In 2007, private equity firms invested more than $400 million in geothermal energy, which is derived from hot water under the Earth’s surface and can be used for space heating or generating electricity
Why the interest in a form of energy that President Bush repeatedly tried to zero out of the Department of Energy Budget? One reason is the soaring cost of conventional power, like coal and nuclear. Another is the growing awareness of just how much is zero-carbon electricity will need in coming decades.
But perhaps most important for this reemerging technology, in the 2005 energy bill, Congress finally extended the renewable energy tax credit to geothermal “which at 2 cents per kilowatt hour for the first ten years, can account for a third of the cost of a project” — and which will expire in December unless Congress gets its act together (see here)!
The U.S. currently has 3 gigaWatts (3000 megaWatts) of geothermal, one third of the world’s capacity, generating $1.8 billion electricity sales. What is the ultimate potential?
The US Geological Survey estimates the US could generate 150,000 megawatts.
A major 2007 study by MIT on Enhanced Geothermal Systems (EGS) found that it could be a provider of substantial baseload (24/7) power: