EDF Shuts 2 French Reactors as 43C Heatwave Lifts River Temperatures
Updated
Updated · Euronews · Jun 25
EDF Shuts 2 French Reactors as 43C Heatwave Lifts River Temperatures
3 articles · Updated · Euronews · Jun 25
Summary
Two EDF reactors went offline Thursday at Nogent-sur-Seine and Bugey after river temperatures on the Seine and Rhone rose toward legal discharge limits; a Golfech reactor had already been shut Monday.
Environmental rules forced the cuts because nuclear plants return warmer cooling water to rivers, and EDF must curb output when heatwave-warmed waterways risk harming aquatic ecosystems.
RTE said France still has enough generation capacity despite reduced output across several sites in EDF's 57-reactor fleet, which supplied nearly 70% of national electricity last year.
The shutdowns come as France's heatwave has caused at least 18 deaths, put more than half of its 96 departments on red alert, and set a June 23 heat record dating to 1947.
Europe's third heatwave of 2026 is spreading across Germany, Spain, Portugal and Switzerland, with forecasters warning Mediterranean temperatures could reach 43C and power demand and prices could surge again.
France’s nuclear fleet is buckling under the heat. How will this impact the UK's energy security and electricity prices this summer?
As France bets billions on new reactors, are its nuclear ambitions on a collision course with the reality of a warming climate?
Beyond shutdowns, how are jellyfish blooms and warming rivers threatening Europe's critical energy infrastructure?
France’s Nuclear Power Under Pressure: Record June 2026 Heatwave Forces Major Reactor Shutdowns and Grid Adaptation
Overview
In June 2026, France faced its hottest day on record, with average temperatures reaching 30°C across 30 weather stations. This unprecedented heatwave was more widespread than any before, leading to over three-quarters of the country being placed under a red weather alert. The extreme heat put immediate pressure on France’s nuclear reactors, which are vital for electricity supply but rely on river water for cooling. As river temperatures rose, several reactors had to reduce output or shut down to comply with environmental regulations, highlighting the growing challenges climate change poses to energy infrastructure and national power security.