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CUBO Winter Conference 2021: How we’re decarbonising hot water

1 December 2021

Ahead of the launch of our net-zero carbon pathway in December, James Tiernan – Head of Energy and Environment at Unite Students – shared some of our plans for decarbonising hot water at CUBO’s Winter Conference 2021.

We reflect on those plans, along with those raised on the wider panel discussion about sustainability.

Following November’s COP26 conference in Glasgow, there’s more focus on carbon and going net-zero than ever before. But given that students consider climate change to be the most urgent challenge facing society, sustainability has already been high on the Higher Education sector’s agenda over the past few years.

It’s not only universities that are taking this seriously: in March we announced our own commitment to become a net-zero carbon organisation in both our organisations and developments by 2030 as part of our sustainability strategy, developed in consultation with universities, suppliers and employees.

Last week, our Higher Education team attended the CUBO (College and University Business Officers) Winter Conference 2021. With the details of our net-zero pathway coming soon, James Tiernan – our Head of Energy and Environment – was on a panel called ‘Sustainability on Campus’ and shared details of just one aspect of our plans: decarbonising hot water in our buildings.


Decarbonising hot water at Unite Students: why and how?

Hot water is energy-intensive, comprising of about one-third of the overall energy consumption at some of our sites. Yet, as James noted, “that energy literally goes down the drain,” making it a major negative for calculating Energy Performance Certificate (EPC) ratings.

At present, we use hot water cylinders to provide students with hot water in a majority of our buildings. While they’re efficient they’re high-carbon, high waste, and make it a challenge for a building to get a high EPC rating. Additionally, we have to run these cylinders 24/7 to maintain supply for students and ensure water hygiene compliance.

James and his team have looked into several options to reduce the carbon output of our hot water supply. One is to refit the central heating system, but this is a very expensive option. Another is replacing the cylinders with point-of-use, on-demand water heaters, which reduce wastage – but these are also high-energy and may involve a lot of rewiring within our properties.

Finally, they looked at installing air-source heat pumps as a direct replacement for the cylinders. These use the same fittings as hot water cylinders, meaning they fit straight into the existing plumbing and there would be minimal disruption within the buildings.


Our initial findings

But do they work? To find out, we’ve undertaken desktop analysis with partners to establish what the impact of using these heat pumps will be on energy consumption, carbon emissions and EPC rating, as well as running a trial installation to test performance under likely usage conditions and compatibility with our existing systems.

The findings James shared so far make for encouraging reading. Air-source heat pumps will allow us to achieve an EPC rating of B in our buildings when used alongside measures such as LED lighting, solar panels and better controls in our buildings, and they achieve a coefficient of performance (COP) of 240%: this means that for each kilowatt hour of electricity used to run the pump, you get 2.4 kilowatt hours of heat output.

Most importantly, they look to offer significant carbon reductions through reduced energy use, reducing carbon by 15-18% per bed in our trials. As an added bonus, they also offer major cost savings, not to mention a lack of disruption that the other alternatives would come with. We anticipate that solutions like these will become more widespread in the coming years – not to mention more affordable – following the announcement of government grants for research and development.

We’re now planning to install the heat pumps at three of our sites as part of major refurbishment works in 2022. This is just one small aspect of our net-zero strategy, but it’s an exciting glimpse at how a like-for-like replacement can lead to substantial reductions to our carbon output, especially when scaled up across our 73,000 beds.


What we learned from the panel

The panel also included Fiona Goodwin, Director of Operations and Planning at the Environmental Association for Universities and Colleges (EAUC), and Peter Anstess, Head of Retail at the University of Sheffield. They too shared insights into their activity on sustainability – such a huge and broad topic that their own specific focuses for the discussion were very different.

We heard from Fiona about how EAUC had been busy supporting the sector in becoming more sustainable. Through their work setting up the Climate Commission for UK Higher and Further Education in partnership with GuildHE, Universities UK, and the Association of Colleges, they’ve helped to put together a climate action toolkit for the Higher Education sector; a further partnership with the Association of University Directors of Estates (AUDE) and sustainability consultants Arup has also delivered the Sustainability Leadership Scorecard to help universities and colleges to assess their sustainability performance.

Peter, meanwhile, shed some light on how the University of Sheffield is making its campus catering options more sustainable. This included upgrading their refrigeration to a more energy-efficient model, replacing beef on their menus with Quorn alternatives, and introducing a reusable cup and bowl scheme. Students can keep the items for up to 10 days free of charge, during which they can return them to collection points around campus. Where many retailers have introduced a discount for using a reusable cup, it works the other way at the University of Sheffield: 20p is added onto the cost of every single-use item bought.


Bringing students along on the journey

The panel agreed that educating and equipping students with sustainable behaviours was a challenge, with no silver bullet – but an important one. When asked about Unite Students’ approach, James said:

“If you sit students down and ask them if this is important, you get a resounding ‘Yes, this is important: it’s influencing the way we live our lives.’ But students are only human – we all know what we should do, but don’t always do it. So, we’re doing everything we can to educate, encourage, promote and provide conditions for them to live the right way.”

What that means at Unite is relaunching our Positive Impact scheme, based on the National Union of Students’ award-winning Green Impact scheme, as a broader sustainability engagement programme with education, competitions and challenges: a truly comprehensive approach, which is encouraging rather than punitive.

We’ll share more details about Positive Impact and our net-zero plans soon. In the meantime, you can catch James at Property Week’s Student Accommodation Conference 2021 on Wednesday 8th December, on a panel discussion titled ‘Smart thinking: how Covid-19 hit the innovation accelerator’.


James Tiernan was also a guest on our Accommodation Matters podcast episode on sustainability in Higher Education earlier this year – you can listen to the episode below:

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