Grantley Hall, Ripon, Yorks

Pure Renewables was selected by Wheatley M&E to install a 520kW water source heat pump into northern England’s most prestigious hotel. Wheatley’s extensive remit included the design and project management of the project’s state-of-the art mechanical and electrical installation and called upon Pure Renewables to design and install the renewable heating element of the scheme.

In keeping with the sustainable ethos of Grantley Hall (they even have their own organic laundry), a water source heat pump is emission-free and very efficient. With the property being in a conservation area and listed, there are no externally visible flues, no oil deliveries to organize and no emission of CO2 and other potentially environmentally-damaging gases. Furthermore, Grantley Hall sits above a subterranean aquifer some 90m below the surface. Extensive tests on the quality and temperature of the aquifer water showed it to be a perfect source of energy for the heat pump system with the aquifer supplying a year-round and constant supply of 14 degree water. A well pump delivers this water to a 720 kW plate heat exchanger which in turn transfers the 14 degrees to a closed glycol circuit.

Twelve thousand litres of brine buffer capacity deliver ‘low-grade’ energy to 8x 66 kW Stiebel Eltron heat pumps which convert this to ‘high-grade’ energy for heating and hot water generation. The hotel has a mix of underfloor heating and radiators and 12,500 litres of domestic hot water capacity to serve the 47 guest bedrooms and the hotel kitchens. Pure Renewables chose German company Stiebel Eltron for their  high-quality, reliable and efficient heat pumps, alongwith their excellent pre and post-sales support. Their heat pumps have been used in other notable historical buildings such as the National Trust house at Plas Newydd in Anglesey and Welham Hall in Malton. Via the Stiebel Eltron Internet Service Gateway (ISG), the customer and Pure Renewables are able to remotely monitor the system, make changes as appropriate to maximise efficiencies and performance and to also carry out preservice diagnostics. The system was commissioned in June 2019.

Chris Whitelock, MD & owner of Pure Renewables, remarked “This is a fantastic application for a large capacity heat pump system whereby the CO2 and run cost savings will be significant. Furthermore, zero-emission heating technology is the way of the future for the UK’s building stock and it’s fantastic to be involved in and associated with such a prestigious, forward-thinking client who is investing in the long-term.” Nigel Wheatley of Wheatley M&E commented “Grantley Hall has been a flagship project for us and it has been a pleasure to work with Pure Renewables who delivered their remit on time and to budget.”