How Do Heat Pumps Work?

Heat pumps are devices that are becoming increasingly popular to heat and cool homes. They work by transferring heat from one location to another, which can be more efficient and cost-effective than traditional heating and cooling systems. In this post, we'll take a closer look at how heat pumps work.

There are two main types of heat pumps: air-source and ground-source (also called geothermal). Both types work on the same basic principle, which is that heat always moves from hotter to colder objects. Heat pumps take advantage of this by transferring heat from a location where it is not needed (such as outside air or the ground) to a location where it is needed (such as inside a building).

Air-source heat pumps

An air-source heat pump works by using a refrigerant to absorb heat from the outside air. The refrigerant is pumped through a closed loop, which consists of an outdoor unit (which contains a compressor, a heat exchanger, and a fan) and an indoor unit (which contains a heat exchanger). The compressor pumps the refrigerant through the loop, causing it to absorb heat from the outside air and turn into a gas. The gas is then pumped to the indoor unit, where it releases the heat and turns back into a liquid. The heat is then blown into the building by a fan.

One of the benefits of an air-source heat pump is that it can be used for both heating and cooling. In the summer, the process is reversed: the heat pump absorbs heat from the indoor air and releases it outside.

Ground-source heat pumps

A ground-source heat pump works on the same principle as an air-source heat pump, but instead of using the outside air as a heat source, it uses the ground. The ground temperature is more constant than the air temperature, so ground-source heat pumps are often more efficient than air-source heat pumps.

A ground-source heat pump typically consists of a loop of pipes buried in the ground, either vertically or horizontally. The pipes are filled with a mixture of water and antifreeze, which absorbs heat from the ground. The heat is then transferred to the heat pump unit, where it is used to heat the building.

In addition to being more efficient than air-source heat pumps, ground-source heat pumps also have the added benefit of being able to provide hot water for the building.

Whether you choose an air-source or ground-source heat pump, you can save money on your heating and cooling bills while reducing your carbon footprint, however there are upfront costs to consider.

According to Energy Saving Trust, an air source heat pump can cost from around £7,000 - £13,000 and a ground source heat pump could cost from £14,000 - £19,000.

Despite the higher upfront cost of installing the ground source heat pump, these are generally more efficient when heating your home, which will result in a higher fuel saving and lower energy bills.