What is Geothermal? Energy from the Ground.

Geo_Earth_Thermal_Heat.pngThere exists an endless form of energy – a true renewable – that resides in the earth beneath our feet and which comes from the sun. We call it Geothermal. The word comes from the Greek – yn (ge), meaning earth, and qεomoς (thermos), meaning hot. Geothermal heat in the ground is the result of two forces: heat rising from the earth’s molten core and solar energy that travels at 186,000 miles a second and reaches our earth, in the form of life-giving light, in about eight minutes’ time.

The earth is a giant solar collector and it absorbs and stores about 50% of the energy arriving on earth from the sun. That underground energy remains at a fairly constant, moderate temperature of between about 40° and 75° Fahrenheit, just below the surface, all year round. Average ground temperatures across North America range from a low of 40°F in Anchorage, Alaska to 71° in Austin, Texas.

Mankind’s ability to tap and use this heat under out feet first required the invention of something called a heat pump, which occurred in 1852, and then the application of the heat pump to actually draw the heat from the ground, first proposed in 1912. However, it wasn’t until the late 1940’s, here in the United States, before the application was field-tested, first in an office building in Portland, Oregon (1946), and then in an Ohio home (1948).

House_Heat.pngWhat emerged from those early experimental applications was a new form of heating and cooling technology, a very simple system that combined a heat pump located inside a building connected to an underground piping loop containing water mixed with an antifreeze fluid (glycol) and installed adjacent to the building. The system operates by transferring the heat in the ground to the building during the cold months of the year and by removing the heat in the building and returning it to the ground during the warm months of the year. This transfer of heat is called geo-exchange.

It took until the 1980s for a geothermal industry to develop and become a part of the heating and cooling marketplace. Today, that market is growing rapidly due to dedicated industry professionals and supporting organizations working to make geo a mainstream technology. Their efforts are getting a big boost because of a number of intersecting reasons including:

  • The high cost of conventional heating & cooling (geothermal is highly efficient)
  • A desire to reduce carbon footprints (geothermal does not burn fossil fuels)
  • Geothermal is a renewable (clean & ever-present)
  • Geothermal produces very comfortable and quiet heating & cooling
  • Geothermal systems are durable & long lasting
  • A 30% federal tax credit applies and extra state-by-state rebates are available


Geothermal is the most efficient and economical way to heat and cool homes and buildings of any kind. It does not use fossil fuels so it is very clean and environmentally friendly. Just as the energy from the sun is endless, so too is geothermal.

Are you ready to Geo?