Quaise Energy announced on August 27 the final closing of a $180 million Series B round, including a $35 million investment from Nabors Industries, to finance the Obsidian Project in Oregon where a microwave gyrotron will be used to create wells in rock at 300 °C to 500 °C for what the company aims to be the world’s first commercial superhot geothermal plant. The Series B brings Quaise’s total funding to $280 million; an earlier tranche of $134 million was announced on July 7 and was led by Prelude Ventures with participation from JERA and Idemitsu Kosan.
Nabors contributed $35 million and signed a strategic agreement to provide a dedicated land rig and to integrate its reservoir modelling platform, well design and drilling strategy into the project, combining a conventional shallow rig with gyrotron technology for the hotter basement rock.
How superhot geothermal drilling works
The project relies on a gyrotron — a millimetre-wave generator developed to heat plasma in nuclear fusion reactors — to send a high-frequency microwave beam down a waveguide to the bottom of a well. According to MIT News, engineer Paul Woskov spent 14 years testing the concept of directing this beam downward. In practice, the beam heats, melts and vaporises rock without mechanical contact, a process Quaise calls rock ablation with zero contact. That contactless approach is intended to avoid the limitations of conventional drill bits, which struggle as rock becomes hotter and harder with depth.
Quaise reports it has drilled over 100 metres of granite at a test site in Central Texas and is now approaching 1 kilometre in depth at that location, which the company describes as the deepest achievement of contactless drilling to date. The company acknowledges the technical leap required to move from those tests to wells deeper than 5 km in Oregon and says it must still demonstrate beam stability and efficiency at those greater depths and temperatures.
Obsidian Project, site and timeline
The Oregon lease for the Obsidian Project covers 1,334 acres in the Deschutes National Forest, south of the Newberry volcano and adjacent to the Newberry National Volcanic Monument. The area features an unusually high geothermal gradient of about 100 °C per kilometre, meaning temperatures that would typically require 10 km of drilling elsewhere are present at shallower depths. Quaise describes Phase I target reservoirs at about 315 °C and 365 °C.
Quaise’s published plan calls for two sets of wells — each with one injector and two producers — and two generating units placed side by side. Phase I is designed to deliver 50 MW with power expected on the grid by 2030; Phase II aims for 250 MW, and the company discusses gigawatt-scale deployment in the long term. For the initial wells, conventional drilling will be used through the surface layer; the gyrotron will be deployed when crews reach the hotter basement rock at around 365 °C.
The company and its partners point to potential applicability beyond volcanic areas: Nabors operates drilling rigs in multiple markets, and the combination of a conventional rig for the shallow section with gyrotron ablation for the deep, hot section could be used in sedimentary basins with favourable gradients, the source notes. The statement from Nabors’ president and CEO, Anthony Petrello, described millimetre-wave technology as changing the equation by allowing access to superhot rocks at depths beyond the reach of conventional methods. Quaise CEO Carlos Araque framed the effort as unlocking a powerful clean energy source.
A historical comparison highlights the challenge ahead: the Soviet Kola Superdeep Borehole, started in 1970, reached 12,262 metres by 1989 with a 23-centimetre diameter. Progress stopped not because of the rock itself but because bottom-hole temperatures exceeded 180 °C, making rock behave plastically; the project was abandoned in 1994 for lack of funds and drill bits capable of withstanding the conditions. Quaise acknowledges that it seeks to reach rock three times hotter than Kola’s conditions and must prove the technology at scale beyond its Texas tests.
