Here’s an informative Scientific American article, featuring Google and its investment in Geothermal Technology. – Ilene
Drilling for Hot Rocks: Google Sinks Cash into Advanced Geothermal Technology
More than 2,000 times the entire annual energy consumption of the U.S. is available deep underground
By David Biello
"For $1 billion over the next 40 years, the U.S. could develop 100 gigawatts (a gigawatt equals one billion watts) of electricity generation that emits no air pollution and pumps out power to the grid even more reliably than coal-fired power plants, according to scientists at the Massachusetts Institute of Technology. Now Google.org—the charitable wing of the search engine giant—has chipped in nearly $11 million for this renewable resource: so-called geothermal power, or tapping the Earth’s heat to make electricity.
That makes Google.org the largest funder of enhanced geothermal research in the country, outspending the U.S. government. The Australian government has pledged $43.5 million for such projects and already has several in the works, as do Europe and Japan.
But no such advanced geothermal plants are online in the U.S. at present, and may not be for many years to come. No one has successfully completed all the steps—or demonstrated all the technologies—needed to drill deep beneath the surface, fracture the rock, pump water or other fluids down into the ground to absorb the interior heat, and then bring it to the surface. Once topside, the hot water can be used to make steam to turn turbines and produce electricity.
"We think we can open up fractures, that’s not a problem. You can certainly drill wells and directionally. You can convert the hot water into steam," says chemical engineer Jefferson Tester of M.I.T., who co-authored a report detailing the promise of so-called enhanced geothermal systems (EGS). "It gets down to good well connectivity."
"The fireball that sits within the Earth is a resource," said geothermal evangelist Ólafur Ragnar Grímsson, president of Iceland, a country now largely heated and powered by the Earth’s heat, at the Geothermal Development and Finance Workshop on July 23 in New York City. "We walk on it, we sleep on it, we work on it; the question is: How do we harness it?"
Google.org hopes that Sausalito, Calif.–based AltaRock Energy can begin to develop the answer with the $6.25 million it is investing in the company. The challenge is steep for such power-producing technology. That is because rather than relying on areas where Earth’s heat comes close to the surface—such as The Geysers geothermal formation in California and similar resources that provide nearly 3,000 megawatts of power at present in the U.S.—AltaRock and companies like it would actually drill deep into the Earth, fracture the subterranean rock to create a reservoir, and then pump fluid through the repository to capture the surrounding geothermal heat.
"The geology is very important," says Paul Thomsen, public policy manager for conventional geothermal outfit, Ormat Technologies in Reno, Nev. "The deeper you drill, the more expensive it is…"
