Geothermal startup Mazama Energy announced on Thursday that it has raised $135 million in an oversubscribed Series B funding round. This new capital will support the company's efforts to develop horizontal wells in super-hot rocks, with each well designed to generate 15 megawatts of electricity.
Mazama plans to begin generating electricity sometime next year. The company stated that its initial site in Oregon has the potential to produce 10 gigawatts of electricity, an increase from last year's estimate of 5 gigawatts by investor Vinod Khosla.
Enhanced geothermal startups, including Mazama, are targeting deeper and hotter rock formations than previous geothermal projects. Mazama has drilled past 10,000 feet in 15 days, aiming for approximately 15,000 feet deep, where it can access 750˚ F (400˚ C) heat. At these depths, water transforms into a "supercritical" fluid, which Mazama claims allows each well to produce up to 10 times more power than traditional geothermal technologies.
The new funding round was led by Centaurus Capital and Doerr Capital, with participation from ConocoPhillips and Shell Ventures. Existing investors, including Khosla Ventures and Gates Frontier, also returned, alongside new investors SiteGround Capital, H. Barton Asset Management, and the Jeffrey and Marieke Rothschild Foundation. Mazama was incubated at Khosla Ventures.
While work at its Oregon site is in early stages, Mazama has secured land for a second development. The startup aims to complete the first site's development by 2030, at which point it expects to generate 200 megawatts of electricity.