| Geothermal heat pumps are a relatively new | | | | from the earth. |
| technology. This technology can save | | | | Ground loops can be installed in a vertical well or a |
| homeowners soe energy bill money. These | | | | horizontal loop. Vertical wells are usually more |
| ground-source heat pumps use the natural heat | | | | expensive and used where space is limited. The |
| storage capacity of the earth or ground water to | | | | length of loop pipe required will vary with soil type, |
| provide energy efficient heating and cooling. | | | | loop configuration, and system capacity. Loop |
| Geothermal heat pumps use the relatively | | | | length can range from 100 to 300 meters per ton |
| constant temperature of the ground or water | | | | of capacity. |
| several meters below the earth's surface as | | | | Special heat pump features can include variable |
| source of heating and cooling. Geothermal heat | | | | speed blowers and multiple-speed compressors. |
| pumps are appropriate for retrofits or in new | | | | These features can improve comfort and |
| homes, where both heating and cooling are | | | | efficiency in areas where heating and cooling loads |
| desired. In addition to heating and cooling, | | | | are quite different. Add-on features include the |
| geothermal heat pumps can provide domestic hot | | | | capability to produce hot water. |
| water. They can be used for virtually any size | | | | Desuperheaters can be added to supplement the |
| home or lot in almost any region with the | | | | production of domestic hot water when there is a |
| existence of ground water. | | | | demand for space heating or cooling. These |
| A geothermal heat pump system consists of | | | | devices make use of excess heat during the |
| indoor heat pump equipment, a ground loop, and a | | | | cooling cycle and use some of the heat during the |
| flow center to connect the indoor and outdoor | | | | heating cycle to supplement hot water production. |
| equipment. The heat pump equipment works like | | | | Dedicated water heaters can be added which |
| a reversible refrigerator by removing heat from | | | | operate whenever there is a demand for hot |
| one location and depositing it in another location. | | | | water. |
| The ground loop, which is invisible after installation, | | | | Geothermal heating can be more efficient than |
| allows the exchange of heat between the earth | | | | electric resistance heating. These systems are |
| and the heat pump. | | | | also typically more efficient than gas or oil-fired |
| Geothermal heat pumps can either be open- or | | | | heating systems. They are more energy efficient |
| closed loop. Open-loop systems draw well water | | | | than air-source heat pumps because they draw |
| for use as the heat source or heat sink, and after | | | | heat from, or release heat to, the earth, which |
| use, return the well water to a drainage field or | | | | has moderate temperatures year round, rather |
| another well. Closed-loop or earth-coupled | | | | than to the air (which is generally colder in winter |
| systems use a water and antifreeze solution, | | | | and warmer in summer than the earth, resulting in |
| circulated in a ground loop of pipe to extract heat | | | | less effective heat transfer). |