Quaise Raises $134 Million to Build First Superhot Geothermal Plant

Quaise Energy has raised $134 million in the first close of a Series B round to fund Project Obsidian, which it describes as the world's first commercial superhot geothermal power plant, lifting the company's total funding to date to $230 million. The round was led by Prelude Ventures with strategic backing from JERA and Idemitsu, two of Japan's largest energy companies, and comes as Quaise's drilling technology approaches one kilometre of depth at a test site in Central Texas. Additional project-level equity and debt financing is expected to close imminently alongside the equity raise.

 

The Drilling Technology Behind the Bet

 

Quaise's core innovation is a millimeter wave drilling system, developed at MIT, that ablates rock using electromagnetic waves rather than the mechanical bits conventional drilling relies on. That distinction matters because conventional drills wear out and lose efficiency at the extreme depths and temperatures needed to reach superhot rock, which is precisely why that heat has remained economically inaccessible in most locations despite being present almost everywhere on Earth. Quaise says the technology can reach rock temperatures of 300 to 500 degrees Celsius in most places worldwide, heat hot enough to generate power at a density the company argues can rival fossil fuel and nuclear plants while matching the cost profile of renewables.

The company points to a specific field validation to support that claim. In 2025, its Texas test site penetrated more than 100 metres through granite, marking the first time the technology reached basement rock at full scale under field conditions rather than in a laboratory. The site is now approaching one kilometre of depth, which would represent the deepest penetration ever achieved by millimeter wave drilling and by any non-contact drilling technology of any kind. That progression from proving the concept in granite to approaching kilometre-scale depth is what the company and its investors treat as evidence the technology is ready to move from research to commercial deployment.

 

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Why Project Obsidian's Location Matters

 

The funding is directed at Project Obsidian, sited on federal geothermal leases in Oregon's Deschutes National Forest, an area the company describes as one of the most studied geothermal locations in the United States. Construction is already underway, with the project targeting gigawatt-scale potential and first electricity delivered to the grid by 2030.

The location carries strategic weight beyond its geothermal characteristics. The Pacific Northwest faces rising electricity demand alongside constrained transmission capacity, a combination increasingly common as data centre growth and broader electrification strain regional grids faster than new transmission lines can be built. Geothermal power offers something variable renewables cannot: continuous, baseload generation that runs regardless of weather, which is why the project is framed specifically around supporting grid stability in a region under growing strain rather than simply adding clean capacity.

 

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Why Japanese Energy Majors Are Buying In

 

The involvement of JERA and Idemitsu signals interest from utilities thinking beyond their own domestic markets. JERA's head of ventures, Takeshi Kodama, described millimeter wave drilling as having the potential to make geothermal a truly global baseload resource, language that reflects the core promise of Quaise's approach: unlike conventional geothermal, which is geographically limited to regions with naturally accessible hot rock, reaching superhot temperatures at depth could make geothermal viable in far more locations worldwide. Idemitsu's Kei Honda framed the investment as part of the company's push into next-generation energy solutions capable of contributing to stable, sustainable power supply at scale.

The Series B is explicitly structured as only the first component of a larger financing package. Project-level equity and debt are being raised in parallel as Quaise moves toward securing first revenue from commercial off-take partners it has not yet named. Whether the drilling system continues to perform as it pushes toward and beyond one kilometre, whether the remaining project financing closes as expected, and whether Project Obsidian delivers power to the Pacific Northwest grid on its 2030 target will determine whether Quaise's superhot geothermal approach becomes the global baseload resource its backers are betting on or remains an ambitious technology still proving itself at scale.

 

Source: Quaise Energy