EnergyFirst U.S. commercial enhanced geothermal system connected to the grid

Published 17 April 2013

Enhanced geothermal system (EGS) projects capture power from intensely hot rocks, buried thousands of feet below the surface, which lack the permeability or fluid saturation found in naturally occurring geothermal systems. The Energy Department the other day announced the U.S. first commercial EGS project which supplies electricity to the grid.

Schematic of enhanced geothermal system // Source: commons.wikimedia.org

The Energy Department the other day recognized the U.S. first commercial enhanced geothermal system (EGS) project to supply electricity to the grid. Based in Churchill County, Nevada, Ormat Technologies’ Desert Peak 2 EGS project has increased power output of its nearby operating geothermal field by nearly 38 percent — providing an additional 1.7 megawatts of power to the grid and validating this emerging clean energy technology.

“Developing America’s vast renewable energy resources sustainably is an important part of President Obama’s all-of-the-above energy strategy to create jobs and strengthen U.S. global competitiveness,” said Assistant Secretary for Energy Efficiency and Renewable Energy David Danielson. “The Churchill County geothermal project represents a critical investment to ensure America leads in this growing global industry, helping to create new manufacturing, construction and operation jobs across the country while diversifying our energy portfolio and reducing pollution.”

Enhanced geothermal system projects capture power from intensely hot rocks, buried thousands of feet below the surface, which lack the permeability or fluid saturation found in naturally occurring geothermal systems.

As demonstrated in this infographic, EGS technologies utilize directional drilling and pressurized water to enhance flow paths in the subsurface rock and create new reservoirs, capturing energy from resources that were once considered uneconomical or unrecoverable. With the support of research and development investments from the Energy Department’s renewable energy and oil and gas portfolios, American companies like Ormat Technologies are now taking advantage of this untapped resource. The U.S. Geological Survey estimates that EGS in the United States has the potential to enable development of 100 to 500 gigawatts (GW) of geothermal resource capacity.

Ormat Desert Peak project is using a $5.4 million Energy Department investment — matched by $2.6 million in private sector funding — to extend the life of previously unproductive geothermal wells. Since the project’s start in 2008, the Energy Department has worked with Ormat, GeothermEx, the U.S. Geological Survey, and Lawrence Berkeley and Sandia National Laboratories to develop cost-effective production technologies that utilize protective environmental best practices and monitoring.

The Desert Peak project follows two other Energy Department-supported projects focused on demonstrating the commercial viability of EGS:  The Calpine demonstration project at The Geysers in Middletown, California and the AltaRock demonstration project at the Newberry Volcano near Bend, Oregon.

DOE says that these projects have realized important achievements in the department’s near- to long-term EGS strategy to develop resources ranging from existing fields to undeveloped or greenfield sites.