Used for heat extraction from the ground as the name implies, Ground source heat pumps use pipes for the extraction of its heat which can be transferred to underfloor or heating systems for warm air, heat radiators or for heating domestic water. Thus, they have been used as heat sources for homes during winter and as a sink to remove heat in the summer. This flexibility in function led them to be more commonly called earth-energy systems.
In operation, this type of heat pump distributes antifreeze and water around a loop in the ground. The length of this loop is dependent on your home size and quantity of heat that will suffice your domestic heating needs. Although longer loops are able to trap more heat from below the ground, they however require more space. Ground heat absorbed into the fluid then passes to the heat pump through a heat exchanger and since the temperature of the ground stays relatively constant under the surface, the heat pump can be employed all year round. During summer, however, the function is reversed as the ground source heat pump now takes heat from the indoor environment to the ground by an antifreeze or ground water solution, although a direct expansion ground heat pump uses a refrigerant instead of an antifreeze solution in the ground-heat exchanger.
Ground-source heat pumps come in different designs which could be split or self-contained systems. Split systems allow the addition of the coil to a furnace of forced-air while employing existing blower and furnace, whereas self-contained systems combine the compressor, blower, condenser coil and heat exchanger in a single cabinet.
Ground source heat pumps can also be designed to work with hydronic or forced-air heating systems and can be made for installation to provide only heating, heating with active cooling or heating with passive cooling as may be desired. Heating only ground source heat pumps don’t provide cooling benefits, while heating with passive cooling systems don’t use the heat pump to assist in cooling but use an antifreeze or cool water for this purpose.
Benefits of ground source heat pumps include lowering of fuel bills, especially if you’ve been using conventional electric heating, low carbon emission from homes, minimal maintenance to keep it running, as well being able to heat your home and water. Ground source heat pumps also don’t require fuel deliveries for operation.