Hex Energy retrofitted two 420KW Ground Source Heat Pump (GSHP) systems at a college in England, with installations at two of its campuses. Part of the Public Sector Decarbonisation Scheme (PSDS), these systems provided the majority of the heating and hot water needs for the campuses, supported by existing gas boilers for additional heating if required.
Each GSHP setup included a new, purpose-built plant room housing the heat pump, an external 20,000-litre thermal store, and necessary hydraulic connections to the existing heating and hot water systems. The ground heat exchangers comprised 40 boreholes, each drilled to a depth of 200m beneath the car park, connected in parallel through submanifolds and balanced with valves.
The heat pump system, with a nominal output of 395kW, featured a R1234ze screw compressor with continuous capacity control between 50% and 100%. It included an integral microprocessor controller and a user-friendly touch pad interface, allowing easy programming and monitoring. The system was connected to the campus Building Management System (BMS) for seamless operation.
This project underscored the college’s commitment to sustainability and energy efficiency, showcasing the effective use of ground source technology in educational institutions.
