In October, the Bureau of Land Management said it planned to open more than 190 million acres of federal land in California and 11 other Western states for new geothermal development.
Nevada, the nation's No. 2 geothermal producer, has 45 new projects underway, said Lisa Shevenell, director of the Great Basin Center for Geothermal Energy at the University of Nevada in Reno. An August lease sale of Nevada lands by the federal bureau brought in a record $28.2 million.
"I've been at this 25 years, and I've never seen anything like it," said Shevenell, a research hydrologist. "Money is falling out of the sky."
Geothermal has been harnessed for industry since at least the 1820s. Operators tap natural reservoirs of scalding water and steam trapped thousands of feet underground, drilling wells to bring the heat to the surface to power turbines that feed electricity generators.
Costing about 4 to 7 cents a kilowatt-hour, Taylor said, geothermal is competitive with wind power and significantly cheaper than solar. Geothermal facilities occupy a fraction of the space required by wind and solar farms. The energy is also more reliable. Plants crank electricity around the clock, irrespective of whether the sun is shining or the wind is blowing.
This so-called baseload generation is coveted by power companies, which are under pressure to boost their use of green energy. California utilities must generate 20% of their electricity from renewable sources by 2010. Nevada utilities must hit that target by 2015. Geothermal is a cornerstone of that effort, accounting for about two-thirds of the renewable portfolio of NV Energy, Nevada's biggest utility.
"It's a 24/7 predictable supply," said Thomas Fair, the company's head of renewable energy. "That means a lot to a utility."
Greenhouse gas emissions are minimal in geothermal operations, and the size of the fuel supply defies imagination. There is 50,000 times more heat energy contained in the first six miles of the Earth's crust than in all the planet's oil and natural gas resources, according to the environmental organization Earth Policy Institute.
The challenge is extracting it. Geothermal energy production requires three things: heat from the Earth's core, fractured rock to make it easy to get to and water to transport the heat to the surface.
Traditionally, developers have sought out pockets of hot water and steam hidden underground. Prime areas lie along continental plate boundaries, which is why California is such a hotbed.
