Being in an urban area, there was insufficient space for a horizontal ground loop array for a heat pump. Instead, isoenergy suggested an array of vertical boreholes to collect heat for the heat pump - this is a space-efficient way to install a ground source heat pump system.
isoenergy installed a 60 kW heat pump which was connected to 16 vertical boreholes which collect heat from the ground. The heating system remains docked to the gas-fired boilers for emergency back-up.