The Energy Department's Surplus Plutonium Utilization Program could turn roughly 20 metric tons of weapons-grade material into fuel for advanced reactors
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The U.S. Department of Energy selected five companies, including Oklo Inc. (NYSE: OKLO), to enter advanced negotiations over access to its Surplus Plutonium Utilization Program, which aims to convert Cold War-era weapons-grade plutonium into fuel for advanced nuclear reactors. The other four companies selected are Exodys Energy, SHINE Technologies, Standard Nuclear, and Flibe Energy, according to Reuters.
The negotiations are not yet finalized, according to CNN. Stockpiles of surplus plutonium — stored behind heavy security at weapons facilities across South Carolina, Texas, and New Mexico — carry a half-life of 24,000 years and can only be safely approached with protective gear, Reuters reported. In May 2025, Trump scrapped the bulk of an existing effort to dilute and bury the plutonium, issuing a directive to redirect the material toward fueling next-generation nuclear reactors.
Oklo said it plans to develop the fuel in partnership with newcleo, a European developer of advanced nuclear reactors. Within that arrangement, newcleo's role would center on providing fuel expertise and potential project capital, with Oklo taking the lead on plutonium utilization — all contingent on final agreements, regulatory approvals, and compliance with U.S. security and safeguards requirements, the company said. The partnership includes an investment of up to $2 billion via a newcleo-affiliated vehicle, subject to mutually acceptable documentation and industry conditions, Oklo said.
"Fuel supply constraints are a key throttle to advanced reactor development," Oklo co-founder and CEO Jacob DeWitte said in a statement. "This program creates a pathway to use existing surplus material as bridge fuel for advanced reactors to bring more reactors online sooner."
newcleo CEO and founder Stefano Buono said the program would reduce U.S. nuclear liabilities. In Feb. 2026, newcleo began pre-application engagement with the U.S. Nuclear Regulatory Commission for both an advanced fuel fabrication facility and a lead-cooled fast reactor design, Oklo said.
Oklo stock was up more than 5.5% to $69.51 per share on Tuesday.
The program has drawn criticism from Democratic lawmakers. A letter from Sen. Ed Markey of Massachusetts and Reps. Don Beyer of Virginia and John Garamendi of California warned that transferring weapons-usable plutonium to private industry would increase proliferation risks, according to CNN. Critics contend that American use of plutonium for civilian energy would hollow out Washington's moral standing when pressing other nations to refrain from the same, CNN reported.
Fuel access has been a central challenge for advanced reactor companies racing to meet surging electricity demand, driven in part by the growth of artificial intelligence data centers. Advanced reactors require more energy-dense fuel than conventional plants, and U.S. enrichment and fabrication capacity has atrophied for decades. The scramble to locate viable fuel for advanced reactors prompted DOE principal deputy assistant secretary of nuclear energy Mike Goff to coin the phrase "couch cushion exercise" — a reference to hunting everywhere possible for material that could be pressed into service quickly, according to CNN.
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