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EnvironmentSam Altman

Sam Altman just took a nuclear energy startup public for $500 million. Its CEO wants to provide ‘energy at planetary scales for a billion-plus years’

Paolo Confino
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Paolo Confino
Paolo Confino
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July 11, 2023, 2:31 PM ET
OpenAI founder and CEO Sam Altman holding two paper cups.
The Sam Altman-backed nuclear energy startup Oklo announced it will go public Tuesday. Drew Angerer—Getty Images

OpenAI founder Sam Altman just took another step toward his vision of a future powered by A.I. and widely affordable clean energy, with the announcement that Oklo, a startup specializing in “nuclear microreactors” of which he is chairman, will go public. 

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Oklo announced Tuesday that it will go public in 2024 via SPAC with AltC. Acquisition Corp, a company cofounded by Altman and Michael Klein, former CEO of Global Banking at Citigroup. Oklo is attempting to replicate the process of nuclear fission that occurs in nuclear power plants, with much smaller reactors. 

The company was founded in 2013 by Caroline Cochran, currently Oklo’s chief operating officer, and Jacob DeWitte, its CEO. Altman became involved in 2013 when he met DeWitte and Cochran, who would eventually join Y Combinator, the famed startup accelerator of which Altman was president at the time, according to CNBC.

So far, the company has raised around $50 million, DeWitte told Fortune in a phone interview Tuesday. Data from deal-tracking website Pitchbook shows Oklo also received roughly $420,000 in grant money from the U.S. Department of Energy. The public offering is set to bring in an additional $500 million, which Oklo says it plans to use to build its first microreactor. 

“Being public is going help us attract the right kind of financing, and at a larger scale given the similarities of what’s been done in other power generation technologies with similar [power sales] models,” DeWitte says, referencing the business models of emerging renewable energy companies after which Oklo is modeling itself.

Oklo envisions that its microreactor technology would be housed inside of smaller power plants, that according to renderings on its website look something like Northern European mountain lodges, which would generate nuclear power without creating nuclear waste. If their hypothesis proves out, it would allow for these smaller nuclear reactors to operate without constant human supervision, a critical component since Oklo’s power plants are designed to be built in remote locations. 

DeWitte went on to explain that Oklo sees two promising opportunities for potential future customers: The first is in facilities like data centers or military bases that are looking to expand their power capacity but don’t have ready access to an existing power grid; and the second is as a new solution to help companies meet their decarbonization goals.

In a promotional video, Dewitte offers a glimpse into the company’s ambitions. “Building one [plant] is relatively easy, the fun part is thinking about how you build hundreds or thousands,” he says. 

Oklo has already secured a permit from the Department of Energy to built its first microreactor at the the Idaho National Laboratory, the nation’s leading center for nuclear research, which the company expects to be active by 2026 or 2027. It will also provide Oklo with used nuclear fuel to power its microreactor. 

Sam Altman has long been interested in energy

Altman’s vision of the future relies on developments in two main fields of technology: A.I. and energy. In addition to Oklo, Altman also invested $375 million—his largest ever personal investment—in nuclear energy company Helion. Microsoft recently agreed to purchase energy from Helion starting in 2028. (Microsoft invested a reported $13 billion in Altman’s OpenAI). 

The multiple investments in nuclear energy are likely an effort to cover the full breadth of cutting-edge nuclear energy research. Helion researches nuclear fusion—the combining of unstable atoms to create energy—while Oklo works on nuclear fission that splits atoms to release energy. 

However, nuclear fusion is still in its infancy. In December 2022 scientists in the Department of Energy reached a milestone when they were able to create a nuclear fusion reaction that created more energy than had been input, yielding a net gain. 

Nuclear evangelists believe that both will be necessary to create sufficient amounts of clean energy to meet the world’s needs as it weans itself off fossil fuels. In an interview with CNBC, Altman referred to lowering the cost of energy as one of the key enablers of a brighter future for humanity. Altman’s vision of a far-reaching utopia, enabled by technology has been reported extensively, especially since ChatGPT vaulted itself into the public consciousness when it was released in November. In an April interview with Insider he opined that “I think we can have a much, much better world.” 

DeWitte and Oklo seem to welcome Altman’s extremely long-term perspective regarding nuclear power. “That kind of thinking is what’s really important to provide clarity on what problems to focus on,” he says.

However, DeWitte acknowledges that the day-to-day goings-on of running a company keep him grounded on practical things like getting plants built or, say, planning for the announcement that the company will go public. Although, it appears Altman’s enthusiasm has rubbed off on DeWitte, who says that if things pan out for Oklo, the company would be able to provide “energy at planetary scales for a billion plus years.”

[This article has been updated to include comments from an interview with Oklo CEO Jacob DeWitte. 

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About the Author
Paolo Confino
By Paolo ConfinoReporter

Paolo Confino is a former reporter on Fortune’s global news desk where he covers each day’s most important stories.

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