Quaise Energy finalized a $180 million Series B round to advance its millimeter-wave drilling technology and construct Project Obsidian, the first commercial superhot geothermal plant in Oregon.
Quaise Energy closed its $180 million Series B equity financing, bringing the company’s total capital raised to $280 million. This final close followed an initial Series B tranche of $134 million announced in July 2026. The round funds commercialization of the company’s millimeter-wave (gyrotron based) drilling technology and advancement of Project Obsidian, positioned as the world’s first commercial superhot geothermal power plant.
The Series B totaled $180 million in equity. Nabors Industries (NYSE: NBR), a major land drilling contractor and existing partner, contributed $35 million and emerged as Quaise’s largest shareholder with approximately 14% fully diluted ownership. Nabors funded its stake primarily through the issuance of roughly 392,000 shares of its common stock.
The July first close was led by Prelude Ventures, with strategic participation from JERA Co., Inc. and Idemitsu Kosan (two of Japan’s largest energy companies). Nearly all existing investors, including Safar Partners, returned. Additional named participants in the full round include Idemitsu Americas Holdings. Advisors to Quaise included BofA Securities and Goldman Sachs.
Alongside the equity investment, Quaise and Nabors executed a strategic framework agreement covering drilling operations, technology integration, and commercial development. Key elements include exclusivity for Nabors to provide drilling services on Quaise projects, access to a dedicated Nabors land rig (a PACE®-B unit is already active at Project Obsidian), and collaboration on reservoir modeling, well design, drilling strategy, rig engineering, automation, and potential global expansion. This deepens a multi year partnership that previously produced the industry’s first hybrid conventional plus millimeter wave drilling rig.
How will Quaise Energy use the funds?
Proceeds primarily support two interconnected priorities:
- Development and construction of Project Obsidian.
- Acceleration of the millimeter-wave drilling system toward commercial depths exceeding 5 km (with longer term targets of 10–20 km to reach 300–500°C rock nearly anywhere).
The company is simultaneously pursuing project level equity and debt financing, with expectations of further announcements. Earlier commentary indicated plans to secure additional capital (including grants and debt) specifically for Obsidian beyond the corporate Series B.
Project Obsidian Details
Project Obsidian is located on federal geothermal leases in Central Oregon (Deschutes National Forest area, south of Newberry Volcano / adjacent to Newberry National Volcanic Monument). The site benefits from exceptionally high geothermal gradients (approximately 100°C/km), allowing superhot temperatures at relatively shallower depths than many other locations.
- Phased capacity: Initial phase targets 50 MW of firm, zero carbon baseload power; expansion to 250 MW total (adding ~200 MW from deeper, hotter reservoirs); longer term potential of 1 GW+ at the site. Surface footprint for the initial well systems is compact (on the order of 20 acres for key facilities).
- Resource targets: Two fractured reservoirs in Phase 1, one averaging ~315°C (peak ~365°C) and another averaging ~365°C (peak ~415°C), using enhanced geothermal system (EGS) configurations (typically injector-producer triplets). Later phases will push hotter (up to ~450°C / 850°F range) using millimeter-wave drilling.
- Timeline: Confirmation well and early EGS drilling/flow testing targeted for 2026; commercial operation aimed for 2030; further expansion in the early 2030s. A Nabors rig is already on site.
- Commercial offtake: An undisclosed hyperscaler (data center focused) customer has contracted for the first 50 MW. Additional offtake discussions for the remaining capacity are underway, capitalizing on demand for 24/7 carbon free power.
Quaise describes the project as a catalyst for global scaling, demonstrating that superhot rock (300–500°C) can deliver 10–100× the power density of conventional geothermal per well, enabling reuse of existing fossil fuel infrastructure, lower land/material intensity, and deployment far beyond traditional hydrothermal or Ring of Fire settings.
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Quaise’s core innovation is a hybrid drilling platform: conventional rotary drilling reaches basement rock, after which high power millimeter waves generated by a surface gyrotron are transmitted downhole via waveguide tubing. The energy ablates (vaporizes) rock without mechanical contact or complex downhole tools that fail at extreme temperatures. Purge gas returns the vaporized material. The approach builds on more than a decade of MIT Plasma Science and Fusion Center research and aims to unlock ubiquitous, high enthalpy resources that conventional or other enhanced geothermal systems cannot economically access. Field progress includes hybrid rig demonstrations and granite drilling exceeding 100 meters in 2025, with 1 km targets in 2026 and multi kilometer commercial depths thereafter.
The $180 million close and Nabors partnership represent a material de-risking step for superhot geothermal. It pairs venture and strategic capital (including major Asian energy companies) with an established oilfield services platform that brings rigs, operational expertise, global reach, and a ready workforce transferable from oil and gas. Success at Obsidian would validate a pathway to terawatt scale, always-on, zero fuel, zero waste electricity with high capacity factors and minimal surface impact, positioning geothermal as a potential backbone resource competitive with or superior to fossil and nuclear options in density and dispatchability.
Risks inherent to the sector and technology remain, including subsurface uncertainty, drilling performance at scale, reservoir stimulation and longevity at extreme temperatures, regulatory timelines on federal lands, and the capital intensity of first of a kind plants. The staged development approach (start with more accessible superhot temperatures using conventional methods, then introduce millimeter wave systems) and concurrent project financing are designed to mitigate these. Total funding of $280 million provides runway through key 2026–2027 milestones, after which a Series C is anticipated.
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