UK: Ciat heat pumps are being used in a £5m project in several schools in Yorkshire being funded under the government’s Public Sector Decarbonisation Scheme (PSDS).
Abbey Multi-Academy Trust (Abbey MAT) is installing 38 AquaCiat TD300 air-source heat pumps in five schools. The project is anticipated to reduce carbon emissions by more than 9,000 tonnes over the lifetime of the scheme and save around £84,000 a year in energy costs.
The scheme uses renewable electricity generated by solar photovoltaic arrays installed on school buildings, which partly power the Ciat heat pumps and help further reduce operating costs and carbon emissions.
During the summer, when the school is closed and energy use significantly lower, electricity produced by the PV arrays will be fed into the grid, producing an income for the Trust and helping to cover energy costs for the rest of the year.
The new equipment will replace the need for high carbon-emitting gas boilers in the majority of the school buildings.
“We are collaborating with our project partners, consultant Energy Management Group (EMG), Robert Whetham Associates, HVAC specialist BReng Hull, and equipment supplier Cool Designs, in an ongoing process to develop the best possible outcome for our schools and the environment,” said David Ryder, head of IT and infrastructure at Abbey MAT.
Due to an impending funding deadline, Abbey MAT’s grant application for the scheme to Salix Finance (which administers the PSDS on behalf of the UK government) required submission of detailed proposals for each school within a tight window of just two weeks. The Trust worked closely with decarbonisation specialist EMG to prepare the application.
Working against the clock, one of the key challenges was to assess the requirements for upgrading existing radiators, to take account of the lower water temperatures delivered by the heat pumps. Detailed room-by-room surveys were carried out by Rob Smelt, director of BReng Hull, in collaboration with EMG and Toshiba Carrier distributor Cool Designs on the technical aspects of the grant submission.
The audit took account of the type and size of existing heat emitters, glazing, building fabric, room orientation, insulation and occupancy levels. It resulted in around 50% of existing radiators being replaced with higher capacity units, or augmented with new units to achieve the required heating capacity.
The additional investment required was covered by the successful PSDS grant.
Fine-tuning of the systems at schools converted to date has already begun, with an initial water temperature of 65ºC in the early morning reduced to 50ºC once students are on site and in class, taking account of the circa 3KW of heat they contribute within the average classroom.
The Trust is developing an innovative school-wide heat map, produced using temperature data from new heat-sensitive fire alarm systems. “The idea is to give a real-time overview of actual conditions in each space across a school, so that set-points and flow-rates from the heat pumps can be further optimised,” said David Ryder.