Heatwave cuts power to 46,000 French homes, exposing grid risks
Tens of thousands of French homes lost electricity as extreme heat strained ageing underground cables, highlighting a continent-wide infrastructure vulnerability that will take decades and billions of euros to fix.
Around 46,000 households in France were without electricity on Friday morning as an exceptional heatwave pushed underground temperatures to levels that damage the power network. The outages, reported by grid operator Enedis, were heavily concentrated in the Île de France region and the southwest. Yvelines, located west of Paris, accounted for 25,000 of the cuts.
An additional 7,500 homes lost power in Gironde, while 3,000 were affected in Hauts-de-Seine. The disruption followed a larger outage on Wednesday evening that cut power to 68,000 homes in north-west France, though those supplies have since been restored.
"The number of incidents on the network continues to increase due to the ongoing exceptional heatwave. The situation remains in progress," Enedis said in a statement. The company's technical director had warned at a press conference on Monday that blackouts were highly likely.
Extreme heat causes the ground surrounding infrastructure to overheat, severely degrading underground cables. During a heatwave, underground temperatures can exceed 80C. In one stark example on Thursday evening, an electrical transformer in the Minimes district of La Rochelle overheated and exploded at around 7pm.
That incident cut power to nearly 10,000 residents before grid operators Enedis and RTE partially restored supplies after a two-hour intervention. The physical vulnerability of these systems highlights a major long-term challenge for European infrastructure investment.
France is currently running a programme to replace older underground cables with newer, heat-resistant models. However, roughly 15,000 kilometres of cable still require replacement. The upgrade programme costs around €1.5 billion annually, and at the current pace of investment, the work will not be finished until 2050.
This slow timeline has broader implications for the continent. France is not alone in facing this problem, as engineers have warned that large parts of Europe and North America remain highly exposed to heat-related power outages due to ageing electricity networks.
To manage the immediate crisis, Enedis has mobilised more than 1,000 technicians from the company and its partner firms. The operator has also activated its FIRE force, a specialist rapid intervention unit typically reserved exclusively for major disruptions, to restore power as quickly as possible.
