France takes three nuclear reactors offline and limits eight others as river temperatures spike during third heatwave of 2026
Three nuclear reactors have been taken offline and eight more are running at reduced capacity as France's third heatwave in two months pushes river temperatures beyond environmental limits.
Reactors down across three rivers
Operator EDF confirmed on Sunday that reactor 2 at Golfech on the Garonne, reactor 3 at Bugey on the Rhône, and reactor 2 at Chooz on the Meuse have been taken offline. A further eight units are running with restricted output: reactors 1 and 2 at Saint-Alban, 1 and 3 at Blayais, 4 and 5 at Bugey, reactor 1 at Chooz, and reactor 3 at Tricastin. The Tricastin unit was throttled during the day but returned to normal operation by late afternoon, EDF told AFP.
Due to the climatic conditions and to respect the regulations on discharges, and therefore on the environment, the reactors: number 2 in Golfech, number 3 in Bugey and number 2 in Chooz are shut down.
In all, 11 of the country’s 57 reactors are affected, trimming output from a fleet that supplies roughly 70% of French electricity.
- Golfech 2
- Shutdown
- Bugey 3
- Shutdown
- Chooz 2
- Shutdown
- Saint-Alban 1
- Restriction
- Saint-Alban 2
- Restriction
- Blayais 1
- Restriction
- Blayais 3
- Restriction
- Bugey 4
- Restriction
- Bugey 5
- Restriction
- Chooz 1
- Restriction
- Tricastin 3
- Restriction (returned to normal late afternoon)
Why the river matters
Every French nuclear plant sits beside a river or the sea, drawing water to cool its reactors. In a heatwave, that water enters the intake warmer and leaves the discharge channel even hotter. To protect ecosystems, the nuclear safety authority ASNR sets maximum discharge temperatures for each site. When river temperatures rise, EDF must reduce power or halt a unit entirely to stay within those limits. The same pattern forced shutdowns during the second heatwave in June.
The third wave in two months
Météo France has now placed more than a third of the country under a red heatwave alert, up from 24 départements on Saturday. Around 26 million residents are covered by the warnings. Forecasters expect high temperatures to persist until at least the middle of the coming week. The current hot spell is the third wave of extreme heat to hit France since the start of the year.
- Third heatwave hits France; three reactors shut down, eight restricted
- Second heatwave forced EDF reactor shutdowns
- High temperatures forecast to persist until at least mid-next week
Racing to keep the lights on
With eleven reactors offline or constrained, France’s grid operator faces a tighter supply margin just as air-conditioning demand peaks. All 57 reactors are river- or sea-cooled, leaving no quick fix when waterways overheat. The June shutdowns already exposed the fleet’s summer fragility; the July repeat suggests the pattern is deepening as heatwaves become more frequent.
Fires compound the pressure
Beyond the energy sector, high temperatures are fuelling wildfires. Interior Minister Laurent Nuñez said authorities estimate flames have destroyed a total of 25,000 hectares, an area twice the size of Paris.
The authorities estimate that the flames have destroyed a total of 25,000 hectares of land.
Firefighting resources are stretched across the worst-affected regions while the red alert remains in force for Monday, covering roughly 40% of the population.
