OpenAI Chief Executive Sam Altman said on Monday he has stepped down from the ​board of directors of Helion Energy, the fusion startup he ‌has backed since 2015, as the companies start ​to explore working together “at significant scale”.

Altman, who is ⁠also on the OpenAI board, said the dual roles had become untenable as the ChatGPT maker eyes future partnerships with ‌Helion. In a post on social media platform X, Altman added that he will ‌have a financial interest in Helion and will recuse ‌himself ⁠from any deal negotiations.

“Sam has played ⁠an integral role in Helion’s development… I look forward to working with (Altman) in this new capacity,” Helion CEO David Kirtley said in ​an X post separately.

OpenAI ‌is also in advanced talks to buy electricity from Helion Energy, Axios reported on Monday, citing a person familiar with the situation.

Under the terms being ‌discussed, OpenAI could secure a guaranteed portion of ​Helion’s production, initially 12.5%, with talks centering on OpenAI receiving the equivalent of 5 gigawatts ⁠by 2030, scaling to 50 gigawatts by 2035, the report added.

OpenAI did not immediately respond to Reuters request ‌for comment on the Axios report. A spokesperson for Helion said: “beyond the previously announced deals with Microsoft and Nucor, Helion has not made any new customer announcements.”

A potential deal underscores a broader race among the world’s largest technology companies to lock in ‌long-term energy supplies as the explosive growth of artificial intelligence strains power ​grids.

Microsoft, Google, and Amazon have all struck deals with nuclear and fusion companies that would have ⁠seemed far-fetched just a few years ago.

Helion was ⁠founded in 2013 by Kirtley, along with John Slough, Chris Pihl, and George Votroubek. It ‌has raised over $1 billion in total funding, with a $425 million Series F closed in January 2025 that ​valued the company at $5.4 billion.