There are a few sources of power that are “free” here on Earth, namely wind, solar, hydro, and geothermal. Humans have been tapping hydro and wind for millennia, and we’re getting pretty good at harnessing the power of the sun. But with geothermal, we’re still not expertly exploiting the heat that’s generated deep within the planet.
Most commercial-scale geothermal installations are in geologic hotspots like Northern California and Iceland. At a smaller scale, many homeowners have drilled shallow wells or buried loops in their yards for heating and cooling. But to truly unlock geothermal’s potential around the globe, and do so profitably, we’ll need new ways to drill deep down and draw the Earth’s hea …
