The U.S. Department of Energy has selected four companies—Oklo Inc., Terrestrial Energy Inc., TRISO-X LLC, and Valar Atomics Inc.—to build pilot-scale advanced nuclear fuel production lines under its newly launched Fuel Line Pilot Program. These projects are intended to reinforce domestic supply chains for enriched fuels, reduce dependence on foreign sources, and support the broader Reactor Pilot Program targeting at least three reactors reaching criticality by July 4, 2026. Each company will bear the full cost of constructing, operating, and decommissioning their facilities, with the option to apply for high-assay low-enriched uranium (HALEU) via DOE’s availability program.
Sources: US Department of Energy, BusinessWire
Key Takeaways
– The DOE is accelerating development of a U.S. domestic nuclear fuel supply chain by selecting four firms for pilot-scale fuel fabrication lines, emphasizing private sector investment and cost responsibility.
– This move is tightly integrated with the Reactor Pilot Program, which aims to bring new advanced reactors online quickly; securing fuel availability is essential to that timeline.
– Selected firms must manage all costs and regulatory obligations themselves, but may access DOE’s HALEU program, enabling a quicker path toward licensing and deployment.
In-Depth
In mid-2025, the Department of Energy rolled out its Fuel Line Pilot Program, a bold step aimed at reshaping the U.S. nuclear fuel landscape. The logic is straightforward: advanced reactors demand novel fuels like TRISO or HALEU, and without domestic manufacturing capacity, deployment is bottlenecked. By mandating that private firms build and operate fuel lines—using DOE authorization without conventional NRC licensing for these pilot lines—the program seeks to catalyze a new nuclear supply chain built from the ground up.
The DOE has now selected four firms to carry forward the vision. Oklo Inc. will build three fuel fabrication facilities to support its Aurora and Pluto reactors (and possibly others). Terrestrial Energy Inc. will pursue a phased salt fuel fabrication line for its IMSR technology. TRISO-X LLC (in Oak Ridge, Tennessee) is tasked with creating a fuel lab to validate system integration toward a full commercial TRISO line. Valar Atomics Inc. will support TRISO fuel production for its high-temperature gas reactor ambitions. Each of these groups is already involved in the DOE’s Reactor Pilot Program, and the fuel line selection deepens their path from demonstration to deployment.
All selected firms are expected to carry the full burden of cost—construction, operation, decommissioning, and fuel sourcing. They also can apply for HALEU through DOE’s existing program, which supplies enriched uranium needed by many advanced reactors. By streamlining licensing at the pilot scale and providing a fast track toward eventual NRC approval, DOE hopes to bridge a critical gap: speeding from design to actual on-site deployment.
But challenges remain. The pilot lines must prove technological readiness, financial viability, and regulatory compliance. Access to HALEU is limited and tightly controlled, and the timeline is ambitious—DOE’s Reactor Pilot Program targets at least three new reactors being critical by July 4, 2026. That gives little room for delays at the fuel production stage. Moreover, since participants carry full risk, firms must balance innovation with capital discipline. Nevertheless, by pushing the private sector to build the fuel backbone of next-gen nuclear, the DOE is signaling a long-term commitment to national energy security, supply chain sovereignty, and the scaling of carbon-free power capacity.