Geothermal power is getting a closer look from several directions. These new studies are based on "hot rocks" at temperatures of around 150 degrees C (about 300 degrees F) that can be reached by drilling a couple of miles into the earth's crust. This is a much more involved approach than dealing with surface or near-surface geothermal activity, as is used for much of Iceland's power generation.
Google, which has an interest in affordable power to run its growing numbers of server farms, is heavily investing (through Google.org) in research into the development of geothermal power. In the US, Google is the largest funding source for geothermal research.
At the same time, the Australian government is investing nearly four times as much as Google to develop geothermal power for Australia. "An Australian Geothermal Energy Association report this week forecast it could potentially produce 2,200 megawatts of baseload power by 2020, adding that represented up to 40 percent of Australia's 2020 renewable energy target."
MIT scientists estimate that the US could develop 100 gigawatts of generating capacity from geothermal over the next 40 years at a cost of US$1 billion. The Australians' timetable is much more aggressive, and comes with a higher price tag. "The association estimated A$12 billion would need to be invested to develop the 2,200 megawatts of power, but added the cost of generating electricity would fall to acceptable levels by the time commercial projects were up and running."
The amount of energy that could be generated from geothermal power is potentially huge. The Australian group estimates that just 1 percent of the country's geothermal capacity could provide 26,000 years worth of clean electricity.