With 64,000 state school buildings in England alone, we can’t afford to waste time or resources on decarbonisation strategies that don’t work. Paul Cooper at Ridge busts some myths about lowering carbon emissions, and energy bills, in schools

Decarbonising the UK’s education estate will be essential for meeting our national commitment to reaching Net Zero by 2050. But the solutions to reduce carbon emissions could also translate into lower running costs for schools, and protect against rising energy prices.

With 64,000 state school buildings in England alone, we can’t afford to waste time or resources on decarbonisation strategies that don’t work.

At Ridge, we are among the industry leaders in low-carbon schools, and we’re now handing over the first Net Zero buildings. As a former post-occupancy assessor for the DfE, I also know that Net Zero is not just a financial and technical challenge, it’s a human one. We will need to upskill the industry, and school leaders themselves, to understand sustainable buildings that may work differently to the ones they’re used to. And we need to overcome common misconceptions about what works – and, perhaps more importantly, what doesn’t.

Here are five myths about Net Zero schools, and some simple rules to help clarify projects and make limited resources go as far as possible.

 

Myth #1: To achieve Net Zero, we need to add more thermal insulation

Traditionally, when we talk about low-energy buildings, we talk about thermal insulation and airtightness. Insulation is very important – but current standards are so high that we’ve already achieved all the easy wins. Adding further insulation, or upgrading from double to triple-glazing, might only reap marginal gains in thermal performance at the expense of much higher embodied carbon.

Adding further insulation, or upgrading from double to triple-glazing, might only reap marginal gains in thermal performance at the expense of much higher embodied carbon.

Instead, the most important first step is look at where energy is actually going within a school. Heating is typically responsible for only 15% of energy consumption in a new school building, because demand has been minimised using insulation, and the heating season for a school is relatively short. Find out where the rest is going, and you stand to make a much bigger impact.

 

Myth #2: Achieving Net Zero is about the design of a building, not how it’s operated

We can design a building to be Net Zero, but it will only perform as intended if it is operated in a Net Zero way. That can be counter-intuitive when we are used to throwing open a window as soon as we’re hot – when it’s hotter outside, we should be trying to trap the cool inside, not allow the heat in.

As the first generation of Net Zero schools is handed over, there will be a skills gap and inevitably some culture shock. But we can make it easier for users: for example, the controllers we install will tell you when it’s the right time to open a window, based on the inside and outside temperatures and the rate of change. We work with facilities managers to help them understand their new building, and to get it running as it should.

But we can make it easier for users: for example, the controllers we install will tell you when it’s the right time to open a window, based on the inside and outside temperatures and the rate of change.

 

Myth #3: ICT equipment doesn’t matter

As much as 60% of a school’s electricity consumption is generated outside of the school day. Server rooms are a major culprit – the equipment may only run at 3 or 4kW, but when it’s on 24 hours a day, 365 days of the year, it can be bigger than the total heating demand.

Even idling IT equipment consumes a small amount of energy, and when you multiply that across a school or a multi-academy trust, the impact is huge – under DfE benchmarking, small power appliances account for about 38% of total consumption. Encouraging staff and students to turn off computers and unplug chargers could make a significant dent in both carbon emissions and the annual bill.

 

Myth #4: Waste heat is a problem

In the UK, we’ve been fortunate to have a plentiful supply of cheap gas, so energy efficiency has not always been front of mind. That will no longer be possible in a Net Zero world, and it throws up some interesting opportunities. For example, in our Net Zero design for Bournemouth and Poole College, we captured the waste heat from the e-sports gaming rooms to produce hot water for washing up in its seven commercial-grade kitchens.

That’s not technically difficult to do, it’s just a case of thinking differently – instead of expelling the heat from ICT equipment straight outside, we treated it as a resource and looked at what else we could do with it.

Instead of expelling the heat from ICT equipment straight outside, we treated it as a resource and looked at what else we could do with it.

 

Myth #5: A heat pump won’t work in an older building

There’s a preconception that you can only use a heat pump if you’ve already achieved high levels of thermal insulation. That’s not true: one kilowatt of heat from a heat pump is exactly the same as one kilowatt from a gas boiler. The reason insulation is more important with electric heating systems is that it will cost a lot more to heat an inefficient building, because electricity is more expensive than gas, at least for now.

There’s a preconception that you can only use a heat pump if you’ve already achieved high levels of thermal insulation. That’s not true: one kilowatt of heat from a heat pump is exactly the same as one kilowatt from a gas boiler.

The other reason for this myth is that heating systems in older buildings traditionally operated at 70-80°C, and heat pumps have a technological sweet spot at lower temperatures – they are most efficient at about 50°C. But the newest models can run at much higher temperatures without problem. There will be an operating penalty, but it’s still better for the planet because it’s powered by potentially renewable electricity, rather than burning fossil fuels.

Net Zero is undeniably a major challenge for the education sector, but the good news is that we already know much about what’s needed. By sharing what we’ve learned from many low-carbon projects, in this sector and beyond, we hope that we can help schools to embrace a greener future, and reap all the benefits of more efficient, better performing buildings.

 

Paul leads the Building Services team for Ridge in Cambridge. He has a particular passion for projects which add social value, particularly those in the Education Sector, where he has delivered over 60 new school buildings. His focus is on producing more sustainable buildings while increasing partnerships between design teams and other professionals.

Paul and a team from Ridge will be attending the Education Estates event 15 – 16 October in Manchester Central on Stand 235 (next to the SEND stage) and would love to connect with any attendees.

Find out more about how Ridge helps schools decarbonise their estates by contacting Paul at paulcooper@ridge.co.uk

Contact any of the team in advance of the Education Estates Conference:

Paul Cooper
Alice Parker
Nathalie Richardson
Chris Rogers
Phil Kelly