AltaRock Energy Inc., headquartered in Seattle, Washington and having a technology development office in Sausalito, California, is a privately held corporation that focuses on the development of geothermal energy resources and Enhanced Geothermal Systems (EGS). AltaRock has filed patent applications and holds exclusive licenses for related intellectual property related to EGS.  In 2008, it started its first project near The Geysers to demonstrate the ability of EGS to be a reliable, renewable and clean source for the production of electric power.
AltRock’s efforts to expand EGS technologies are supported by a 2006 Massachusetts Institute of Technology (MIT) report  that concluded EGS has the potential to provide 100 GWe (gigawatts of electricity) or more for the U.S. by 2050.
Co-founded in 2007 by Andrew Perlman, Susan Petty, and other business partners, AltaRock has received backing from investors such as Google.org, Advanced Technology Ventures , and Vulcan Capital, as well as demonstration grant funding from the United States Department of Energy (DOE).
The Newberry EGS Demonstration
The company currently has a demonstration project underway about 30 miles south of Bend, Oregon in the Deschutes National Forest. The Newberry EGS Demonstration is located on an existing Federal lease designated for geothermal use and is supported by a committee that includes representatives of the community, environmental groups, government and the geothermal industry. AltaRock’s Newberry EGS Demonstration will create an EGS reservoir in the high-temperature, low-permeability resource present on the northwest flank of the Newberry Volcano. The Demonstration will use hydraulic shearing (as opposed to hydraulic fracturing) and other stimulation techniques to induce and sustain fluid flow and geothermal heat extraction, culminating in the conceptual design of a commercial-scale well field and power plant. Water usage  and induced seismicity  analyses for the demonstration site have been completed and conclude the project poses little risk to the area or local communities.
The Geysers Demonstration
In 2008, AltaRock started a demonstration project at The Geysers geothermal field. The Geysers field has hundreds of megawatts of unused electric power generating capacity due to the lack of steam caused by several decades of reservoir depletion. At The Geysers demonstration, AltaRock intended to re-drill a well originally drilled in 1988 and used for years to inject water to produce steam for the existing geothermal power plants. Three attempts were made to re-drill the well from various depths but the drilling assembly became stuck each time in unstable serpentinite formation. Drilling at The Geysers demonstration site has been suspended  while the company evaluates a number of alternative well locations at the Geysers and elsewhere for demonstrating this technology.
Blue Mountain is a traditional geothermal energy site in the Black Rock Desert of Nevada that opened in 2009 but has since underperformed. AltaRock Energy was originally hired by EIG Global Energy Partners in 2014 to help bring the site up to full capacity with its technology. In May 2015, AltaRock acquired the Blue Mountain site itself in the hopes of using it as a source of revenue while it continues its research into next-generation EGS. In order to bring capacity at the site up to 50 megawatts, the company plans to first use hydroshearing and then possibly drilling. Hydroshearing, a technology developed by AltaRock to improve the performance of existing geothermal wells, involves pumping cold water and other particles into a reservoir in order to block parts of the well and allow small cracks to form. The materials injected then biodegrade, allowing the new cracks to open up. These cracks permit new water to flow that can be used to generated steam and thus energy. The acquisition marks a turning point for the company and the future of geothermal power in the US, as it will test the viability of a business model that relies on raising revenue from upgrading existing geothermal sites in order to finance new enhanced EGS sites in the future. 
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- "Use of multiple stimulations to improve economics of EGS". U.S. DOE. Archived from the original on 7 April 2011. Retrieved 2011-03-19.
- "Newberry Volcano EGS Demonstration". U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE). Archived from the original on 7 April 2011. Retrieved 2011-03-19.
- "Newberry Project". Newberry Geothermal Project. Retrieved 2011-03-19.
- "EVALUATION OF WATER USAGE FOR THE NEWBERRY EGS DEMONSTRATION" (PDF). AltaRock Energy Inc. 2011-02-19. Retrieved 2011-03-19.
- "DEVELOPMENT OF SCENARIO GROUND SHAKING MAPS AND EVALUATIONS OF THE IMPACTS OF GROUND SHAKING ON LOCAL BUILDINGS, AVALANCHES, AND THE LAVA RIVER CAVE" (PDF). AltaRock Energy Inc. 2011-01-31. Retrieved 2011-03-19.
- "AltaRock EGS Demonstration Project Status with NCPA at The Geysers" (PDF). AltaRock Energy Inc. 2009-10-19. Retrieved 2011-03-19.
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- AltaRock Energy Inc. website
- Geothermal Technologies Program - Enhanced Geothermal Systems (U.S. Department of Energy)
- Newberry Enhanced Geothermal Systems Demonstration
- Geothermal Technologies Program (U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE))