and risk-reduction participants—along with companies preparing projects for the agency’s DOME test bed at Idaho National Laboratory.

At the time, DOE noted that it received HALEU requests from 15 companies and for its first round, it identified five companies that met prioritization criteria and at least three that required fuel delivery in 2025. The DOE on Tuesday said the second round of allocations reflects the same prioritization framework, though selections appear more deliberately designed to support the DOE’s June-initiated Reactor Pilot Program and firming up a domestic TRISO fuel line.

“President Trump has prioritized jumpstarting a true nuclear energy renaissance, and the Department of Energy is doing everything within its power to achieve this ambitious agenda, including increasing access to materials needed to fabricate advanced nuclear fuels,” said U.S. Secretary of Energy Chris Wright in a statement on Tuesday. “We’re reducing our dependence on foreign-sourced minerals while giving the private sector the boost it needs to succeed.”

The DOE now plans to “initiate the contracting process to allocate the material to the three companies, some of which could receive their HALEU later this year,” it said. “The allocation process is ongoing, and DOE plans to continue HALEU allocations to additional companies in the future.”

The HALEU allocations stem from the HALEU Availability Program (HAP), which the DOE established under the Energy Act of 2020 to ensure access to HALEU for civilian research, development, demonstration, and early commercial deployment. While the existing U.S. fleet runs on uranium fuel enriched up to 5% with uranium-235 (U-235), HALEU is a nuclear material enriched between 5% to 20%. The material has several uses in fuel for advanced reactors—such as fast reactors, molten salt reactors, and microreactors— including for TRISO fuel. HALEU may also be used in operating reactors (enriched between 5% and 10%) to boost their performance.

Global HALEU production remains severely constrained. For now, Russia’s Rosatom subsidiary TENEX holds a commercial monopoly status, though several countries have acknowledged that its dominance faces imminent challenges. China is also reportedly developing infrastructure to produce HALEU.

In total, as outlined by the HALEU Allocation Process finalized in September 2024, the DOE intends to make 21 metric tons of HALEU available by June 30, 2026, to support near-term industry needs. Under the FY 2024 National Defense Authorization Act, Congress directed the DOE to make the 21 metric tons of HALEU available on a set schedule: 3 metric tons by Sept. 30, 2024; 8 metric tons by Dec. 31, 2025; and 10 metric tons by June 30, 2026.

To support immediate needs, the DOE will likely draw HALEU from DOE- and National Nuclear Security Administration (NNSA)-managed surplus stockpiles located at several federal sites, including the Y-12 National Security Complex in Tennessee, the Savannah River Site in South Carolina, and the Idaho National Laboratory.

In parallel, the DOE is also supporting limited HALEU production from Centrus Energy’s American Centrifuge Plant cascade in Piketon, Ohio. Centrus in October 2023 kicked off HALEU enrichment operations, delivering its first 20 kilograms (kg) of HALEU in November 2023. In June, Centrus reported it produced and delivered 900 kg of HALEU to the DOE, completing Phase II of its pioneering enrichment contract with the agency.

Antares Nuclear: HALEU for Microreactor

Antares Nuclear, a California-based company founded in 2023, will use its HALEU allocation for an advanced microreactor design, likely based on its Antares R1 design, a kilowatt-class microreactor designed to generate 200-300 kW per unit. The reactor uses HALEU TRISO fuel in a prismatic graphite core with sodium heat pipes for passive heat transfer, eliminating moving parts for enhanced reliability. The system features integrated shielding using tungsten and boron carbide, graphite and boron carbide control drums, and a nitrogen Brayton cycle for power conversion at less than 300 psi.

Antares says it has so far secured more than $38 million in venture funding, a $3.75 million U.S. Air Force award to accelerate its microreactor design, and an $8 million seed round from venture capital funds to support early R&D. In July, notably, the company said it signed two new contracts with Idaho National Laboratory (INL). One is a $40-million-plus agreement to build and demonstrate the Antares R1 microreactor in an existing INL facility. “This agreement puts Antares in a position to be America’s first privately funded electricity producing advanced reactor as soon as 2027,” it said. The second contract advances plans to establish a permanent INL testing facility where Antares can operate its microreactors on site prior to commercial or military deployment.

On Aug. 12, DOE formally selected Antares Nuclear Inc. as one of 11 recipients under the newly launched Nuclear Reactor Pilot Program. Antares joins a diverse list of advanced nuclear technlogy developers, including Aalo Atomics, Atomic Alchemy, Deep Fission, Last Energy, Natura Resources, Oklo (two projects), Radiant Industries, Terrestrial Energy, and Valar Atomics. “The program aims to leverage DOE’s authority to expedite the research and development of advanced nuclear reactor technologies with the larger goal of reaching criticality for at least three advanced nuclear reactor concepts located outside of the national laboratories by July 4, 2026,” the DOE has explained. As POWER has reported, the crucial point is that the program shifts authorization for these first-of-a-kind demonstrations from the Nuclear Regulatory Commission to the Department of Energy itself, a move intended to compress timelines, de-risk early-stage investment, and create a pathway for private developers to prove new reactor designs on an accelerated schedule.

Standard Nuclear: Building a TRISO Fuel Line

Standard Nuclear, a Tennessee-based company founded in 2024, has positioned itself as the nation’s only independent, reactor-agnostic manufacturer of tristructural isotropic (TRISO) fuel. The company emerged from stealth on June 11, 2025, announcing $42 million in funding led by Decisive Point with participation from Andreessen Horowitz, Washington Harbour Partners, Welara, Fundomo, and Crucible Capital. At the time, executives emphasized that Standard Nuclear’s model—focused exclusively on fuel rather than reactor development—is intended to strengthen the advanced reactor supply chain by providing a reliable, independent source of TRISO at an industrial scale.

The company’s operations are centered at a 19,000-square-foot commercial-scale facility on the former K-25 site in Oak Ridge, Tennessee. The site houses fully permitted radiological facilities and has already produced TRISO fuel for government and commercial customers. By midyear, Standard Nuclear reported $5 million in signed contracts and more than $100 million in non-binding orders for 2027. Customers span advanced reactor startups and government agencies, including DOE national laboratories and the Department of Defense.

On Aug. 5, DOE’s Office of Nuclear Energy selected Standard Nuclear for its new Fuel Line Pilot Program, created to accelerate fuel readiness for the agency’s reactor demonstration agenda. The DOE cited the company’s existing, privately funded manufacturing line as the basis for its selection. Under the program, Standard Nuclear is slated to expand, build, and operate advanced fuel fabrication facilities for TRISO fuels in both Tennessee and Idaho by mid-2026.

Executives told POWER in June that the company was created to close what they see as the most immediate constraint on advanced reactor deployment: the absence of an independent, industrial-scale TRISO fuel supply. While multiple startups are advancing new reactor designs, most rely on small, in-house fuel lines or laboratory-scale production. Standard Nuclear’s strategy is to take TRISO out of boutique production and manufacture it at commercial volumes, reducing cost through scale and ensuring availability for any developer. In their view, the first advanced reactors to demonstrate will be those that secure fuel, not just those that finish a design.

Abilene Christian University/Natura Resources: Molten Salt Research Reactor

Natura Resources, founded in 2020 by oil and gas executive Douglass Robison, is pursuing what would be the first liquid-fueled molten salt reactor built in the United States. Robison, who previously led ExL Petroleum through the shale boom, launched the company with a research-driven structure anchored at Abilene Christian University (ACU). Through the Natura Resources Research Alliance—which includes ACU, Texas A&M University, the University of Texas at Austin, and Georgia Institute of Technology—the venture combines private backing with academic capabilities to advance molten salt reactor technology while training the next generation of nuclear engineers.

The team’s first project, the Natura MSR-1, is a 1-MWt test reactor designed to operate with a fuel salt mixture of lithium fluoride, beryllium fluoride, and uranium tetrafluoride (LiF-BeF₂-UF₄). The compact vessel, built to ASME Section III standards from Type 316H stainless steel, is engineered with passive safety systems that allow the fuel salt to drain into a tank within a minute in the event of an abnormal condition, with decay heat removable indefinitely. In September 2024, the Nuclear Regulatory Commission (NRC) approved a construction permit for the unit on ACU’s campus, making it the first liquid salt-fueled reactor licensed in U.S. history.

The HALEU allocation announced in August is intended to fuel that research reactor, which ACU expects to begin operating once it secures an NRC operating license. Executives said they plan to file the application in 2025. Beyond the Abilene project, Natura Resources has outlined two additional Texas deployments: a unit in the Permian Basin in partnership with Texas Tech University and the Produced Water Consortium, and a second at Texas A&M University’s RELLIS campus. The company has signaled that successful demonstration of the ACU research reactor would pave the way for commercial deployment of molten salt systems by 2030.

—Sonal Patel is a POWER senior editor (@sonalcpatel, @POWERmagazine).