DOE Taps Five Startups to Turn Cold War Plutonium Into Reactor Fuel

Key Takeaways

• Five startups including Oklo will negotiate to receive portions of 34 tons of Cold War plutonium for reactor fuel
• Energy Secretary Chris Wright previously sat on Oklo's board but resigned and divested shares before joining the administration
• Security experts warn that repurposing weapons-grade plutonium creates significant proliferation risks

The U.S. has spent decades trying to figure out what to do with 100 tons of plutonium left over from Cold War bomb production. Now, the Department of Energy thinks nuclear startups might be the answer.

On Tuesday, DOE announced it has selected five companies to enter negotiations for receiving a portion of 34 tons of plutonium previously earmarked for disposal. The startups, Oklo, Standard Nuclear, Shine Technologies, Flibe Energy, and Exodys Energy, are developing advanced reactors that could potentially run on the material.

“We are prioritizing technological agility to secure America's energy dominance against the massive power demands of the next decade.”

— Chris Wright, Energy Secretary

Wright's involvement comes with an asterisk. He previously sat on Oklo's board but resigned when he joined the Trump administration. He says he has divested his shares. Sam Altman, the OpenAI CEO, was Oklo's board chair following its merger with his acquisition company AltC. Altman resigned that position last year.

Why Plutonium Won't Just Go Away

Plutonium exists in nature, but weapons-grade plutonium is typically made by bombarding non-fissile uranium with neutrons. Once formed, the relevant isotope has a half-life of 24,000 years. The government cannot simply wait it out.

Storing this material costs money and creates security headaches. High-security facilities must guard against theft or sabotage indefinitely. The administration has shifted its view: rather than treating the stockpile as expensive waste, it now sees potential high-energy-density fuel for a new generation of reactors.

How These Startups Plan to Use It

Each company has a different approach to incorporating plutonium into their fuel cycle.

Oklo is developing a reactor that runs on traditional uranium fuel as well as plutonium. For the company, this material would help fuel its first reactors, solving a critical supply chain problem. UK-based Newcleo, one of Oklo's partners, has said it intends to build a mixed oxide (MOX) fuel fabrication facility nearby.

Exodys Energy is building a reactor designed to operate on MOX fuel, which blends uranium with plutonium. This approach is already used commercially in France.

Flibe Energy is working toward a reactor that would run on plutonium and other byproducts of fission reactors, potentially creating a closed fuel cycle that reduces overall waste.

The Failed MOX Plant

The U.S. has tried this before. A MOX fuel fabrication plant in South Carolina was supposed to convert weapons plutonium into commercial reactor fuel. The first Trump administration canceled that project after it blew through budgets and timelines.

France currently produces MOX commercially, showing the technology works. The question is whether American startups can succeed where the government's own facility failed.

Security Experts Sound Alarms

Not everyone is enthusiastic about handing weapons-grade plutonium to private companies.

“Countries have tried this before, and they concluded that, as nice as it would be to use that plutonium as fuel, it's really just a liability and we need to dispose of it permanently.”

— Scott Roecker, Vice President, Nuclear Threat Initiative

The concerns are straightforward. This plutonium came from nuclear weapons. Moving it from secure government facilities to startup operations creates transportation risks. Once distributed, it becomes harder to track and secure.

Online discussion has been polarized. Tech-focused communities on Reddit have applauded what some call an "Apollo-style" acceleration. Safety advocates worry about reduced Nuclear Regulatory Commission oversight in favor of direct DOE control.

What Happens Next

The five startups now enter advanced negotiations with the government. These talks will cover security protocols and transportation logistics. No plutonium will move until these agreements are finalized.

The timeline remains unclear. Building reactors and fuel fabrication facilities takes years. But for an industry that has struggled with fuel supply constraints, access to this plutonium stockpile could accelerate development significantly.

Frequently Asked Questions

Why is the U.S. giving plutonium to startups?

The government has spent decades trying to dispose of Cold War plutonium. These startups are developing reactors that can use it as fuel, potentially solving the disposal problem while generating power.

Which companies were selected for the DOE plutonium program?

The five startups are Oklo, Standard Nuclear, Shine Technologies, Flibe Energy, and Exodys Energy.

What is MOX fuel?

Mixed oxide fuel blends uranium with plutonium. It is currently produced commercially in France and can be used in certain reactor designs.

What are the security risks of repurposing weapons plutonium?

Critics worry that moving plutonium from secure government facilities to private operations creates transportation and tracking risks. The material originally came from nuclear weapons.

Did Chris Wright have ties to Oklo before becoming Energy Secretary?

Yes. Wright was previously on Oklo's board but resigned when he joined the Trump administration and says he has divested his shares.

Source: TechCrunch / Tim De Chant