Geothermal Heating and Cooling Movement Gaining Ground
Geothermal systems are widely recognized as a quiet, long-lasting alternative for home heating and cooling. They can be designed in a zoned system to serve different parts of a house with maximum comfort.
Geothermal heating and cooling has been well understood since the 1950s, but it wasn't until the 1970s that the technology was available to make it efficient and affordable. Geothermal heating and cooling takes advantage of the fact that a few feet below the surface, the earth remains at a fairly constant, moderate temperature. If you've ever been in a cave, you know what it feels like. No matter the outside temperature, the cave stays at the same temperature level deep underground.
Geothermal heating and cooling systems take advantage of the stable temperature (about 55°F) underground using a piping system, commonly referred to as a "loop." The water circulates in the loop to exchange heat between the earth and the home using a ground-source heat pump. The loop contains water and an anti-freeze mixture to maximize heat transfer. Depending on the site, loops can also use ground water to circulate through the pump.
The same geothermal heat pump can provide heating and cooling, as well as hot water with optional equipment, at remarkably high efficiencies. In fact, geothermal heating and cooling systems are 400 percent to 600 percent efficient and can cut heating, cooling, and hot water costs by up to 80 percent.
This infographic from GeoComfort Geothermal Systems reviews some of the benefits of geothermal heating and cooling that can be used in new and existing homes.