You don’t need super high temperatures to harness geothermal energy. Under the right circumstances, a much smaller thermal gradient can be used as well. If we start digging, we’re guaranteed to find heat. It’s getting that heat to the surface where we can use it without spending more energy than we can actually get out of it -- that's the tricky part. We visit South Africa, Denmark, and upstate New York to learn about the not-so-hot geothermal resource that's beneath our feet all over the world.

Closing the Gap is hosted by Gwen Holdmann and edited by Jennifer Pemberton. This episode was produced by Liz Smith. Music is from Blue Dot Sessions.