How is heat transferred between the earth, air or water into the home?
The earth has the ability to absorb and store heat energy. At a metre depth the temperature of the earth is approximately 6 Centigrade all year long. To use that stored energy, heat is extracted from the earth through a liquid medium (groundwater or an anti freeze solution), which is then pumped, to the heat pump or heat exchanger from the ground collector, buried underground. The liquid medium at 6C heats a gas, which is then compressed to raise its temperature. The exchanger transfers the heat from the gas to the water that will eventually circulate through the underfloor piping to heat your home. The maximum water temperature achievable from low temperature Heat Pumps is approximately 55C, although no more than 35 – 40C will be required to provide the heating. Running the Heat Pump at lower temperatures will result in lower operating costs. Similarly, it is also possible to extract heat energy from the air, rivers, lakes and vertically drilled wells.