Helena Rivers is a net zero lead for buildings and sites at consultancy Aecom
The National Infrastructure Commission’s (NIC) recent assessment of how infrastructure could support economic growth and tackle climate change made a bold statement. In essence, it recommended that the government should no longer pursue the deployment of hydrogen heating and that heat networks should be the preferred solution to help the built environment switch to low-carbon heating in 2050. The report provides clear guidance for the government that investment should be directed towards heat pump solutions.
“Heat networks are increasingly critical if we want to decarbonize our urban areas at scale”
The recommendation comes at a crucial time as the government relaxes the pace at which it aims to pursue net zero. Faced with a climate emergency, and with the combined energy used to heat the UK’s 30 million buildings contributing to almost a quarter of all the country’s emissions, I would say we need to act faster .
The desire to reduce our over-reliance on high-carbon fossil fuels throughout the built environment is leading to the exploration and implementation of a variety of low-carbon heating solutions, such as heat networks.
They are certainly not a new phenomenon; indeed, in the UK, the origins of district heating can be traced back to the 1960s, as a reliable method of heating that takes waste heat from coal-fired power stations. But deployment of the technology has since been limited to the UK, contributing to less than 3% of the country’s total heat generation.
Reheating an old idea
Heat networks supply heat from a central source and deliver it to various buildings via a network of underground pipes. The heat source could be anything: a dedicated boiler, an otherwise wasted heat source, a data center, sewers, even our rivers and canals.
One advantage is that they are scalable, with the potential to supply new buildings from the existing network over time, without the need to make major structural changes to the existing infrastructure. By providing low-carbon heat at scale, they can increase carbon savings and reduce air pollution, while creating jobs and facilitating building development.
Local authorities are now taking advantage of the grid heat proposal as a viable option to decarbonise their estates. Following a government zoning exercise, 200 UK cities have been identified to set up grid sources of heat to help power large, energy-intensive infrastructure. Projects have often involved significant reuse of existing heat systems in large public sector buildings such as hospitals and prisons.
The government’s Green Heat Network Fund is helping to accelerate this rollout, offering councils capital funding to put sinks in the ground and deploy new networks quickly. And in some areas, planning applications are strongly encouraging the use of heat networks in larger developments, which has led to a range of innovative projects.
Opportunity for contractors
Given the scale of the challenge, expert advice and support will be needed to enable a smooth transition. For the construction industry, this represents a significant opportunity to design and build large heat networks for the public sector and beyond. From civil works to install a network of underground pipes, to the adaptation of existing buildings and the construction of energy centers to transport heat from the source to the end user, the opportunity is significant.
However, as these are often inner-city projects, there is a high degree of public involvement and early stakeholder involvement is critical to ensure they do not cool off at the stage of design Collaboration between local authorities and contractors is necessary to build trust and confidence in these projects, which often take the better part of a decade from conception to completion.
There is also an educational factor. Heat networks are large projects with large scalability, so contractors and developers need to think long-term with their plans. Having a good master plan for a heat network project that takes into account the connectivity of future infrastructure development would ensure that this low carbon heating method reaches its full potential.
Heat networks are increasingly critical if we are to decarbonise our urban areas at scale, with major cities such as London, Bristol and Leeds adopting them. The NIC’s recommendations will support policy makers and industry to accelerate their deployment, as the built environment transitions to net zero.
