When we talk about data centres, we usually talk about electricity: how much they use and how demand for AI and cloud services is increasing the pressure on the grid.
But there is another side to the story. Data centres also produce heat, much of which is released into the air.
Could that heat help warm nearby buildings?
That is the opportunity behind heat networks. These shared systems carry heat from a central source to buildings such as homes, hospitals, universities and offices. A data centre could supply some of that heat while continuing to provide the digital services on which businesses rely.
The idea is attracting greater attention as England develops heat network zoning. Under the Energy Act 2023, the government has powers to identify areas where networks are expected to offer a cost-effective, low-carbon way to heat buildings.
It expects zoning regulations to go live later in 2026, with support for at least ten large towns and cities to establish zones soon afterwards.
For data centre developers, that could change an early planning question. Alongside access to power and suitable land, they may need to ask: who nearby could use the heat?
Making the connection is easier said than done. Heat is most useful when there is demand reasonably close to its source. The heat leaving a data centre may also need a heat pump to raise its temperature before a network can distribute it. Pipes cost money, and operators, network providers, councils and building owners need agreements that work over many years.
Timing matters too. A data centre might open well before neighbouring homes or commercial buildings are ready to receive heat. If each development is planned separately, the chance to connect them could disappear.
Heat zoning offers a way to spot those opportunities earlier. By mapping where demand is likely to grow, it can help developers and local authorities consider shared infrastructure while plans are still taking shape.
This will not make every data centre a practical heat supplier. Location, cost and future demand will determine whether an individual project works. But where the conditions are right, capturing heat could give a local community a useful benefit from the growth of digital infrastructure.
As the UK builds more data centres, their heat deserves a place in the conversation from the start.
Bryony Evans is an Intermediate Environmental Consultant at building services and environmental consultancy chapmanbdsp.
Years ago District Heating was held up as a model method of using industrial waste heat to provide heating for neighbouring homes. Let's hope data centres can re-activate this idea.
