Ground Source Heat Pumps

Recent environmental and energy issues have begun fueling more interest in renewable energy sources, such as geothermal, which takes advantage of nature. The temperature of the earth a few feet below ground is a constant 50 to 70 degrees everywhere in North America. A geothermal system uses that constant temperature to heat and cool homes.

The system contains hundreds of feet of polyethylene coils buried about five feet beneath the ground’s surface. These coils act as a huge radiator. They contain water with an antifreeze solution that is circulated under 60 pounds of pressure.
The system absorbs and exchanges heat in the ground. The fluid circulating in the pipes absorbs the ground’s heat when the weather is cold to produce warm air for the house. When the weather is hot, the system reverses. Heat is pulled from the building and deposited in the cooler ground to create cool air for the house.

These systems do not burn fossil fuel, so they don’t emit greenhouse gases or contribute to global warming. They are quiet, easy to maintain and extremely efficient. Ritchey said the WaterFurnace system achieves 500 percent efficiency.
Geothermal systems typically deliver four times as much energy as it takes to run the system. In other words, for every one kilowatt-hour of electricity used to run the equipment, four kilowatt-hours of energy are pulled from the homeowner’s backyard. Electricity is needed mainly just to run the unit’s fan, compressor and pump.

This efficiency results in savings for consumers. According to Ritchey, the cost to heat and cool an average 2,500-square-foot home in Fort Wayne with a geothermal system would only be $780 a year. The same home with a high-efficiency natural-gas system would cost $1,497 to heat and cool, he said.

Even homes that already have a traditional furnace system can take advantage of “green” geothermal technology. WaterFurnace’s newest system, called Envision Split, can save homeowners up to 70 percent on their heating and cooling costs, Ritchey said.

It has the highest heating and cooling efficiency rating of any other split product in its class certified by the Air Conditioning & Refrigeration Institute. It is dubbed a “split” system because it works with existing fossil-fuel furnace systems. A split system uses an existing gas furnace for its air handler and forced-air distribution.

Split systems typically handle all of the cooling demand and all of the heating demand, except for extreme cold, when conventional furnaces operate most efficiently. Geothermal units on split systems are typically smaller, and the return-on-investment time is shorter.
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