Cost of Geothermal Heat Pumps
The new 30% federal tax credit, with no cap, significantly reduces the payback period for any geothermal installation, resulting in a tremendous cost reduction. In some cases we have seen the net cost to install a geothermal system, after the tax credit and utility rebate, to be below the cost to install a conventional heating and cooling system.
We start with a phone interview to assess feasibility and determine a preliminary budget range to install a geothermal heating and cooling system. If the preliminary cost range is acceptable to the owner, we schedule a visit to conduct an on site inspection and collect necessary information to develop the custom plan and more detailed cost analysis.
Every project starts with a heating and cooling load calculation per the ACCA Manual J. Once loads are determined, equipment can be selected, duct systems designed or evaluated if they are existing, and borehole lengths can be calculated. These factors drive primary costs.
Geothermal activities that are largely incremental to conventional systems include the site management, drilling, excavating, the ground loops and their installation, grouting, bringing the offsets from the borehole in the yard through the foundation into the house, yard clean up, the inside plumbing and the fluid pumping system.
Most geothermal systems installed in Connecticut deliver heat and cooling through ducts. Increasingly, owners are considering the option of the adding more heating comfort through the use of radiant floor heating which is done through pipes installed under the floor. Ducts are still required for cooling.
Geothermal does not work with hot water baseboard or radiators. Due to the lower operating temperatures of geothermal compared to a boiler, there is not enough surface area for these types of heating systems to generate the heat required for the space.
Every geothermal heat pump needs to backed-up with some form of auxiliary heat since the heat pumps are not sized to do 100% of the load at extreme outdoor conditions. Usually, the system is backed-up with either electric strip heaters installed in the air handlers or hydro-air heat from a fossil fuel (gas or oil) system through hot water coils installed in the ducts. Properly designed systems usually require very little back-up heat since the source of the heat is the ground which, unlike air, is a steady 54 degrees year around.
