Case study: energy saving heat pumps for new homes

To reduce the environmental impact of heating homes while working towards achieving net zero status by 2030, work has started on installing ground source heat pumps at two of Gravesham Borough Council’s housing developments.

The aim of this project is to improve the energy efficiency of homes to significantly reduce their carbon footprint, especially during colder months. The project also aims to reduce the cost of energy bills for tenants by using a renewable energy system, provided by ground source heat pumps.

How heat pumps work

A ground source heat pump is a renewable heating system that extracts low-temperature solar energy stored in the ground or water using buried pipework. It compresses this energy into a higher temperature. A ground source heat pump can provide a building with 100% of its heating and hot water all year round.

What they did

Water tubes were installed deep underground at housing developments in Merston Court and Hermitage Road in Higham. The pipes are heated by the surrounding soil. The liquid is then passed through a compressor which raises its temperature. It then flows into the home to be used in radiators, underfloor heating and to generate heat for hot water.

What they achieved

The introduction of a ground source heat pump at Hermitage Road is expected to see a saving of 24 tonnes of carbon over 20 years, while at Merston Court the figure is 13.67 tonnes over the same period, resulting in a combined 37 tonnes of carbon saved in just two residential areas.

Gravesham Borough Council plan to increase the energy efficiency of more than 350 homes following a successful application for over £800,000 from the Government’s first wave of financing with the social housing decarbonisation fund.

The council is one of only two in Kent to successfully apply to the fund and will receive a grant of £823,337. Gravesham will contribute a further £800,170 to the project, meaning a total of £1,623,507 will be spent on upgrading the energy performance of 364 council-owned properties in the Borough in 2022 to 2023.

You can use our online tool to find out what energy efficiency measures could be installed for your home, and what relevant financial support is available.


Cllr Jenny Wallace, Gravesham Borough Council’s Cabinet Member for Housing Services, said: “Our independent living homes at Merston Court currently rely on electric storage heaters, which are inefficient, expensive to run and have reached the end of their lives, while the flats at Hermitage Road have gas boilers.

“These new ground source heat pumps will improve the energy efficiency ratings of all these homes and significantly reduce their carbon footprint, and bring real financial benefits for our tenants.”

Get involved

If you have any questions about our case study, or have any ideas for future trials we could run, email