The Smithy Farm development has also been fitted with a Ground-Source Heat Pump. This uses a buried ground loop which transfers heat from the ground to a building where it is able to provide efficient space heating. In this instance, horizontal trenches were dug in a large field to the back of the development and spiral coils installed before the trenches were infilled. The field was of a size to enable sufficient coils to be laid to serve two of the three buildings in the development.

This system is now connected to the standard under-floor heating and radiator circuits. It too is capable of keeping constant temperatures and can provide heating and hot water to 55°C.