Helion Energy, a US-based start-up focused on generating zero-carbon electricity from fusion, has raised $500m in a Series E funding round.
The funding round was led by OpenAI CEO and former Y Combinator president Sam Altman.
Helion’s existing investors, including Dustin Moskovitz, Mithril Capital and Capricorn Investment Group, also participated in the funding round.
The company will use the proceeds to complete the construction of its seventh-generation fusion generator, Polaris.
Helion said that the generator builds on the performance of its six predecessors and is powered by the company’s pulsed non-ignition fusion technology.
Polaris is expected to reach net electricity production in 2024, a capability that may facilitate the development of fusion power plants in the future.
Helion broke ground in Everett, Washington, earlier this year to build Polaris.
Helion Energy founder and CEO Dr David Kirtley said: “This funding ensures that Helion will be the first organisation to generate electricity from fusion.
“Our sixth prototype demonstrated that we can reach this pivotal milestone.
“In just a few years, we will show that the world can count on fusion to be the zero-carbon energy source that we desperately need.”
Sam Altman said: “With a tiny fraction of the money spent on other fusion efforts, and the culture of a startup, this team has a clear path to net electricity.
“If Helion is successful, we can avert climate disaster and provide a much better quality of life for people.”
Under the terms of the funding round, Helion can secure a further investment of $1.7bn if it achieves key performance milestones.
In June, the company became the first private fusion company to heat a fusion plasma to 100 million degrees Celsius, which it described as a ‘critical’ engineering milestone for generating energy from fusion.