Tapping the Potential of Deep-heat Geothermal

TerraCOH's vision is grand. The fledgling firm would use carbon dioxide emissions - a nemesis to the planet - to power a ­geothermal energy system, which would in turn produce low-cost, clean electricity. And TerraCOH's patented geothermal technology could serve as a big underground battery, effectively storing renewable - but intermittent - wind and solar energy.