When you hear about geothermal power plants (ie using the heat from the Earth’s crust as a cleaner and more renewable source of energy than coal-fired and nuclear power plants), you typically hear about them only in Iceland. Turns out, the US is the world’s largest producer of geothermal energy. But no one really knows or talks about it here as an alternative energy source.

A US Department of Energy-sponsored report – [pdf], released today, is trying to change that.

According to the report’s 18 authors, led by MIT’s Jefferson Tester, this is the most in-depth look at the feasibility and the pros and cons of more widespread use of geothermal energy in the US. They conclude that more geothermal power plants in the US can fulfill a small portion of our energy needs at competitive prices, with reasonable investments and with minimal environmental impacts (ie low emissions) in just the next 10 to 15 years, compared to fossil fuel-based sources.

It recommends more field trials at specific sites for potential geothermal plants, more exploration of deeper geothermal deposits and more pro-geothermal policies, among other things.

Reuters wrote a piece about this today and boils this 400+ page report down to some hard numbers about how much energy geothermal plants could provide and at what cost. WBUR also ran a piece this morning.

Addendum (Jan 23): news@nature wrote a nice piece on this as well.