London’s data centres could heat 500,000 homes

Author: Joe Peck

According to a new report from global infrastructure company AECOM, London’s data centres are releasing enough waste heat to warm up to half a million homes each year, yet much of this potential energy is being lost to the atmosphere.

Commissioned by the Greater London Authority (GLA) and conducted in partnership with asset management and commercial consultants HermeticaBlack, the study reveals that up to 1.6 terawatt-hours of heat could be recovered each year from the capital’s data centre estate – equivalent to meeting all the heating and hot water needs for all homes in Ealing.

The report – Optimising Data Centres in London: Heat Reuse – identifies opportunities to adjust planning and infrastructure policy to unlock this potential for London and sets out recommendations including updated planning guidance, targeted infrastructure incentives, and a standardised framework for activating heat offtake from data centre operators.

This includes making sure the designs for all future data centres optimise the ability to re-use waste heat.

The potential of heat recovery

The uptake of heat recovery in London is currently limited, but AECOM’s report identified cities around the world, including Geneva, that are utilising as much as 95% of the heat recovered from a data centre.

The infrastructure consultant says that UK cities, including London, have an opportunity to heat new homes with clean, affordable energy. The report estimates, based on the quantum of heat being currently lost, there is the potential to heat up to half a million homes.

When this model was tested across London’s data centre dataset, it evidenced the network could provide enough heat to supply around 350,000 homes.

With more than one in eight London households in fuel poverty, and the UK still heavily reliant on gas boilers for home heating, the report highlights the social as well as environmental case for change.

Data centres – often located in densely populated parts of East and West London – offer a local, low-carbon source of heat for nearby homes, schools, and public buildings.

The added value of data centres

Data centres are critical to catering for the increasing demand for AI and high-performance computing. The computing power required generates higher server temperatures, creating higher-grade waste heat more viable for reuse.

Asad Kwaja, Associate Director, Sustainability & Decarbonisation Advisory at AECOM, says, “The UK needs complex digital infrastructure to enable its ambitions to become a leader in AI.

“Data centres lie at the heart of this conversation, but we must consider their wider use if they are going to play an integral part of the UK’s infrastructure landscape. Data centres should no longer be considered as just an energy consumer; they can become a part of the whole energy ecosystem.

“London is one of the biggest data centre hubs across Europe, the Middle East, and Africa, and hosts 80% of the UK’s capacity. With the right planning, coordination, and investment, London’s data centres could play a pivotal role in decarbonising the heat needed to power the influx of new homes the capital needs to build to address the housing crisis, while also cutting bills for existing residents and improving local energy resilience.”

A scheme to capture the waste heat from data centres is already underway in North West London.

In 2023, the Old Oak and Park Royal Development Corporation (OPDC) secured £36 million in funding from the government to deliver a heat network, developed by AECOM, to serve 95 gigawatt-hours annually, recovering heat from up to three data centres.