As AI data centres guzzle energy, can we harness their wasted heat?

The rapid growth of AI data centres is putting greater pressure on electricity grids and worsening the global energy crisis. Engineers in Denmark have found a way to reuse the heat generated by these facilities, which is usually released into the outside air. The International Energy Agency says data centres used 485 terawatt hours of electricity in 2024, or 1.5 percent of the world’s total supply, a share expected to reach 3 percent by 2030. Their expansion is also prompting protests, including against a new Microsoft data centre near Amsterdam.