Twilio co-founder’s fusion power startup raises $450M from Bessemer and Alphabet’s GV

Inertia Enterprises has successfully raised $450 million to develop one of the most powerful lasers in the world, laying the groundwork for a grid-scale fusion power plant set to begin construction in 2030. This ambitious initiative builds upon advanced technology from the National Ignition Facility at Lawrence Livermore National Laboratory, known for achieving controlled fusion reactions that generate more energy than they consume. Led by Bessemer Venture Partners, the Series A funding round saw participation from notable investors including GV, Modern Capital, and Threshold Ventures. Among Inertia’s co-founders are Jeff Lawson, a Twilio co-founder and former CEO, Annie Kircher, who spearheaded successful experiments at NIF, and Mike Dunne, a Stanford professor instrumental in designing a fusion power plant based on NIF’s innovations. Kircher continues her role at Lawrence Livermore while contributing to Inertia's mission. The path to operational fusion power is still fraught with challenges, as Inertia aims to create a laser system capable of delivering 10 kilojoules ten times per second. Their approach centers on inertial confinement fusion, where lasers compress fuel targets to induce atomic fusion and release energy. This method draws from NIF’s designs, utilizing laser light converted into X-rays to heat and compress the fuel pellets. Inertia's design will employ 1,000 lasers targeting 4.5 mm fuel pellets, each costing less than $1 to mass produce. This contrasts sharply with NIF’s system, which relies on 192 lasers and meticulously crafted targets that can take days to produce. By adopting similar foundational principles as NIF but with a commercial focus, Inertia aims to drastically reduce costs. This funding announcement is part of a larger trend in the fusion energy sector, which has seen over $10 billion in investments in recent months. Numerous startups have emerged, with at least a dozen raising more than $100 million each. For instance, Avalanche recently announced a $29 million funding round for its compact fusion reactor, while Type One Energy reported an $87 million investment earlier this year. Major players like Commonwealth Fusion Systems have also raised significant funds, including an impressive $863 million from a diverse group of investors. In a notable shift, two fusion companies have opted for public listings through reverse mergers. General Fusion announced its merger with Spring Valley III, valuing the combined entity at $1 billion, while TAE Technologies revealed plans to merge with Donald Trump’s social media firm, projecting a combined valuation of $6 billion. These developments highlight a rapidly evolving landscape in the fusion energy sector, underscoring the growing interest and investment in this promising field.