As the government targets Net Zero 2050 and accelerates national progress to a renewable energy future, reducing the public sector’s carbon footprint is critical.
The Public Sector Decarbonisation Scheme (PSDS) launched in 2020 to help tackle this challenge with financial support. It provides funding for projects that cut carbon emissions from public sector buildings with a target of 75% by 2037 (against a 2017 baseline).
Education is the public sector’s largest emitter of carbon from its buildings, according to the National Audit Office (NAO). It accounts for 37% of public sector emissions – 13% from primary schools; 11% from state secondary schools and 13% from universities.
The NAO notes that, while the Department for Education (DfE) is driving sustainable design of new schools, these will only represent 2% of the whole educational estate when delivered.
So, as with the wider built environment, upgrading existing educational building stock will be the key to achieving carbon reductions in line with net zero 2050 ambitions.
One of the most popular approaches has been replacing gas with modern heat pumps
Mike Egan Business Development Manager
Decarbonising heating
The PSDS has been successful in providing grants to schools - figures for Phase 3 of the PSDS show that 28% of funding was allocated to educational establishments. One of the most popular approaches has been to update school heating systems by replacing old gas or oil boilers with modern energy efficient heat pumps.
In fact, air source heat pumps were the most common technology applied under the scheme, though grants can cover other aspects of decarbonisation projects such as air source heat pump installation with improved building fabric installation and solar PVs.
Mitsubishi Electric has helped several schools using PSDS funding, working closely with clients to ensure they select the optimum solutions for their needs. One of these was St Andrews School in Chedworth, which received a £120,000 grant to replace gas boilers with Mitsubishi Electric Ecodan air source heat pumps as well as PV panels and improved insulation. The project saved 15 tonnes of CO2 per year and delivered annual energy savings of £4,000.
Changing criteria
In September 2024, the Department for Energy Security and Net Zero (DESNZ) confirmed the continuation of the PSDS supporting more public buildings including schools to switch to cleaner heating and cut their emissions, “accelerating to Net Zero”.
While the scheme retains its central mission, grants which were previously awarded on a first-come-first-served basis will now be allocated according to the potential carbon savings for a project.
This is an important point. A single technology solution won’t be the right answer for every school building, instead designers and installers must consider a ‘whole building’ approach to reduce long-term heating needs and electrical demands while removing fossil-fuel heating systems from the school estate.
This means that projects should focus on long-term carbon reduction results, which includes improving building energy efficiency. While heat pumps contribute significantly to this, it’s important to bear in mind other options such as mechanical ventilation with heat recovery (MVHR) for example.
Indoor comfort
Mitsubishi Electric’s Lossnay MVHR ejects stale air from spaces and re-uses the heat from this air to raise the temperature of incoming outdoor air.
This can provide a useful boost to indoor air quality for classrooms and other spaces, while avoiding uncomfortable drafts. It’s a good option for schools near busy roads where opening windows might not be a welcome option due to pollution and noise.
Another important consideration for today’s schools is removing excess heat from ICT labs and on-site server rooms. These are increasingly common as schools adopt more technology-based teaching methods, but the teaching spaces can be uncomfortably hot in the summer months.
Heat pumps can be used for cooling, but energy efficient VRF systems may also be an option depending on the project requirements. And, as VRF can also provide heating in cooler months, they can help to reduce the need for gas boilers on-site, reducing the overall carbon emissions further.
Figures vary, but The Times Educational Supplement puts the number of schools in the UK at around 30,000. That’s a substantial estate, with buildings of widely varying ages and conditions. To meet the challenge of decarbonisation, designers and installers must have a range of solutions to hand.
Mitsubishi Electric has developed solutions to meet these needs, and products that lead the field in energy performance. With our experience in education projects of all sizes, our team on in-house experts is ready to provide advice to help our schools prepare for the low-carbon future.
Mike Egan is Business Development Manager
