Geothermal Heating and Air Conditioning
October 24, 2011 |
Geothermal heating and air conditioning are heating and cooling systems that use the Earth’s natural energy to heat and cool buildings. Geothermal energy is one of the most efficient heating and cooling sources in the world.
There are really two kinds of “geothermal” energy. The term traditionally refers to heat stored deep within the Earth. But more recently it has also been applied to ground source heat pumps, also known as geothermal heat pumps, which use heat from the sun that is trapped in the soil.
In the first case, the Earth generates and stores heat, some of it left over from the planet’s formation and some produced by radioactive decay. In the second, rays from the sun are absorbed by the ground and stored within a few feet of the surface. Together, these types of geothermal heat make up an alternative energy source that provides slightly less than 1 percent of overall energy consumption worldwide.
Most geothermal heating and air conditioning resources are found in areas with geothermal hot spots, near volcanoes and tectonic plate boundaries. But at proper depths, the Earth provides consistent ambient heat that can be used to generate some heating and cooling energy.
Geothermal energy is tapped for geothermal heating and air conditioning by way of a heat pump. The pump uses a transfer medium, typically water, to exchange heat between the ground and the building. When the building’s ambient temperature is colder than the Earth’s geothermal temperature, the heat pump pumps heat from the ground through the water and into the building. When the building’s temperature is hotter than the Earth’s, the heat pump sends heat from the building through the water and into the ground, creating a cooling effect.
