Heat Pumps

Heat pumps can provide space and water heating at a lower cost than oil, electricity, LPG and mains gas. There are two main types of heat pump system; air source and ground source.

Air Source Heat Pumps

Air source heat pumps take energy from the air and increase it to a higher temperature. The air is drawn across a water / antifreeze mix which transfers the energy into the refrigerant. When the refrigerant reaches boiling point gases are produced from the reaction and the system then compresses them, to produce the temperature required for a heat exchanger to transfer the heat for use. The heat is transferred to either water – for radiators or under floor heating, or to air which fans disperse around the space.

Ground Source Heat Pumps – 3


Ground source heat pumps use a loop buried underground, to transfer heat from the ground into a building to provide heating to heat water. The ground source heat pump system comprises of three components:-

1. Ground Loop. Lengths of pipe are buried in the ground, filled with a water / antifreeze mix. This fluid is pumped round the pipe absorbing heat from the ground.

2. Heat pump. The heat pump has three parts:-

a. Evaporator – Extracts the heat from the water in the pipe.
b. Compressor – Pushes the refrigerant through the heat pump, compressing the resulting gas to produce the required temperature.
c. Condenser – Transfers the heat to a hot water tank for the heat distributor.

3. Heat distribution system – Under floor heating or radiators to transfer the heat to spaces and the hot water system.

When used as heating systems for the home, heat pumps are often used in combination with underfloor heating, loft insulation, cavity wall insulation and good quality double glazing.

There are a number of government schemes aimed at encouraging widespread take up of green energy solutions. These schemes run for a period of time from 6 months to several years and have offered various amounts of money in the form of grants. Currently active are : –

The Renewable Heat Incentive

This scheme remains open to applications until 31 March 2022 and applications can be made via the Ofgem website.

Are You Eligible?

If you heat your home using a renewable heat source, you could be eligible for this grant in the form of payments. The renewable technologies in question must be : –

  • listed as a Microgeneration Certification Scheme (MCS) certified product
  • issued with a MCS certificate.

To apply people must be owner-occupiers, private landlords, self-builders or registered providers of Social Housing support. Single domestic dwellings are included, although new builds are not.

The Ofgem website has more details about eligibility.


Green Homes Grant

Another grant which runs until March 2022 is the Green Homes Grant, which has been given an additional £1bn. This increase was announced as part of Boris Johnson’s new Ten Point Plan, revealed in Nov 2020. The criteria of the scheme is that homeowners or landlords may apply for up to £10,00 worth of vouchers. These are to be used for renovations to increase the energy efficiency of homes. At least two thirds of the project costs will be covered by the grant, while lower income households will receive the full amount.

Applications can be made here https://www.gov.uk/apply-green-homes-grant

Heat Pump Manufacturers

Manufacturers of heat pumps include Goodman and Kensa Engineering.


Heat Pumps – Air Source, Heat Pumps – Ground Source. Grants for Microgeneration Technologies. Renewable Heat Incentive, Green Homes Grant.