Contact a geothermal heat system installer, preferably one in your area. This is a major job, not a do-it-yourself project. An installer also will help you evaluate the fitness of your home and land for geothermal heat.
Determine the feasibility of adding geothermal heat by examining the land and available water supply with your contractor. Your contractor will use this information to advise you on which type of system you should install.
Choose the type of heat pump system you want to install. Your options will depend on the soil, temperature and water conditions of your property. There are two main categories of heat pump systems: closed-loop and open-loop, and there are three types of closed-loop systems: horizontal, vertical and pond/lake.
All closed-loop systems circulate water through a closed network of underground or underwater pipes. In horizontal systems, the pipes are buried within a few feet of the surface. Horizontal systems are less expensive to install but require a large area and are not suitable for areas with heavy winters where the frost will reach the pipes. In vertical systems, the pipes are drilled vertically into the ground---about 100-400 feet deep. Vertical systems require less land and work well in heavy winters; however, they are often more expensive to install than horizontal systems. Pond/lake systems use coils of pipe in a body of water on your land. The pond or lake has to be deep enough so that the pipes will not freeze.
An open-loop system circulates an available water supply---such as well water---through the heat pump. Open-loop systems are only possible when there is an adequate supply of clean water.
Get an estimate from your contractor. Your contractor also should be able to tell you the estimated electrical costs of running the heat pump. Add up the installation costs and the cost of heating your home over a period of years and compare these to the cost of using your existing heating system. This will tell you how long it will take before you see a return on your investment by way of energy savings.
Apply for financing before inking a deal with the contractor. Many states offer tax incentives for homeowners installing geothermal heating systems.