Khosla-backed Mazama Energy just raised $135M to drill deeper into super-hot-rock geothermal

Mazama Energy, a geothermal startup backed by investor Vinod Khosla, recently secured $135 million in a Series B round of funding. The new capital will be utilized to develop horizontal wells in super-hot rocks, capable of generating 15 megawatts of electricity per well. Initially, the company estimated its Oregon site could produce 5 gigawatts, but this figure has since been revised upwards to 10 gigawatts.

Enhanced geothermal startups like Mazama are gaining traction as a potential power source for large loads like AI data centers. These companies focus on drilling deeper and hotter rock, as opposed to traditional geothermal projects. Mazama has managed to drill past 10,000 feet in just 15 days, reaching about 15,000 feet deep. At such extreme depths, temperatures soar to 750°F (400°C), which can be utilized to produce supercritical fluid — a state of matter that allows for more efficient energy absorption than conventional steam.

This technology could potentially yield a massive 63 terawatts of electricity if just 1% of super-hot rock worldwide were tapped. While subsequent developments are still in their infancy, Mazama has already set its sights on another location. The company aims to complete the development of its first site by 2030, generating an estimated 200 megawatts of electricity by that time.

The recent funding round was led by Centaurus Capital and Doerr Capital, with backing from ConocoPhillips, Shell Ventures, and existing investors such as Khosla Ventures and Gates Frontier. Additional investors, including SiteGround Capital, H. Barton Asset Management, and the Jeffrey and Marieke Rothschild Foundation, also joined the funding campaign.