Geothermal / GeoExchange^® heating and cooling uses the relatively constant temperature of the earth to heat and cool homes and businesses with 40% to 70% less energy than conventional systems. While conventional furnaces and boilers burn a fuel to generate heat, geothermal heat pumps use electricity to simply move heat from the earth into buildings, allowing much higher efficiencies. The most efficient fuel-burning heater can reach efficiencies around 95%, but a geothermal heat pump can move up to 4 units of heat for every unit of electricity needed to power the system, resulting in a practical equivalence of over 400% efficiency. To learn more about GeoExchange, select a topic from the Resources menu above.

"Geothermal" literally means "heat from the earth", and heat is a form of energy.  So geothermal energy is a resource that we can use to help us live productive and comfortable lives.

Big "G" generates electricity.  In a limited number of locations (think geysers), the earth is hot enough to allow water to be used to generate electricity by passing steam through a turbine to turn an electrical generator.  This electricity can then be used at that site, or transmitted over wires into the North American electrical grid to serve distant towns and cities.  So Big "G" is high-temperature geothermal energy.

Little "g" heats and air conditions homes, businesses and government facilities.  Practically everywhere in North America, the temperature of the earth below the frost line remains relatively constant (close to the surface, the earth temperature does vary a little seasonally with the temperature of the atmosphere).  This steady temperature profile allows the earth to be used as a heat source in the winter, and as a heat sink in the summer.  Geothermal heat pumps use this characteristic to heat and air condition homes, businesses and government facilities by moving heat out of the earth and into the buildings in the winter, and by moving heat out of buildings into the earth in the summer. So, Little "g" is low-temperature geothermal energy.  For more information about geothermal heating and air conditioning, click on the sub-menu links under the Geothermal menu.

Both Big "G" and Little "g" are clean renewable forms of energy that help us to reduce our dependence on other forms of energy and reduce environmental impacts and climate change.