Geothermal heat pumps (GHPs) are also known as ground-source, GeoExchange, earth-coupled or water-source heat pumps are in use since the late 1940 ‘s. The princip they work on is using the constant temperature of the earth in its depths for the needs at the moment outside at that air temperature. Depending on latitude, the temperatures of the earth range from 45°F (7°C) to 75°F (21°C). That means that the ground temperature is warmer than the air outside in the winter and cooler than the air in the summer. The GHP takes all the advantages of this fact by exchanging heat with the earth through a ground heat exchange. Four basic types of ground loop systems are used today: horizontal, vertical, pond/lake (closed-loop systems) and open-loop system. Depending of the climate conditions in the site, available land, soil conditions and  installation costs, you can choose the best option for your home.

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