Still, these reservoirs can be tricky to pinpoint. They're also expensive to reach. A geothermal well can cost $5 million or more. The result: The U.S. currently derives less than 0.5% of its electricity from geothermal.
Some say the key to harnessing this energy source on a massive scale lies with a technology known as enhanced geothermal systems, or EGS for short. The idea is to engineer the necessary conditions by pumping water into the Earth's crust and fracturing the hot rocks below. Heat from the Earth warms the water, whose resulting steam is channeled back to the surface, powering turbines to create electricity. The water is then pumped back underground.
Though still in its infancy, EGS has the potential to open up much of the planet to geothermal development. Tiny plants are already online in France and Germany. More than 30 EGS firms are engaged in exploration and development in Australia.
Google.org, the philanthropic arm of the Mountain View, Calif.-based search engine company, is trying to push EGS in the U.S. It recently gave $10 million to Southern Methodist University's Geothermal Lab to update the nation's geothermal resources map, as well as to two California companies -- Potter Drilling and AltaRock Energy Inc. -- that are working on EGS technologies.
Google is urging the U.S. government to spend big on geothermal R&D as part of the company's push to encourage utility-scale renewable energy that's cheaper than coal. About half the United States' electricity is generated by that dirty fossil fuel. China, already the world's largest emitter of carbon dioxide, is adding coal-fired plants at a swift rate.
EGS "is indeed the sleeping giant of renewable energy," Dan Reicher, director for climate change and energy initiatives at Google.org, said during a recent industry conference in Reno. "It's the killer ap."
Some industry veterans such as Shevenell are miffed that EGS has grabbed the spotlight when there's plenty of energy to be extracted quickly using conventional techniques. Still, she credits Google for helping pump life into a dormant sector.
"This country is in an energy crisis," she said. "We need energy now, and this is a proven way to get it."
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marla.dickerson@latimes.com
