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Exclusive: Transmutex raises $23M to recycle nuclear waste

Illustration of a recycling bin with green radioactive drips around the top.

Illustration: Gabriella Turrisi/Axios

Nuclear engineering startup Transmutex has raised $23.2 million to produce energy and nuclear fuel from radioactive waste.

Driving the news: Surging energy demand from data centers and AI development has reignited interest in the need to build more nuclear power plants.

How it works: Most nuclear reactors use uranium-235, an expensive isotope that can also make a nuclear weapon.

  • Transmutex says it's designed a particle accelerator and fuel system that can run on cheaper and safer metals such as thorium.
  • The design converts nuclear waste into fresh reactor fuel while generating a modest amount of energy.

What they're saying: "Our primary purpose is not to produce electricity," CEO Franklin Servan-Schreiber tells Axios.

  • "Our primary purpose is to destroy the long-lived waste that is plaguing the industry and to transform it into new fuel that will be used in regular reactors."

State of play: The Biden administration in November said it wants to triple nuclear energy production by 2050 to meet the country's climate goals and fulfill spiraling electricity demand.

  • Nuclear energy is the single largest source of zero-emissions energy in the U.S., producing about 20% of the country's electricity.

Yes, but: Some 88,000 tons of nuclear waste are sitting in storage across the U.S., with another 2,000 tons added every year.

  • Efforts to recycle the fuel or develop a long-term storage site have collapsed in scandals, which in turn have prompted opposition to building new nuclear plants.

Of note: The most prominent U.S. effort to develop a permanent waste repository, at Yucca Mountain in Nevada, saw costs spiral to $100 billion before congressional opposition all but killed the project.

  • Even if the site were completed, it would be filled to capacity as soon as it opened — and that's not accounting for advanced nuclear energy projects like small modular reactors that are now in development.

💭 Our thought bubble: Particle accelerators and nuclear reactors sound ultra-expensive. But all Transmutex needs to do is convince government policymakers that its approach is cheap, safe, and workable.

Driving the news: Union Square Ventures and Steel Atlas led the company's all-equity round, which closed this month.

  • At One Ventures, HCVC, AlleyCorp, House Of Ventures, Presight Capital, Verve Ventures, FONGIT and Tiny Supercomputer Investment joined.
  • At One partner Helen Lin and Steel Atlas partner Cameron Porter joined Transmutex's board.

What's next: Transmutex has completed a digital twin simulation of its system. It's now in talks with government agencies in Europe and Asia to build the company's first 300 MW site, at an estimated cost of $2 billion to $3 billion.

  • The Geneva-based company plans to raise several hundred million dollars to begin construction in the next three years, Servan-Schreiber says. "Once we find a customer, we plan to do a Series B," he notes.
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