Integrated heat pump and solar for Dorset Cottage (Summer 2010)

Ground source heat pump, solar thermal and solar PV for 17th Century Dorset Cottage

Sunstone Energy designed and delivered a renewable energy heating system for this Dorset cottage, originally from the 17th century. Solar panels on the roof are designed to deliver approximately 55% of the family’s hot water requirement. This is supplemented by a ground source heat pump which also meets the property’s heating demand, reducing the anticipated energy required for heating and hot water by over 75%. The heat pump collects heat energy from the ground via 600 meters of collector pipe buried 1 metre below the surface. Even in winter this heat energy is sufficient to trigger the refrigeration cycle within the heat pump that results in hot gas transferring heat into water and delivering water temperatures up to 60°C.

Heat Pump and Solar Thermal System Details:

Solar Thermal panels on the original slate roof and a 12kW NIBE Ground Source Heat Pump with ground collector.

In addition to the renewable energy heating system, an array of solar photovoltaic panels was installed on the original south-facing slate roof.

The property owners will receive an income for every kilowatt hour of electricity generated and what they use themselves they will save on their electricity bill. The net annual gain is expected to be over £1,000 and they will continue to receive this, or more if electricity prices rise, for 25 years. Solar PV is particularly advantageous with a heat pump as it helps to mitigate the electricity used to run the compressor. The solar PV alone will save around 1 tonne of carbon every year.

Solar PV System Details:

12 x 190W(p) Schuco Solar PV Modules, 2.28kW system onto original slate roof.