Geothermal power will get a boost today when U.S. Energy Secretary Bill Richardson announces a goal of generating as much as 10 percent of the West’s electricity from geothermal sources by 2020. Richardson will announce $4.8 million in grants to advance research in geothermal energy, a renewable source that taps heat energy from under the Earth’s surface. The Western U.S., Nevada in particular, has more geological potential for geothermal energy than other regions. California is now the top producer of geothermal power in the U.S., getting nearly 7 percent of its electricity needs from underground heat reservoirs.