A geothermal or “ground-source” heat pump is an electrically-powered device that uses the natural heat storage ability of the earth and/or the earth’s groundwater to heat and cool your home or business.
HOW DOES IT WORK?
Like any type of heat pump, it simply moves heat energy from one place to another. Your refrigerator works using the same scientific principle. By using refrigeration, the geothermal heat pump removes heat energy stored in the earth and/or the earth’s groundwater and transfers it to the home.
Geothermal heat pumps also take advantage of the mild ground temperature for extremely high efficiency cooling. Most systems also include a hot water generater, which diverts a portion of the supplied heat to the domestic water heater. This provides a substantial portion of a family’s hot water needs at a very low cost. Overall, geothermal technology offers the highest cooling and heating efficiencies of any system available today.
DOES IT BOTH HEAT AND COOL?
One of the things that makes a heat pump so versatile is its abitlity to be a heating and cooling system in one. You can change from one mode to another with a simple flick of a switch on your indoor thermostat. Plus, a geothermal heat pump can assist in heating hot water year-round.
A CLOSED-LOOP SYSTEM
The term “closed-loop” is used to describe a geothermal heat pump system that uses a continuous loop of special buried plastic
pipe as a heat exchanger. The pipe is connected to the indoor heat pump to form a sealed, underground loop through which water or an anti-freeze solution - depending on where you live - is circulated. Unlike an open-loop system that consumes water from a well, a closed-loop system recirculates its heat transferring solution in pressurized pipe.
AN OPEN-LOOPED SYSTEM
The term “Open-Loop” is commonly used to describe a geothermal heat pump system that uses groundwater from a conventional well as a heat source in winter and a heat sink in summer. The groundwater is pumped through the heat pump where heat is extracted (in winter) or rejected (in summer), then the water is disposed of in an appropriate manner. Since groundwater is a relatively constant temperature year-round, it is an excellent heat source as well as a heat sink. A well must have enough capacity to dispose of the water passed through the heat pump. A new return well should be installed by a qualified well driller. Likewise, a professional should test the capacity of an existing well before it is used as a return.
