AI data centres can warm surrounding areas by up to 9.1°C

Data centres built to power AIs produce so much heat that they can raise the surface temperature of the land around them by several degrees – creating so-called data centre heat islands that may already be affecting up to 340 million people.

The number of data centres built around the world is forecast to rise enormously. JLL, a real estate company, estimates that data centre capacity will double between 2025 and 2030 – with AI expected to account for half that demand.

Andrea Marinoni at the University of Cambridge, UK, and his colleagues saw that the amount of energy needed to run a data centre had been steadily increasing of late and was likely to “explode” in the coming years, so wanted to quantify the impact.

The researchers took satellite measurements of land surface temperatures over the past 20 years and cross-referenced them against the geographical coordinates of more than 8400 AI data centres. Recognising that surface temperature could be affected by other factors, the researchers chose to focus their investigation on data centres located away from densely populated areas.

They discovered that land surface temperatures increased by an average of 2°C (3.6°F) in the months after an AI data centre started operations. In the most extreme cases, the increase in temperature was 9.1°C (16.4°F).

The effect wasn’t limited to the immediate surroundings of the data centres: the team found increased temperatures up to 10 kilometres away. Seven kilometres away, there was only a 30 per cent reduction in the intensity.

“The results we had were quite surprising,” says Marinoni. “This could become a huge problem.”

Using population data, the researchers estimate that more than 340 million people live within 10 kilometres of data centres, so live in a place that is warmer than it would be if the data centre hadn’t been built there. Marinoni says that areas including the Bajío region in Mexico and the Aragon province in Spain saw a 2°C (3.6°F) temperature increase in the 20 years between 2004 and 2024 that couldn’t otherwise be explained.

Chris Preist at the University of Bristol, UK, says the results may be more nuanced than they first appear. “It would be worth doing follow-up research to understand to what extent it’s the heat generated from computation versus the heat generated from the building itself,” he says, suggesting that the building being heated by sunlight may be part of the effect.

Either way, the data centre is still increasing the ground temperature, says Marinoni. “The message I would like to convey is to be careful about designing and developing data centres.”