The geothermal heat pump is gaining in popularity among homeowners who are seeking an efficient, sustainable, and clean energy resource to heat and cool their homes. Given the environmental aspect of using a geothermal system, federal, state, and local governments have established tax benefits and low interest loan programs that can make going geothermal both cost effective and earth friendly.
In fact, a geothermal heat pump gets its power to heat and cool directly from the very earth we walk on. Just 10 feet below the surface, depending on latitude, the earth holds its temperature steady at 45F to 75F degrees, no matter what is happening on the surface in the way of frigid temperatures or heat waves. So the ground is warmer than the air in winter and cooler in the summer.
A water-based geothermal heat pump uses a system of pipes that are buried shallow in the ground to circulate the water or other fluids. The system is made up simply of these pipes, duct work or an air delivery system, and a ground heat exchanger. During the winter, the pump removes the heat from the heat exchanger a pipes it inside. In the summer, the system reverses and it pump removes heat from the air through the ground heat exchanger.
Using this system, these types of heat pumps can cool and heat a home with a 300 to 600 percent efficiency compared with air source heat pumps that run at 175 to 250 percent efficiency, according to the U.S. Environmental Protection Agency. A dual-sourced heat pump, or one that combines the best of both air and geothermal, is less efficient that a totally geothermal system, but can cost less to install and still maintains a higher efficiency than air heat pumps alone.
Installing a geothermal system is decidedly more costly than an air heat pump system, several times more costly. However, the EPA estimates that homeowners can make up the cost in five or 10 years of use. Also consider the lifespan of the unit, which is about 25 years for the internal components and as much as 50 years and more for the ground loop parts, the EPA suggests, making it completely sustainable.
To encourage homeowners to take advantage of this clean energy resource, the federal government as well as state and local governments have come up with a series of incentives, from Energy Star low interest loans for the purchaser, to tax credits that go directly to the consumer in the year of purchase. Anyone considering a geothermal system should definitely look into benefits that both the federal and local authorities may offer.
Once you decide to invest in geothermal energy, you will have to select between four types of systems. There are the closed loop systems — vertical, horizontal, and pond/lake. Another type, the open loop, uses a water source to draw from and returns the water to the pond or lake. All systems are available for residential use, but will depend on such factors as climate, type of soil, local ordinances, and local installation costs.