US-based fusion energy company Helion has raised $425m in a Series F investment round to advance the commercialisation of its fusion energy technology.
Existing investors including Sam Altman, Mithril Capital, Capricorn Investment Group, Dustin Moskovitz through Good Ventures Foundation, and Nucor participated in the Series F round.
Additionally, new investors Lightspeed Venture Partners, SoftBank Vision Fund 2, and a major university endowment, participated in the oversubscribed and upsized funding round.
The latest funding round brings the total investment in Helion to more than $1bn and values the company at $5.425bn post-money.
Lightspeed Venture Partners managing partner and co-founder Ravi Mhatre said: “Fusion has the potential to be a truly transformational technology for industry and society and we see Helion as leading the race to bring that technology to market.
“After extensive due diligence, we’re very confident in Helion’s technology and leadership as the company moves from research and development into commercial production.”
Helion recently started operating its seventh-generation prototype, dubbed Polaris, which is anticipated to show the first electricity produced from fusion.
Its previous prototype Trenta was the first private initiative to achieve 100 million degrees Celsius, the operating temperature for a commercial fusion power plant.
Helion plans to establish its first fusion power plant in Washington state.
In 2023, the company announced a power purchase agreement with Microsoft to deliver electricity from a 50MW fusion plant starting in 2028.
In addition, Helion has signed a customer agreement with the US-based steel manufacturer and recycler Nucor to develop a 500MW power plant in the 2030s.
Helion co-founder and CEO David Kirtley said: “We are on the brink of delivering a transformative energy solution that can meet the world’s increasing electricity demands while preserving U.S. energy leadership.
“Our mission has always been focused on rapidly developing and deploying safe, reliable fusion generators that provide abundant, affordable electricity.
“Earning the support of such a prestigious group of investors is a testament to our progress in both solving hard scientific and technical challenges and tackling the practical realities of building hardware to commercialise a brand-new technology.”
