Heat Pumps

Ground source heat pumps use pipes buried in the garden to extract heat from the ground whereas Air source heat pumps absorb heat from the outside air. This heat is usually used to heat radiators or underfloor heating systems and hot water. 

Beneath the surface, the ground stays at a fairly constant temperature, so a ground source heat pump can be used throughout the year - even in the middle of winter. An air source heat pump extracts heat from the outside air in the same way that a fridge extracts heat from its inside. It can extract heat from the air even when the outside temperature is as low as minus 15° C. 

Heat pumps have some impact on the environment as they need electricity to run, but the heat they extract from the ground, air, or water is constantly being renewed naturally.