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