Optimising and Decarbonising University Heat Networks

Chris Davis, Head of Marketing at Hysopt, explains how digital technology and the new Government Heat Network Efficiency Scheme can help universities decarbonise heat and lower energy costs

The heat challenge for university campuses

Across the UK, Universities are committing to challenging carbon reduction targets, with decarbonisation of heat identified by many as a key challenge for the sector.

Meanwhile, according to the Association of University Directors of Estates (AUDE), in 2022, energy accounted for 18.5% of total property costs, amounting to £379m.

However since the global energy cost spike in 2021, many universities are expecting their energy expenditure to double when they exit their current forward purchase agreements.

Net zero carbon

Universities’ commitments to net zero require significant reduction in the consumption of gas, and investment in alternative low carbon heat sources such as heat pumps.

But figures from the AUDE’s “Decarbonising Heat Networks in University Estates” study revealed that half of university carbon emissions come from natural gas.

This makes the transition to low carbon heat difficult, especially when large gas boilers and combined heat and power systems serve multiple buildings through campus heat networks. While the university sector is making progress, many are still unsure how to handle high-carbon assets like CHP and whether heat pumps can efficiently heat older buildings.

Heat networks

University campuses, with their high population density and predictable high heat demand, are ideally placed to benefit from heat networks (otherwise known as district heating).  

Heat networks – which supply heat from a central source to heat multiple buildings connected by insulated underground pipework - form a key part of the UK’s transition to net zero emissions as they enable connection to larger-scale, renewable and recovered heat sources.

Performance gaps

Recent work by BEIS however has indicated that many existing heat networks operate inefficiently, leading to higher than expected energy costs, unnecessarily high carbon emissions, and generally poor thermal comfort levels in buildings.

Meanwhile, studies of over 400 heating installations – including university heat networks – reveal that these so-called “Performance Gaps” mean energy costs are, on average, 32% higher than they otherwise need to be, and carbon emissions 40% higher. Even in new and recently upgraded systems, significant opportunities to optimise performance are being missed.

The current increase in gas prices exacerbates the issue, leading to unnecessary and avoidable extra heating costs that can run into hundreds of thousands or even millions of pounds per year.

Using HVAC digital twins to address heat network performance gaps

Universities are increasingly discovering how alternative approaches using “HVAC system digital twin” technologies can help tackle optimisation of their campus heat networks.

This approach simulates the whole installation in a "virtual replica" to identify cost-effective solutions for eliminating performance gaps.

For example, the University of York used a digital twin to find out why heating distribution systems in buildings connected to their heat network were causing high energy costs due to excessive gas consumption.

Simulations from the digital twin showed how specific changes to the installation would reduce gas consumption by over 10 million kWh per year, heat that was otherwise being "dumped" by the CHP units.

As a result of eliminating this heat wastage and subsequently reducing the gas consumption of the backup boilers, the digital twin demonstrated energy cost reductions at 2021 price levels of £285,000 per year.  

Jump forward to todays “new world energy costs” with universities existing fixed price contracts, the unnecessary costs avoided would be closer to £1m per year.

Meanwhile fixing fundamental performance issues enables buildings and heat networks to operate under conditions suitable for low-carbon heat generation options such as heat pumps, both from an operational and capital investment cost perspective.

Heat Network Efficiency Scheme (HNES)

The newly formed Department for Energy Security and Net Zero hopes to address the performance issues of existing heat networks (including the buildings connected to them) through the new Heat Network Efficiency Scheme.

The £32m grant programme opened for applications in February 2023 and provides funding for public, private and third sector applicants in England and Wales, including universities and colleges.

Up to £2m of revenue grants are available, providing 100% funding for optimisation studies, for which HNES will typically fund up to £24,000 per project.  Studies including HVAC system digital twins align well with the requirements HNES revenue grants.

A further £30m is available as capital grants, providing 50% match funding for the delivery of eligible intervention/improvement measures.

Further details can be found in the Heat Network Efficiency Scheme Guidance for Applicants.

In summary

In conclusion, optimising and decarbonising university heat networks is essential to meet carbon reduction targets, lower energy costs and improve thermal comfort levels in buildings. The HNES scheme provides an opportunity for universities to trial HVAC digital twins to identify inefficiencies and the most viable solutions for improving their heat network performance.

To learn more about this alternative approach to reducing heat network performance gaps watch the recent Hysopt webinar “Making Public Buildings Low Carbon Heat Ready”