Heat networks should go beyond just heating

UK: Ahead of the rollout of the UK government’s heat network zones, Alfa Laval has highlighted the necessity for district cooling in a more balanced energy infrastructure.

In light of the current rollout only legislating for district heating, Neil Parry, Alfa Laval’s global head of district energy, has highlighted the necessity for district cooling, and how this can create a national district energy infrastructure.

The initial rollout of DESNZ’s zoning programme began with the identification of 28 pilot locations where heat networks are likely to grow or be built out in the future. Following this, six areas across the UK – Bristol, Leeds, Plymouth, Sheffield, Stockport, and two London sites – are set to be the beneficiaries of £5.8m in shared government funding in order to help establish the zoning model, with construction set to commence in 2026.  A total of 21 zoning maps have now been published.

As part of the scheme, it is expected that district heating will be the lowest cost of energy within each zone, with the wider goal of growing total demand from 3% in 2024 to 20% by 2050.

 “The UK is experiencing increasing temperatures due to climate change. By 2050, we will have just as much need for district cooling as we do for district heating, which is why it would be a critical misstep if the ongoing rollout was only limited to the latter,” he said.

“Beyond this, the integration of both technologies together is also fundamental to the concept of district energy, which will be critical to tapping into the nation’s waste energy potential and forging a credible path to net zero.”

According to Parry, two thirds of the heat required to heat and cool buildings in the UK is currently wasted. Without change, this figure is set to rise to four fifths by 2050, he insists.

“The network itself can act as a thermal store – capturing excess heat, such as that from a data centre or industrial processes, and then delivering it as required to the connected buildings. The heat in the network can also be used to produce cooling, via an absorption heat pump, for example, and therefore the energy in both the heating and cooling networks balance themselves, based upon the connected buildings’ demand. If we captured our current waste heat in this manner, we would be able to reduce the heating demand for buildings by 66% overnight.”

Parry maintains that district energy also facilitates the integration of a variety of renewable energy sources like wind and solar and can indirectly help to balance the electrical grid. 

“When the sun isn’t shining, or the wind isn’t blowing, the price increases – the district energy companies can then operate their thermal and electrical sources, sending thermal energy into the heating grid and electrical energy into the electric grid. This balances the electrical supply while also opening up an additional revenue stream.”

“This increases electric network resilience and helps to stabilise price levels minimising some of the well-documented challenges of renewable electricity production and large-scale electrification. In addition, ORC plants can also produce electricity from the thermal energy in the district systems, further increasing electrical output and stability”

While the long-term potential for heat networks is evident, Parry believes that the technology is currently being held back by a reputation of poor implementation in the UK. Just last year, Utility Week revealed that a third of heat networks in the UK are expected to be scrapped ahead of the introduction of new technical standards.

In response to this challenge, Alfa Laval is currently offering free, CIBSE-accredited district energy CPDs. 

 “If heat networks are going to succeed in the UK, education and training will be key to achieving reliable, efficient systems while also dispelling the major misconceptions that still surround this technology.

“As an energy source-agnostic technology, district energy and heat networks will be the key facilitators to a low carbon energy future. At this stage, the focus has to be on getting the pipes in the ground.”