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Geothermal energy originates from the heat retained within the Earth's core since the original formation of the planet, from radioactive decay of minerals, and from solar energy absorbed at the surface. Due to recent advances in heat pump performance, this is now a rapidly growing market.
Geothermal heat pumps (GHPs) are a relatively new technology that can save homeowners money. These ground-source heat pumps use the natural heat storage capacity of the earth or ground water to provide energy efficient heating and cooling. GHPs should not be confused with air-source heat pumps that rely on heated air.
Geothermal heat pumps use the relatively constant temperature of the ground or water several feet below the earth's surface as source of heating and cooling. Geothermal heat pumps are appropriate for retrofit or new homes, where both heating and cooling are desired. In addition to heating and cooling, geothermal heat pumps can provide domestic hot water. They can be used for virtually any size home or lot in any region of the U.S.
A geothermal heat pump system consists of indoor heat pump equipment, a ground loop, and a flow center to connect the indoor and outdoor equipment. The heat pump equipment works like a reversible refrigerator by removing heat from one location and depositing it in another location. The ground loop, which is invisible after installation, allows the exchange of heat between the earth and the heat pump.
Geothermal heat pumps can be open- or closed-loop. Open-loop systems draw well water for use as the heat source or heat sink, and after use, return the well water to a drainage field or another well. Closed-loop or earth-coupled systems use a water and antifreeze solution, circulated in a ground loop of pipe to extract heat from the earth.
Ground loops can be installed in a vertical well or a horizontal loop. Vertical wells are usually more expensive and used where space is limited. The length of loop pipe required will vary with soil type, loop configuration, and system capacity. Loop length can range from 250 to 1,000 feet per ton of capacity.
Special heat pump features can include variable speed blowers and multiple-speed compressors. These features can improve comfort and efficiency in areas where heating and cooling loads are quite different. Add-on features include the capability to produce hot water.
Desuperheaters can be added to supplement the production of domestic hot water when there is a demand for space heating or cooling. These devices make use of excess heat during the cooling cycle and use some of the heat during the heating cycle to supplement hot water production. Dedicated water heaters can be added which operate whenever there is a demand for hot water.
Geothermal heating can be more efficient than electric resistance heating. These systems are also typically more efficient than gas or oil-fired heating systems. They are more energy efficient than air-source heat pumps because they draw heat from, or release heat to, the earth, which has moderate temperatures year round, rather than to the air (which is generally colder in winter and warmer in summer than the earth, resulting in less effective heat transfer).
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Stimulus Bill Increases Homeowner Tax Credit 30% tax credit for homeowners who install geothermal heat pump systems in 2009 and later years.
For systems placed in service in 2008, the $2,000 lilmit still applies. So, for example, if a homeowner pays $15,000 for a geothermal heat pump system installed in 2009, a tax credit of $4,500 could apply.
For systems placed in service in 2008, use IRS 2008 Form 5695 for the Residential Energy Efficient Property Credit to claim the $2,000 tax credit for Energy Star geothermal heat pumps.
If you use TurboTax, look for the "Home Energy Credits" topic under Personal Deductions and Credits for Your Home. TurboTax provides an input box to enter the amount you paid for Geothermal heat pump property in 2008. As usual, contact your tax professional for applicability to your specific situation. |
