Advanced reactor developer Oklo recently announced it is in advanced negotiations with the U.S. Department of Energy (DOE) to use surplus Cold War-era plutonium as fuel.
This is a significant development because the U.S. currently faces a major bottleneck in fuel for next-generation reactors. Most advanced designs require HALEU (High-Assay Low-Enriched Uranium), but domestic production is still very limited. The situation became more urgent after a 2024 law banned Russian uranium imports. Using surplus plutonium could serve as a vital 'bridge fuel,' easing this supply crunch and helping accelerate the deployment of new reactors needed to power things like AI data centers.
This negotiation didn't happen overnight; it's the result of a deliberate, multi-year causal chain. First, a major policy shift occurred in 2025 when the government directed the DOE to find ways to use its inventories of surplus plutonium. This changed the official approach from simply disposing of the material to actively recycling it.
Second, the government began rebuilding the necessary infrastructure. In March 2026, the DOE restarted the HB-Line facility at the Savannah River Site. This was a critical step, as it provides the physical capability to process plutonium into a usable form, like MOX-type fuel, for advanced reactors. Without this facility, any plan to use plutonium would have remained purely theoretical.
Third, the DOE created a formal pathway for private industry to get involved. In April 2026, it launched the Advanced Nuclear Fuel Recycling Program, inviting companies to submit proposals. This is the program through which Oklo is now negotiating. Oklo has also been preparing by forming a $2 billion partnership with European developer newcleo to build fuel infrastructure and collaborating with national labs and NVIDIA to use AI for faster fuel research and development. These actions positioned Oklo as a credible and well-prepared candidate for the DOE's initiative.
Ultimately, this move signals a practical shift toward a more sustainable nuclear fuel cycle in the U.S. By turning a legacy stockpile of waste into a valuable asset, it addresses both a national security liability and an energy sector bottleneck at the same time.
- HALEU: High-Assay Low-Enriched Uranium. A type of fuel required by many advanced nuclear reactor designs, enriched to between 5% and 20% uranium-235.
- MOX Fuel: Mixed Oxide fuel. A nuclear fuel that contains a mix of plutonium and uranium oxides. It's a way to recycle plutonium from military stockpiles or spent reactor fuel.
- HB-Line: A plutonium processing facility at the Savannah River Site in South Carolina. Its restart is key to converting surplus plutonium into fuel for advanced reactors.