Mazama Energy, Inc., has announced a major advancement in clean energy with the creation of the world’s hottest Enhanced Geothermal System (EGS) at its pilot site in Newberry, Oregon.
The system achieved a record bottomhole temperature of 629°F (331°C), setting a new global benchmark for geothermal development. This milestone marks a step toward delivering affordable, carbon-free baseload power at a terawatt scale, with costs targeted below 5 cents per kilowatt-hour (kWh).
Advancing energy for data centers
As global demand for reliable, high-density power grows, especially from data centers and artificial intelligence operations, Mazama’s development offers a dependable and sustainable solution. Unlike solar and wind, which are intermittent, or fossil fuels, which are carbon intensive, high-temperature geothermal energy can deliver continuous, carbon-free electricity from almost any location. This makes Mazama’s geothermal platform well suited for hyperscale data centers and industrial electrification.
“With geothermal, you get global, round-the-clock energy that is carbon-free, cost-stable, and grid-independent,” said Sriram Vasantharajan, CEO of Mazama Energy. “Our team’s accomplishments expand the frontiers of geothermal power into significantly hotter and more heterogeneous rock regimes than ever before. The Newberry pilot provides a blueprint for unlocking baseload, utility-scale, carbon-free energy from the Earth’s crust worldwide, which is what the next generation of AI and cloud infrastructure requires.”
Dr John McLennan, Reservoir Management Lead at Utah FORGE, said, “This is a validation of an integrated development program that has successfully interconnected two slightly deviated wells and circulated a representative working fluid – a fulfillment of a vision from nearly fifty years ago to create a full scale EGS reservoir which was initiated by Los Alamos National Laboratory at Fenton Hill, New Mexico. This proof of concept opens the door to deeper and hotter opportunities at Newberry and beyond.”
Towards terawatt-scale geothermal energy
Following the success of its pilot, Mazama plans to move forward with a 15 MW demonstration project in 2026, followed by a 200 MW development at Newberry. The company also aims to extend drilling into the SuperHot Rock regime, with temperatures above 400°C, using advanced materials, cooling systems, and stimulation methods. This next phase could deliver up to ten times more power density while using 75% less water and requiring 80% fewer wells than current geothermal practices.
Located in Oregon’s Cascade Range, the Newberry site is one of the largest geothermal reservoirs in the United States. Mazama’s engineers completed and stimulated a legacy well as an injector, then drilled a 10,200-foot deviated producer well with precision, aligning within six feet of its intended trajectory. Circulation tests confirmed strong connectivity between the wells and the successful creation of the world’s hottest EGS.
The project demonstrated the use of advanced drilling, high-temperature well construction, and innovative stimulation techniques to operate under extreme geological and thermal conditions. The team worked year-round at a remote, high-altitude site without any lost-time incidents.
During the technical phase, Mazama achieved:
* Peak drilling penetration rates of 100 feet per hour
* Average rates of 76 feet per hour across granite, basalt, and granodiorite
* Bit runs reaching 2,760 feet through volcanic rock
* Zero downhole equipment failures
* Stable well integrity and cement performance at ultra-high temperatures
A key factor in this achievement was Mazama’s proprietary thermal stimulation process, developed specifically for enhanced geothermal environments. By adapting conventional hydraulic fracturing techniques, the process allows for complex fracture creation and improved reservoir connectivity. The Newberry project also demonstrated the use of crosslinked fracturing fluids, sliding sleeves, tracers, and fiber-optic diagnostics for real-time fracture mapping and temperature monitoring.