One of the ways to analyze this is by using a computer program as a tool called GeoAnalyst. Since houses are different in many ways it becomes a very specific question that needs to be individually looked at. This program allows you to put in variables and get results based on those variables.
For demonstration purposes let's look at an example. This example will be for a 2,500 square foot home. Using a GeoComfort GST048 4 ton unit, we'll call this System1, the total of that system comes out to project an annual operating cost of $853.00. The second system uses a 95 percent efficient propane gas furnace and a 13 SEER air conditioner, which we'll call System2. For that system the program shows an annual cost to operate of $2,448.
The operational cost savings would be $1,595 per year using the geothermal system (System1). This example uses $.09 per kwh for electricity and $1.90 per gallon propane gas. As we know the cost of propane can and does fluctuate depending on demand, but electric rates stay pretty consistent. Of course you would need to adjust those rates depending on what area of the country you live in and the current utility rates.
Although the geothermal system (System1) is more money up front to install, the saving on this example shows that this house should be paid back for the initial cost difference of the system in savings on energy in 2.25 years. After that payback your savings in energy costs would be that amount of difference every year. The bottom line is that geothermal saves lots of dollars.
So when you are checking on paybacks and utility costs, ask your reputable heating contractor to show you how your specific home will be affected, and what you can expect to save in utility costs.
Robert Johnson is the co-owner of from Brogard Plumbing, Heating & Excavating in Henning, Minn. He's worked in plumbing and heating for over 20 years and has been installing geothermal systems for 11 years. He has deep expertise in geothermal and plumbing, having had his journeyman's plumbing license for the past 19 years.