By Barbara Baird, September 2008

• Introduction
• How does it work?
• Closed & open loop systems
• What's the cost comparison?
• Examples & where to find contractors
• Download the full article as a

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They are called ground-source, geoexhange, earth-coupled, ground-water, ground-water assisted, ground-water-source or water-to-water. But don’t let the variety of names pertaining to geothermal systems confuse you because it’s all the same idea. It’s all about using an environmentally friendly, efficient type of heat pump to acquire the earth’s energy and transfer it into your living and working spaces.

People choose ground-source heat pumps (GSHPs) to save energy dollars. Other pluses include the environmentally friendly nature of the system—emitting no pollutants onsite—along with a long warranty and quick and quiet delivery of hot or cool air. Since the compressor is installed inside the house and makes the same amount of noise as a refrigerator, there is no noisy outside unit to care for or disturb the peace and quiet.

Gary Heavin of Doolittle, Mo., says, “We have 3,600 square feet on one level and I can conservatively say that our ground-source heat pump has saved us $200-$250 per month or more.”

His neighbor over in Rolla, Mo., Bill Franklin, has owned two houses with GSHPs in the past 16 years and wouldn’t be without one. He says, “The reasons I like ground-source heat pumps are because there aren’t a lot of maintenance expenses and my utility bills, on a building of 8,000 square feet maintaining 68 to 70 degrees, run about $212 per month on average.”