Geothermal power plants could supply the energy needs of the U.S. thousands of times over, concludes an 18-member panel led by the Massachusetts Institute of Technology. Geothermal stations create electricity by relying on liquid or vapor heated deep within the earth. The panel proposes to construct many new geothermal power plants, drilling down into the high-temperature bedrock, creating an open reservoir and pumping liquid into it to be heated. The researchers estimate that some 13 trillion trillion (1024) joules lurk deep underneath U.S. soil and that 1.5 percent of that energy is recoverable, without taking cost into account. More than 100 gigawatts of geothermal power (one tenth of the current U.S. electrical generation) could be developed for $1 billion during the next 40 years—at the full cost of one carbon-capturing coal-fired power plant or one-third the cost of a new nuclear generator. The challenge: not to lubricate any faults that could trigger earthquakes as has occurred in Basel, Switzerland.
This article was originally published with the title "Hot Rocks" in Scientific American 296, 4, 28 (April 2007)