https://techcrunch.com/2021/11/05/helion-series-e/

Helion Energy, a clean energy company committed to creating a new era of plentiful, zero-carbon electricity from fusion, today announced the close of its $0.5 billion Series E, with an additional $1.7 billion of commitments tied to specific milestones.

The round was led by Sam Altman, CEO of OpenAI and former president of Y Combinator. Existing investors, including co-founder of Facebook Dustin Moskovitz, Peter Thiel’s Mithril Capital and notable sustainable tech investor Capricorn Investment Group also participated in the round. The funding includes commitments of an additional $1.7 billion dollars tied to Helion reaching key performance milestones. Round-leader Altman has been involved in the company as an investor and chairman since 2015.