By Alisha Fowler, Breakthrough Generation

I can't really think of a better headline for this article than one I came across earlier today: "Looking for energy, Google goes to hell." Except, maybe: "Google goes to hell (in search of energy)."

Google's philanthropic arm, Google.org, is in fact sinking $10 million into the advancement of technology that harnesses energy coursing deep below the Earth's surface.

While this technology, advanced geothermal technology (AGT), has not received as much attention as solar or wind, its potential is simply enormous. According to MIT, by investing $1 billion in AGT over the next 40 years, the U.S. could develop 100 gigawatts of electricity that emits zero air pollution and provides even more reliable power than coal-fired power plants.

Scientific American reports that more than 2,000 times the entire annual energy consumption of the U.S. is available deep underground.

With AGT, engineers drill shafts down to hot rocks and pump in water to create steam to power a turbine. Check out this U.S. geothermal resource map to get a sense of the scale of potential power.

Dan Reicher, Google's head of climate and energy initiatives, said that new technology could make extracting heat from beneath the ground a massive contributor to US electricity supplies.

"It's 24-7, it's potentially developable all over the country, all over the world, and for all that we really do think it could be the 'killer app' of the energy world," says Reicher. "Killer app" is a term used in the tech industry to describe an application that revolutionises a field and creates new opportunities.

And Google.org is keeping the money in California, at least for now. The bulk of its first geothermal investment - $6.25 million - will help finance AltaRock Energy of Sausalito. The other $4 million will go to Potter Drilling in Redwood City, which employs a hard rock drilling technology.

AltaRock hopes to develop technology that can generate electricity in a wider range of geographies than conventional geothermal ones. "If you drill deep enough anywhere you can get to hot rock," says Reicher.

With Google's high profile announcement and investment, perhaps more of our country will pay attention to the clean energy potential of advanced geothermal.