Geothermal heating reduces carbon emissions, energy costs, and dependence on fossil fuels, and has become a standard in many parts of the world. The US lags behind, however, with geothermal having to fight for the federal incentive “scraps” that solar and wind power have only recently recovered. New developments and a renewed sense of optimism suggest the US is on the verge of a geothermal renaissance in the coming years. Geothermal heating systems access heat retained within the Earth since the original formation of the planet, through the process of radioactive decay, as well as from absorbed solar energy. While electricity-generating geothermal power plants need high-temperatures that are only economically feasible to access in areas where volcanic activity occurs near the surface, geothermal heating, in contrast, is available almost everywhere. Even during cold winters, undisturbed ground below six meters maintains the area’s mean annual air temperature, and that heat may be extracted with a heat […]