Heatwaves expose Europe’s growing electricity challenge

Europe’s summer heat tested the electricity system from both directions: households used more power for cooling just as some major sources produced less. Western Europe recorded its hottest June-July period, with an average temperature of 21.62°C, 2.79°C above the norm, according to the EU’s Copernicus programme.

France’s grid operator RTE reported a 20% increase in electricity demand on the hottest days. Air-conditioning and cooling systems, once treated mainly as matters of comfort, are increasingly linked to public health and safety during extreme heat.

Nuclear generation fell by more than 5 gigawatts on average and by as much as 10 gigawatts during the most difficult periods. High water temperatures in rivers used to cool plants, including the Rhône and Danube, limited production. In Switzerland, reactors at the Beznau plant were slowed and then shut down on June 26 after the Aare reached 25°C.

Wind generation also suffered from what the commentary calls a “wind drought,” as insufficient winds kept turbines from operating at full capacity. Solar power reached record levels and partly offset the shortfall, but its output dropped close to zero around 8 p.m., when demand rose as households returned home. Flexible gas plants filled the gap, although gas-fired electricity costs more and can set the market price under the marginal pricing system.

The pressure is not expected to disappear with the summer. The European Commission says heatwaves are becoming more frequent, more intense and longer-lasting. The International Energy Agency expects EU electricity demand to rise by more than 50 terawatt-hours each year through 2030, driven in part by electric vehicles, green hydrogen, electric industrial furnaces and data centers.