What is geothermal heating and cooling?Geothermal (also known as GeoExchange) heat pump systems are really solar energy at its best. The sun keeps the soil below the frost level (4-6 feet deep) around 65 degrees Fahrenheit year-round in the Southeast. A system of loops are installed underground with minimal land disruption. Liquid circulates through the loops, absorbing the ground temperature, and passes through a geothermal heat pump that transfers the liquid temperature to the air. Because the system's fluid is already at 65 degrees, only a small amount of electricity is necessary to warm or cool indoor air a few more degrees to the desired temperature. A distribution system circulates the heated or cooled air.
Geothermal heating and cooling systems heat and cool air and water without carbon monoxide and greenhouse gas emission risks associated with fossil fuel heating.
"The average ground-sourced heat pump delivers three to four times the energy they consume," says Popular Mechanics.
every geothermal heating and cooling system has three major subsystems or parts
In winter, the geothermal heat pump extracts heat from the fluid in the earth connection and typically distributes warmed air through a system of air ducts. Cooler air from the building is returned to the heat pump and is re-warmed as it flows through the underground loop. The process is reversed in warmer months, when the earth connection absorbs heat from the building and transfers it to the ground.
three types of heat pump systems for geothermal heating and cooling
direct exchange geothermal:
- Can reduce annual energy consumption more than 40% compared to air-source heat pumps, as much as 70% compared to standard air conditioning,
- eliminates the extra step that water-circulating geothermal units require to convert water heat to a refrigerant, a process that loses heat and requires electricity;
- loops are copper rather than plastic;
- loops have a replacement warranty that includes labor;
- circulates refrigerant
- installation is flexible because the earth loops can be installed horizontally, vertically, or diagonally as space requires.
air-source heat pumps:
"But an indoor unit in its sealed chamber has none of these problems … in place for 20 years … they seem to remain efficient." – Popular Mechanics