Professor Glew
Professor David Glew, Director of the Leeds Sustainability Institute, discusses why research is pivotal to the wider understanding and implementation of technologies which lower heat emissions in the home.
Tell us about the Leeds Sustainability Institute
The Leeds Sustainability Institute, known as the LSI, is at Leeds Beckett University. In the LSI we have three research themes: sustainable behaviour, sustainable buildings and sustainable urban environments.
What do these areas focus on?
Sustainable Behaviour is about understanding the struggle people face in trying to make choices which are conducive to net zero, such as the difficulty in convincing people to retrofit their houses. Within this we explore hydrogen conversion, heat pumps, sustainable transport and other options that people may need advice on.
The Sustainable Buildings strand tests questions such as: What are the best retrofits? How do the modelled versus measured retrofit performances match? What are the risks that you introduce into homes when you retrofit them?
As part of this we have developed a building performance evaluation test called the co-heating test which measures the overall energy efficiency of a building, and which is now used by others across the world as a benchmark test. We do all the other performance tests too, like thermography and air tightness testing.
Then, the final research theme, Sustainable Urban Environment, observes the community and the city. For instance looking at how green spaces in cities affect air quality and the urban heat island effect. We’ve got a network of sensors around Leeds, which we, and others can use to look at temperature and pollution hotspots in the city to help planners and building designers make better informed decisions.
Our research projects tend to come from a mix of funding from national government, local authorities, housing associations, product manufacturers and research councils.
We’re really finding that we’re getting more interest in our research than ever before and this seems to be happening all over the country, as national bodies that we are part of or work closely, with like the Building Performance Network, Good Homes Alliance and all-party parliamentary groups for Net zero and Healthy Homes are all seeing an increase in activity too.
So we are certainly kept busy!
What about local projects?
Our local networks are vital to our research, social housing providers help us find case studies for our research projects and in turn the directly benefit from our findings. As a University we take our role as an anchor institute seriously, and we are committed to help lead Leeds on its journey to being net zero and to achieve its ambition to be ‘the best city to live in’.
An example of our work with Leeds City Council is that we’ve recently joined the city’s low-carbon heat district network. For the council to go and dig up a road and provide heat to part of a city with a low-carbon source, is an expensive endeavour, and requires some guarantee that they will be able to sell a large chunk of that heat. We said we’ll commit to buying this heat, which means every other institute or company on this road doesn’t have to pay that infrastructure cost, and they can tap in to this renewable energy more cheaply, plus it reduces our carbon emissions at the same time, getting us off gas.
Tell us about your recent successes
One that is coming up is our big launch in June of a £3 million research project. This is funded by the Department for Energy and Security Net Zero (DESNZ), and is three years of work across three universities, which we led on. The project has helped us to understand better the assumptions that are put into energy models, which could be used to inform changes to them in future. For example, the EPC currently uses data which is deliberately ‘not real’ so that we can compare all houses with one another more fairly, which can be really confusing to people, who quite reasonably expect it to reflect their specific energy use. Our work on the project will help us figure out how that can be a better guess.
What future trends or policies do you think is going to have the biggest effect on the energy market?
The biggest thing is decarbonising heat. Heat has been ignored because it is incredibly difficult to tackle. The difference between heat and electricity is when you plot the UK’s gas consumption, starting in summer, you’ll find we use basically very little, mainly just to allow us to take showers and do the washing up. And then it gradually gets a bit bigger to October, and then it skyrockets over winter when we all turn on our heating, which we call peak heat. This looks like Mount Everest when you plot it and then it drops all the way back down again around springtime.
Electricity, on the other hand, just bubbles along like rolling countryside, no mountains in sight. This is a problem for the government who want to electrify heat, because of course you can make electricity from renewable sources. Eventually, if everyone’s on electricity, then simplistically that’s 100% green.
The problem is we can’t deliver Mount Everest with electricity. Even if we massively increased our electricity generation capacity (which would cost billions), we might only be able to deliver, say, Ben Nevis. We have to bring that peak heat right down. So that’s one of the key motivators for government to fund domestic retrofits. These reduce peak heat, and fundamentally if millions of homes are retrofitted, we could bring Mount Everest down to Ben Nevis, and then have a chance at electrifying heat.
Another help is, heat pumps, which deliver electrified heat more efficiently to homes. These use one unit of electricity to deliver two or three units of heat, which instantly makes Mount Everest two or three times smaller. But that’s still way too big, and that’s why we need to do domestic retrofits too.
There’s going to be a real barrier and a real transition, which may take decades, in installing these new technologies. We won’t necessarily know how to use, maintain and install them properly to begin with, and that’s just inevitable. You have to go through the learning curve, and at LSI we’re trying to make that as painless and seamless as possible for people.
Do you envision any future challenges for the energy sector, and if so, how do you feel they can be overcome?
I can’t think of anything else that would be as challenging as encouraging people to use heat pumps and to retrofit, even if the technological solutions are there. It’s so expensive, and there are risks that you might introduce through the process. It’s that unknown factor that people don’t want to even touch. There’s such a big push to try and make these changes something that people want and are happy to pay for themselves, but then there is also such a huge void between what we hope people will do and what they will actually do. Finding ways to sell the benefits beyond simple paybacks is essential. We are starting to find good evidence that the non financial benefits that these things can bring, like your home being warmer in winter, being damp free, having fresher air to breath and avoiding overheating in summer, are the real motivators for people to adopt these technologies and may be key to getting Mount Everest down.
What was Leeds Beckett’s involvement with the Demonstration of Energy Efficiency Potential (DEEP)?
We were the consortium lead, and our role was to fully retrofit, model and test the performance and risks of 14 solid walled homes. There are eight million of these homes in the UK, most are uninsulated and they’re more likely to have fuel poor people in them.
We were showing how these homes can be retrofitted in a low-risk and effective way. One of our major questions was do you need to insulate the walls or can you get houses to be good enough without having to do that conversion. It seems solid wall insulation is by far the single most important intervention for these homes in terms of reducing the risks of damp, reducing fuel bills and improving a home’s EPC score.
We were looking at what happens in the retrofit journey over 30 years of the home, where things get installed in piecemeal and contrasting this with what we call the whole house approach. It doesn’t mean retrofitting the whole house, it just means not leaving gaps between the different measures that you have installed, because this is when problems can creep in. So in these fourteen homes we deliberately left these gaps between different insulated parts of the homes and measured the risks and performance of the retrofit, then compared this to when the gaps were later filled in. We will be publishing the reports about those 14 case studies and the results from the rest of the project in June on the DESNZ website.
What do you think are the top knowledge gaps in relation to heat loss?
It was useful to identify what areas were important and what were less so. A lot of builders get put off when you interpret the standards as saying you have to remove all possible risks in homes caused by retrofits. This can add thousands to the cost of retrofitting a house. Instead a truly risk based approach to retrofit should be to balance risks, costs and benefits i.e., which bits are really essential for which homes. Guidance like this has the potential to be transformational. It means all of these homes whose retrofit options were previously unaffordable might now be retrofitted without excessive cost.
People were also confused as to how much benefit you can get without retrofitting solid walls. I sympathise, as it’s really hard to make that change. We were able to really do our best to work out if you can get to the government target of an EPC span C without insulating the walls. Fundamentally, it’s almost always a no. We’ve essentially been tweaking and tinkering around with policy for insulating solid walls but mostly retrofit policy supports affordable measures to be installed i.e., everything other than solid wall insulation. It may be a surprise to you that over a third of all retrofit measures is simply installing heating controls in homes. This is important, but it’s not in the same league as solid wall insulation. What our research is saying is you’ve got to focus on solid wall insulation to stand any chance of achieving your EPC or net zero targets, which I think is a pretty clear message and we’ve got the data to support it now.
What do you think is the best solution to counteracting heat loss?
Insulating your walls is always best as a rule of thumb, but beyond this it can varies building to building depending on shape, construction and how much insulation is already in the home. For instance, if you have a mid-terraced town house with large single glazed windows, you should look to at your windows. We were really impressed with secondary glazing, not just double glazing. If you can’t put double glazing on, secondary glazing made a really good reduction in heat loss.
Are there any particular concerns you have for how the UK will reach its net zero targets by 2050?
Heating homes will be the focus. You can decarbonise electricity, and the hope is you can electrify heat. But as we’ve discussed, getting Mount Everest down to Ben Nevis is a big challenge.
These difficulties are technically achievable. The government could dedicate £10 billion a year for 20 years to insulate our homes, and industry will gear up and deliver that, currently it is around £1-2 billion and only for a few years at a time, so we are an order of magnitude out on both the scale and duration of policy needed to fix the problem. Sadly, government hasn’t got a national retrofit strategy that gives certainty to the market and supply chains on appropriate time scales, i.e., several decades. Retrofit policy now is stop start so no one has a chance to make it affordable.
This leaves it to the market try to come up with a solution, but now, people don’t want to spend money on this. This is why a lot of our work is on understanding why we do and don’t make sustainable decisions as individuals and organisations.
We see the benefits beyond cost saving as very underexploited. People want safe, comfortable, healthy homes, which don’t need maintenance, and retrofit can achieve this. But these are not being used as the selling points.
It’s really all about the hearts and minds piece, and achieving social acceptability and it being normal to have a heat pump or solid wall insulation. In reality even a mix of market and policy led retrofits still requires transformational changes from the top, in previous years it would have been a bold politician to take that challenge on, however, the world has changed so much in recent years it doesn’t seem so farfetched anymore.
LSI’s Dr Kate Morland is talking in the elemental Housing Hub at InstallerSHOW 2023 on the panel: Who is going to buy heat pumps?
InstallerSHOW is 27-29 June at the NEC, Birmingham. Free registration is open now at www.installershow.com
