StoryImage( ‘/Images/Story//Auto-img-111159644315914.jpg’, ‘Photo by Dr. Sonia Vogl’, ‘Site of Tom Bartuschs new home in Rockford where workers install underground plastic tubing for a geothermal heat pump system by Rockford Geothermal.’);
StoryImage( ‘/Images/Story//Auto-img-111159784918314.jpg’, ‘Photo by Dr. Sonia Vogl’, ”);
StoryImage( ‘/Images/Story//Auto-img-111159792314778.jpg’, ‘Image courtesy of www.zzfit.com.’, ‘A geothermal heat pump system (GHP) is a kind of highly efficient and energy-saving air-conditioning system, which uses a shallow geothermal source (i.e., geothermal energy, mainly refers to surface and underground water and soil) for both heating and refrigerating.’);
Rockfords newest geothermally heated and cooled home is being built just northwest of the intersection of Mulford and Guilford. Sophisticated technology uses what people have known since they sought shelter in caves: the earth is warmer than air in winter and cooler in summer. Six 400 foot loops of plastic tubing filled with water and a nontoxic antifreeze will transfer the earths nearly constant temperature and move it through a heat pump to heat and cool the home. The loops are about 20 feet underground.
Tom Bartusch, owner of the home, estimates that his 6 ton system will cost $13,000 more than the lowest priced conventional heating system but expects to recover the additional costs in about five years. The installer, Rockford Geothermal, guarantees power bills of no more than $900 per year for the first five years and will pay any amount above that. After five years, the owner can request an infrared photo of the house to look for heat leaks.
Four thermostats in the 3,200-square-foot house and six adjustable operating speeds on the water furnace provide efficient area heating and cooling.
The home includes other energy-saving qualities. Large south-facing windows draw warmth from the winter sun. North, east and west walls are built with 2 by 6s with an R23 insulation rating. The ceiling uses batt insulation to attain an R52 rating. Closed cellulose insulation is sprayed on basement walls.
Bartusch stated: Im looking forward to being able to control those heating and cooling bills!
According to Dirk Dypold of Advanced Geothermal in Elgin, a 2,400-square-foot well-insulated house needs 4 tons of heat pump capacity. Four hundred feet of looped pipe provide about 1 ton. The pipe can either consist of a deep single loop bore or multiple horizontal loops.
Costs of an installation are about $4,000 per ton. Dypold calculates his home unit cost $6,000 more than a gas furnace. He estimated savings of $1,000 per year on heating, which would make the unit pay for itself in six years. However, a rise in gas prices cut the payback time to four years.
At our latitude, the earths temperature is stable around 8 feet below the surface. Dypold goes down several feet deeper as added protection against an unusually cold winter.
Over the course of a long, cold winter, the water temperature in the pipe drops as it passes cooler water through the surrounding ground. Eventually, the temperature of incoming fluid is near freezing; removing several degrees of heat from it could lower its temperature enough to freeze the heat pump itself. Antifreeze prevents this from happening. At extremely cold outdoor temperatures, such as minus 10 degrees Fahrenheit, electric resistance heating takes over.
When operating in a geothermal mode, the amount of heat extracted is three times the amount of electrical energy needed to operate the unit.
Dypold sees geothermals low electrical demand for cooling as a major benefit as it helps avoid the strain on electrical systems from traditional air conditioners. Efficient fans simply blow over the coils filled with cool water and cool the home.
Since geothermal systems are big electrical consumers, their rates are adjusted. For nine months of the year, they pay 8.6 cents for the first 400 kilowatts and only 3.2 cents for any over that amount. The cost effectiveness of these systems is dependent on low-cost electricity and high natural gas prices.