SPECIAL FEATURES HEAT NETWORKS/ HEAT PUMPS/ HEALTHCARE This month: Hybrid heat pump systems, HIU testing, waste heat, positive-energy homes University swaps gas boilers for propane heat pumps Northumbria University project replaces two gas boilers Northumbria University has replaced two gas boilers with propane (R290) air source heat pumps (ASHPs) in two buildings, as part of its decarbonisation programme. The ASHPs have been installed at the Newcastle Business School, Northumbria Law School, and Northumbria School of Design, and will heat lecture theatres, offices and cafes. In a project managed by Equans, two 150kW and three 200kW R290 ASHPs were designed, made and installed by UK-based Clade Engineering Systems. The installation was officially switched on by the university in May. R290 is a natural refrigerant with a very low global warming potential of three. Although flammable, propane is cheap, available and performs very well, with high coefficients of performance at 60C flow temperature. Operating at this temperature, a seasonal coefficient of performance of more than 3.0 is expected. The hazards of using a flammable refrigerant must be considered as part of the design risk assessment, and measures taken to reduce risk. The heat pump units installed at the university all have automatic leak detection, and the housing is ventilated. Service personnel accessing or working on the heat pumps must have the appropriate competencies. The heat pumps are on the existing rooftop plant areas. The free air space for harvesting heat, and proximity to the plantrooms, make for an efficient system. Rooftop placement also contributes to noise and safety management. Clade had to upgrade electrical cables from the incoming supply to provide power to the heat pumps, a common, yet important, procedure in large heat pump installations. Mechanically, the heating systems needed new pumps, control valves, and control strategies. The old boilers were retained to supply extra heating in the extreme cold conditions sometimes experienced in Newcastle. Clade s aftercare team will regularly clean the evaporators to maintain efficiency. Data, gathered remotely, will also be used to improve performance. Government reveals 2m funding for 11 trial projects As part of its Heat Pump Ready Programme, the government has announced funding for 11 projects across England and Wales. The programme aims to install 600,000 heat pumps annually by 2028, as part of the Department for Business, Energy and Industrial Strategy s 1bn Net Zero Innovation Portfolio. Stream 1 investigates solutions and the trial of methods for heat pump deployment, and Phase 1 of the programme will provide funding of more than 2m. The full list of projects are: Heat Pump Ready Newcastle; Utilita Energy Heat Pump Ready Programme, Sunderland; Renewable Heat Infrastructure Network Operating System (RHINOS), Leeds; Clean Heat Streets, Oxford; Greenwich Thermal Infrastructure Motivating Electrification (Greenwich TIME); Bristol Heat Pump Ready; Project Gaia, Teignbridge; PACE Financing for Heat Pumps in Rural Cambridgeshire; SAPPHIRE Solo, Blairgowrie; Prosumer Model for Heat Pump Deployment in Cherwell; and Heat Pump Ready Bridgend. Ground source specialist Kensa Group is working with local authorities and energy companies on the projects in Leeds, Greenwich, Teignbridge and Bridgend. Its sustainability director, Ieman Barmaki, said: We are trying to break down the perceived barriers to the widescale electrification of heat, and showcase to policymakers and the public that networked heat pumps can achieve mass decarbonisation goals at scale, for the lowest economic and societal cost. Danfoss FlatStations Tried & Trusted. www.sav-systems.com/danfoss-cibse SERIES HIU www.cibsejournal.com August 2022 27