Mazama Energy raises $135M for superhot geothermal at Oregon volcano

A startup called Mazama Energy just raised $135 million to develop a new kind of geothermal power near Oregon's Newberry Volcano. The company drills wells into extremely hot rock deep underground to generate electricity, an approach known as enhanced geothermal, which fractures dry rock rather than relying on natural hot-water pockets the way older geothermal plants do. Last year Mazama said it built the hottest such well in the world, reaching 629 degrees Fahrenheit. The idea is that hotter rock means fewer, more efficient wells and cheaper power overall.

The new funding round was led by investors including Centaurus Capital and Doerr Capital, with oil companies ConocoPhillips and Shell Ventures also putting money in. Mazama plans to use the cash for a project called Ceres, backed by the U.S. Department of Energy, which will test horizontal drilling designed to get 15 megawatts of power from a single well. Drilling is expected to start later this year, with testing in early 2027.

This is not a program homeowners can sign up for or a technology available for houses. It is early-stage research into a power source that, if it works at scale, could eventually add more clean, round-the-clock electricity to the grid in parts of the western United States. Other companies, including Fervo Energy and Quaise Energy, are pursuing similar projects, showing more investor interest in this kind of geothermal power right now.