Designed to de-steam the current heating system, and deliver guaranteed carbon savings of 2,179 tonnes per year, it will use a ground source heat pump and thermal store, combined with solar arrays to maximise energy efficiency. The innovative new scheme is the first healthcare site where Veolia has implemented this type of design in the UK, and will help the hospital meet the NHS carbon reduction targets for 2030. Since 2003, Veolia has been managing combined heat and power at the hospital that provides a wide range of diagnostic services, outpatient clinics and low risk surgery. The new upgrades will use acombination of technologies to optimiseefficiency and balance the electrical andthermal requirements.The new scheme combines a 1,400kWground source heat pump system with a 70,000 litre thermal store to optimise the efficiency of the system by operating the heat pump at a higherload, when it is most efficient, to charge the store and deplete it over several hours. To maximise efficiency and give N+1 redundancy, the heat pump will use the supply from two boreholes, and will be supported by 1MWp of renewable electricity supplied from ground and roof mounted solar PV arrays. To balance the power generated by the solar PV system and the CHP, and the thermal output of the heat pump and CHP, Veolia’s specialist energy team has developed a bespoke management solution which will manage the electrical and thermal balancing of the system using smart controls. The smart control strategy will optimise the overall system efficiency, and provide additional resilience to the site through carbon balancing of the energy delivered using the combination of the heat pump, CHP heat recovery, hot water boilers and thermal store.

The scheme includes high voltage andlow voltage electrical infrastructureupgrades to support the new plant andequipment with an extension of the site’sexisting HV ring main. Energy efficiencywill also be extended through the wideranging installation of LED light fittingsacross the buildings, and upgraded airhandling units.