Quaise Energy has announced the first closing of its $134 million Series B round, earmarked to finance Project Obsidian, the world’s first commercial superhot rock geothermal power plant. The facility will be built in central Oregon. Additional equity and debt financing are expected to close shortly, bringing the company’s total raised capital to $230 million.
The round was led by Prelude Ventures, with strategic participation from JERA and Idemitsu, two of Japan’s largest energy conglomerates. Nearly all existing investors, including Safar Partners, rolled over their positions — a clear signal that confidence in Quaise’s technological model has not wavered after early field tests, but has in fact deepened. Project-level equity and debt financing will be announced separately, with commercial offtake partners already identified but not yet disclosed. The goal is to deliver first electrons to the grid by 2030, helping stabilize the Pacific Northwest grid at a time when the region faces surging demand and constrained transmission capacity.
At the heart of the entire operation is the millimeter-wave drilling system, developed over more than a decade of research at the Massachusetts Institute of Technology. The system uses a gyrotron — a device that generates high-frequency waves in the spectrum between microwave and infrared — to ablate rock without any mechanical components in the borehole. The waves are directed downward through a metallic waveguide, melting and vaporizing granite and basalt into fine ash. Unlike a conventional drill bit, which wears out rapidly in hard rock and requires costly trips to the surface for replacement, Quaise’s system has no moving parts downhole. Drilling speeds achieved in public demonstrations have reached five meters per hour through granite, compared to fractions of a meter per hour with traditional systems. The approach is hybrid: conventional mechanical drilling through shallow sedimentary layers, followed by millimeter waves into the deep rock basement.
Field results are tangible. In 2025, at a test site in Central Texas, Quaise drilled more than 100 meters through granite — the first time the technology penetrated basement rock at full scale under real operational conditions. The system is now approaching one kilometer of depth at the same site, a milestone that would set an absolute record for millimeter-wave drilling and the deepest ever recorded by any contactless drilling technology. The target temperature range is between 300 and 500 degrees Celsius, achievable at many locations around the world. At those temperatures and depths, a geothermal plant can produce energy comparable to today’s most efficient gas or nuclear facilities.
Series B proceeds will also fund the advancement of the drilling system toward depths exceeding five kilometers — a necessary step to make superhot geothermal a truly universal energy source. The Project Obsidian site is among the most geothermally studied locations in the United States and holds gigawatt-scale potential. If timelines hold, by the end of the decade Quaise could demonstrate that deep geothermal is capable of delivering clean baseload power at industrial scale, paving the way for the model to be replicated in markets around the world.
