Residential First Cost - Ground Water (Open-Loop)


The size or capacity of the heating and cooling system to be installed in a home or light commercial application will be the same regardless of the type of system. The installed or "first" cost of a water-to-air (geothermal) heat pump or air-to-air (conventional) heat pump, or a conventional gas, oil or propane furnace with electric central air conditioning are all about the same.

The water-to-air heat pump is the indoor portion of a geothermal system, whether it's a ground-water open-loop or ground-coupled closed-loop system, although they are two different equipment models.

With the ground water geothermal heat pump system, you should consider the incremental or additional cost of installing the well-watersystem. If you have an adequate supply of good quality water, very little added investment may be needed for the open-loop system. It can be as little as the cost of a return or disposal well...$500 to $2000.

In most cases, you will have to install a well system, including the well pump, tank, piping to and from the building, and a disposal well. This cost can add $500 to $1,500 per ton of cooling capacity to the first cost.

Please note: ALL costs are rough estimates only. You must check locally for your costs.

In all cases, you must consider the quality of the supply water now and what it might be in the future, and how disposal will be handled. If it is corrosive or requires careful filtering, or a rejection well is required, these factors will impact the first cost.

The added first cost can usually be justified in TWO ways:

  • First, with longer equipment life. ASHRAE estimates the median life of a water-source heat pump at 19 years compared to 15 years for an air-source heat pump or air conditioner.
  • Second, with tax-free savings in operating costs over conventional systems.

These are illustrated in the segment - Residential Operating Cost Comparisons.