Quaise Energy has raised US$134mn in the initial close of its Series B financing round as it looks to build what it says will be the world’s first commercial superhot geothermal power plant and advance its millimeter wave drilling technology.
“Our ambition is to power civilisation with Earth’s most compelling energy source,” said Carlos Araque, the company’s CEO and President. “This round takes us from field-proven technology to first commercial revenues.”
The Series B financing brings its total funding raised to date to US$230mn.The proceeds will be used to develop Project Obsidian in Central Oregon and continue advancing the company’s millimeter wave drilling system to depths exceeding five kilometres.
The Houston-based company reported that the latest funding round was led by Prelude Ventures, with strategic investments from JERA Co., Inc. and Idemitsu Kosan, two of Japan's largest energy companies.
Nearly all existing investors, including Safar Partners, also participated, it added.
In a statement, Quaise said additional equity and debt financing is expected to close soon, adding further financial firepower to its commercialisation plans.
The company’s drilling technology, developed at the Massachusetts Institute of Technology, uses millimeter waves to ablate rock at depths and temperatures beyond the reach of conventional drilling methods.
Quaise said the approach could access rock temperatures between 300°C and 500°C, allowing geothermal systems capable of rivaling fossil fuel and nuclear power in energy density while matching renewable energy costs.
The company has drilled more than 100 metres through granite at its Central Texas field site in 2025 and is now approaching one kilometre in depth.
According to the Quaise statement, reaching that milestone would represent the deepest penetration achieved using millimeter wave drilling and the deepest ever recorded by any non-contact drilling technology.
Project Obsidian is currently under construction on federal geothermal leases in Oregon’s Deschutes National Forest.
The company believes the project has gigawatt-scale potential and hopes to deliver electricity to the grid by 2030.
Mark Cupta, Managing Director at Prelude Ventures, which supported the latest fundraiser, said the project demonstrates the company’s progress toward commercial deployment.
“What the team has achieved in the field and what they are now building at Project Obsidian validates that conviction, and we are proud to continue supporting Quaise as they move from proving the technology to powering the grid with clean, reliable energy nearly anywhere on Earth,” he said.