Mr Smith, GSHP, Lostwithiel

We installed a ground source heat pump, central heating system and a solar panel array for this historic building.

It was a very large project, the property was stone built over 100 years ago, without a cavity it is important that thermal bridging is taken into consideration on the heat loss. Upgrading insulation or the single glazed windows would not be an option on a grade 1 listed property. The heat loss report was over 21kW at -0.2°, and the power to the property was a single phase supply.

After lengthy discussions with Western Power Distribution we were granted permission to install a ground source heat pump with the capability of producing 26kW of power on a single phase supply. It is rare that an application for a ground source heat pump with such a large output is permitted, the reason for this is because of the start up current which in some cases can be too high for the infrastructure. This is not the case when it comes to the IDM (link). This property is situated within 20 meters of the Fowey river and on our initial assessment it was difficult to ascertain the soil type, identifying the soil type is essential because we need to know how much energy can be extracted to satisfy the heat demand.

Once the soil type was identified we could then accurately calculate the number of boreholes needed and the depth that would be required to deliver the heat needed to satisfy the properties heat demand. A thermogeological survey of the site was conducted. The report confirmed that we would be drilling into ‘fractured Dartmouth beds’ with a thermal conductivity of between 1.9 and 2.6 W/mk.