The air around us contains an almost limitless source of free energy. Even at low temperatures air contains a surprising amount of heat. Making use of this energy using an air source heat pump (ASHP) is in some ways a simpler proposition than using the ground source alternative. The air is simply blown across a heat exchanger using a fan. No ground energy array is required, making the implementation simpler and therefore cheaper.

The drawback of the air source heat pump is that its efficiency is related to the outside air temperature. As the air temperature drops so does the efficiency of the heat pump. Whereas a ground source heat pump (GSHP) can maintain efficiency levels of over 400% the efficiency of an ASHP can drop below 200% when the outside temperature is particularly low. However, over the course of the heating season an ASHP can deliver efficiencies of 350% or greater. ASHP systems are often used in combination with some form of secondary heating to cope with particularly cold days.

The noise from the fans of the ASHP can potentially be an issue for nearby properties and for this reason ASHP’s currently require planning permission unlike GSHP’s.

Compared with central Europe (where air source heat pumps are widely used), the UK has a relatively moderate winter climate. With average winter temperatures of around 5°C the seasonal performance of an ASHP can compare favourably with ground source heat pumps, without the additional cost of a ground loop system having to be installed. The air as a source of heat energy is especially useful when space is at a premium.

An air source heat pump can be a very effective way of heating a swimming pool. When a pool needs heating the outside air temperatures are often quite high meaning that the ASHP will operate very efficiently. Consult us for more information on the use of heat pumps for swimming pool applications.