Geothermal technologies take advantage of the relatively constant, year-round temperature of 50 degrees that exists just a few feet below the earth’s surface. Geothermal heat pump systems can draw heat up from the earth in winter, and pump warm air down in the summer, decreasing a home or building’s energy use and its reliance on fossil fuel. To expand the use of geothermal-based heating and cooling, UW–Madison researchers are developing new and more efficient geothermal designs and methods.