There are 2 common types of heat pump available:
Geothermal Heat Pump and Air to Water Heat Pump

Heat Pumps
Believe it or not our environment is a natural source of heat. There is heat in the air, in the ground and in water. Heat pumps are designed to harness this free and renewable heat and use it to provide our central heating and hot water requirements.

This is done by extracting the heat from the air/earth. This heat is then upgraded to a higher temperature, before being delivered to the central heating system and hot water cylinder. Heat pumps also have the ability to do the reverse and provide a cooling system at warmer times of the year.
They are most efficient when linked to a low temperature heat distribution system such as underfloor heating, providing a constant steady temperature. Heat pumps are very economical, capable of cutting your heating bill by up to 70%. For every unit of electricity used to drive a heat pump, you can expect to produce 3-5 units of heat energy.