Open Loop Geothermal Systems

Most of the time, geothermal heating and cooling systems rely on a closed loop. This is a loop that is installed underground that contains anti-freeze, which is used to distribute heat from the house into the Earth during the hot months of the year and to take heat from the Earth and bring it to the house during the cold months of the year. Some lucky homeowners, however, will be fortunate enough to have the option of installing an open loop system. This is, in many ways, a very desirable situation for anybody who has geothermal heating and cooling installed, as it can cut down on costs. 

The Difference

In some areas, open loop geothermal heat pumps are able to function because of the high water table. The reason for this is because the pump can draw water from the water table, use it to either distribute heat to the house or draw heat away from the house and then deposit that water back into the water table. Because the geothermal system is closed other than the entry and exit points, it is not introducing pollutants into the water table, which is important to individuals who are concerned about the environment.

Another real advantage of open loop geothermal systems is the fact that they require no anti-freeze to function. Even though there are environmentally friendly types of anti-freeze available on the market, some people do have reservations about these substances. An open loop geothermal system is simply using water that is already present in the earth as a medium for taking or giving heat from or to the home. This is an enormously efficient way to go and, it provides an affordable way to get geothermal heating and cooling installed in your home.

Geothermal Heat Pump Suitability

You will generally see open loop geothermal systems installed in commercial buildings. They can also work wonderfully for residential buildings, however, and homeowners who are able to install them will typically be very pleased with the results. The one part of these systems, sometimes referred to as pump and dump systems, that homeowners might want to be wary about is the fact that they are dependent upon a potentially changing water table for their geothermal heating and cooling. In a closed system, there will always be enough anti-freeze to accommodate the heating and cooling needs. Water tables can be variable and there may be situations where an inadequate amount of water remains to keep the system working efficiently.

Open loop geothermal heat pumps and open loop geothermal systems are both options that a qualified contractor can help you learn about. Whether or not they are suitable for your area will be something you will have to discuss with them. Every homeowner’s situation is somewhat different and only an expert will know for certain whether or not this arrangement is suitable for you. If it is, however, these systems can be very affordable and can reduce some of the cost of installing the ground loop. They do have their risks, however, so you'll want to make this decision carefully.

by - Phillip Rye

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