Geothermal energy's promise and problems

Google-funded research shows U.S. potential is huge, but extraction could cause quakes - Geothermal energy is touted as one of the few renewable resources that could be used for base-load (round-the-clock) power generation: Earth's heat is always on, and it's not dependent on the vagaries of wind or sun. New research from Southern Methodist University–sponsored by Google's philanthropic arm–suggests massive potential for geothermal power in the United States. But exploiting that resource will be slowed by the cost of the technology–and the fact that it can cause small earthquakes.