Space heating and domestic hot water for the Purclewan Mill Farm development in Ayr, Scotland, is being provided by air source heat pumps.

The six oak-framed properties have been developed by Hendry Homes and, according to managing director Iain Hendry, they wanted to incorporate a heating system that would minimise carbon dioxide emissions and be cost effective to run.

Six Atria air source heat pumps with capacities of between 6kW and 12kW have been installed in utility rooms or car ports at the development, with the fan unit located outside. They supply space heating, via radiators or underfloor heating systems, as well as domestic hot water. The air source pumps were chosen over a ground source system to minimise the need for carrying out groundwork.

According to the company, for every single unit of electricity, a heat pump generates at least four units of heat – compared to some of the most efficient oil or gas boilers, which convert around 90% of their fuel into heat.