Former SpaceX Engineer Raises $22M to Build Geothermal Power Plants Using Rocket Engine Technology

Geothermal Energy is increasingly gaining attention as one of the world’s most promising clean power sources. According to the International Energy Agency (IEA), global geothermal resources could provide at least 42 terawatts of capacity—more than twice the amount of Energy the world consumed last year.

Despite its enormous potential, investment in geothermal technology still trails far behind funding flowing into advanced nuclear fission and fusion startups.

Against that backdrop, geothermal startup Critical Energy has raised $22 million in early funding, including $19 million in seed financing and an additional $3 million in venture debt, to accelerate development of modular turbines designed specifically for geothermal power plants. The company said the funding will be used to build its first 2.5-megawatt geothermal project.

While many nuclear energy startups are targeting commercial deployment in the early 2030s, Critical Energy believes geothermal power could reach large-scale deployment much sooner.

“Geothermal is going to beat them to it. By a lot,” said Spencer Jackson, co-founder and CEO of Critical Energy. “In four or five years, I hope that we’re doing many gigawatts a year.”

Growing electricity demand, particularly from AI infrastructure and data centres, is increasing interest in geothermal Energy. A recent report suggested advanced geothermal systems could supply nearly two-thirds of new data centres by 2030.

Jackson believes one of the industry’s biggest obstacles is the shortage of suitable turbines. Many geothermal projects currently rely on large conventional turbines that require lengthy on-site assembly. Critical Energy instead plans to manufacture modular turbine systems in factories, allowing faster deployment and lower costs.

To develop the technology, Jackson has drawn on his experience working at SpaceX, where he contributed to projects including Falcon Heavy, Starship, and the Raptor rocket engine. Many of the turbine components resemble rocket engine turbomachinery, with manufacturing currently handled by specialist machine shops, while other parts are sourced commercially. Over time, the company may bring additional production in-house, following a strategy similar to Tesla and SpaceX.

Critical Energy expects its first commercial installation to be completed by 2027 at an existing geothermal site similar to Iceland’s facilities or California’s Geysers geothermal field. The company is also developing a larger five-megawatt turbine module designed for enhanced geothermal developers such as Fervo Energy, which drill deeper underground to access additional heat resources.

Looking further ahead, Jackson said the company’s long-term goal is to manufacture gigawatts of geothermal turbine capacity annually. “We are looking for the fastest path to gigawatts of scalable power on the grid,” he said. “Long-term goal is 300 gigawatts a year in 2045.”

Jackson also expects traditional oil and gas companies to play a significant role in expanding geothermal Energy because of their expertise in large-scale drilling operations.

“Geothermal is great because the oil and gas industry has the replicability to do hundreds and then thousands of wells,” he said. “They’re very, very good at drilling wells. But they need turbines, and there’s going to be a massive shortage of those.”

The seed funding round was led by Susa Ventures and Upfront Ventures, with participation from MaC Venture Capital, Susquehanna Sustainable Investments, Humba Ventures, Scribble Ventures, and Underground Ventures. Together with the $3 million venture debt provided by Silicon Valley Bank, Critical Energy’s total early funding now stands at $22 million.