At Home: Use of geothermal heat pumps on the rise

With homeowners exploring more energy-efficient options for their heating and cooling systems, the purchase and installation of geothermal heat pumps are on the rise in the Sunflower State, according to the Kansas Geological Survey, or KGS.

Large-scale “direct use” geothermal systems – which involve using the heat in the water directly (without a heat pump or power plant) for such things as heating of building complexes, industrial processes, greenhouses, aquaculture (fish farming) and resorts – are more common west of the Rockies. However, the KGS informational report indicates that geothermal heat pumps, or GHP’s, for residential and commercial use are increasing in Kansas.

While that news may be encouraging, what exactly is geothermal heat and how does a geothermal heat pump work?

According to the Geothermal Resources Council, “GHP’s use the earth or groundwater as a heat source in winter and a heat sink in summer. Using resource temperatures of 4°C (40°F) to 38°C (100°F), the heat pump, a device which moves heat from one place to another, transfers heat from the soil to the house in winter and from the house to the soil in summer.”

Tim Dugan began Ground Source, Inc., of Holton, in the early 1990’s. He said while the awareness in the geothermal heat pumps has grown since he began installing the systems in homes and small businesses, the science of geothermal heat isn’t new. In fact, he said Oklahoma State University began studying geothermal heat after WWII. He said today, the basic level of knowledge about GHP’s mainly centers around the energy cost savings.

“From 23 years ago to now, yes, there’s more interest,” Dugan said. “From the people we talk to at the home show, they know someone who’s had lower bills (with the GHP). They know it’s good.”

Dugan said he estimates he’s installed 700 to 800 GHP’s in northeast Kansas since the early 1990’s. He said the GHP units he sells and installs initially cost an estimated $20,000. With a 30-percent federal tax credit (Kansas doesn’t offer a tax credit at this time for GHP’s), the cost drops to $14,000 and could decrease even more with additional energy-efficient credits and rebates. Some FHA-backed mortgage loans also have higher loan limits for homebuyers who will install energy-efficient systems and windows.

Using all available credits and rebates, Dugan said if you’ve been a propane customer, you could potentially recoup the cost of your GHP in two to three years. If you’ve been natural gas consumer, it could be four to six years before the GHP “pays for itself.”

Aside from the savings on your heating and cooling bills, Dugan said the GHP’s are quieter than standard HVAC systems and provide a more constant, comfortable temperature level in your home, even during the extremes of summer and winter.

According to information posted on Ground Source, Inc.’s website, “There is no combustion or need to vent exhaust gasses which means our equipment can be installed virtually anywhere.

If you have ductwork already installed in your home, you are starting the race ahead of the pack. If not, we can effortlessly install ductwork so you can enjoy the comfort of geothermal to its full extent.”

Another advantage of the GHP’s is they can be installed inside the home, free from the problems that weather and vandalism can present for traditional outside units.