Inertia Raises $450 Million to Commercialize the Only Proven Fusion Science

Inertia, the commercial fusion energy company, led by Jeff Lawson, Annie Kritcher, and Mike Dunne, has raised $450 million in investment to bring limitless clean energy to the world. The Series A round was led by Bessemer Venture Partners, with participation from additional firms including GV (Google Ventures), Modern Capital, Threshold Ventures, and more.

Founded in 2024, Inertia is developing a fusion pilot plant using physics proven at LLNL’s National Ignition Facility. Funding supports Thunderwall, the world’s most powerful laser, and scalable fuel target production, laying the groundwork for grid-scale energy.

With investor backing and a dedicated team, Inertia aims to deliver the only fusion approach proven to generate more power than it consumes.

“Inertia is building on decades of proven science,” said Jeff Lawson, co-founder and CEO. “The goal is to deliver the world’s highest-power laser, the first fusion target assembly plant, and the first gigawatt-scale fusion power plant, with the team and partnerships in place to achieve this within the next decade.”

Building the first fusion power plant for grid-scale energy demands requires both technical expertise and capital. The Inertia team brings decades of experience in developing and operating the tools behind the only fusion system to achieve ignition.

Co-founder Dr. Annie Kritcher has over 20 years at LLNL and has led fusion experiments at the National Ignition Facility since 2017. She developed the “Hybrid-E” inertial confinement fusion design, including hohlraum, capsule, and laser specifications, which enabled the first controlled experiment to achieve net target energy gain in December 2022. Through a unique agreement, she co-founded Inertia as Chief Scientist while continuing at LLNL, applying her expertise to advance inertial fusion energy toward the grid.

“In three years, fusion has moved from the first net-energy gain to repeated higher-gain results,” said Kritcher. “The focus is now on turning proven physics into commercial-scale fusion energy for people and the planet.”

Inertia’s CTO, Prof. Mike Dunne, brings decades of experience directing large-scale research facilities, including SLAC’s Linac Coherent Light Source, LLNL’s fusion power plant program, and the UK’s Central Laser Facility. His expertise supports the on-time delivery of Inertia’s fusion power plant.

“For the first time, fusion commercialization benefits from three aligned elements: proven physics, public-sector partnerships, and private investment at scale,” said Dunne. “Our role is to leverage these to deliver fusion energy at grid scale.”

At the heart of Inertia’s plan is Thunderwall, the world’s first grid-scale fusion laser. Delivering 10 kJ pulses 10 times per second at 10% efficiency, 50× the power of any prior laser, and paired with mass-produced targets and rapid delivery, it enables a commercially viable, grid-scale fusion power plant.

“Inertia is our first direct fusion investment, thanks to its clear path to commercial energy,” said Byron Deeter, partner at Bessemer. “With top-tier physics and company-building expertise, they’re uniquely positioned to deliver safe, clean, abundant energy.”