France's energy supply is 70% derived from nuclear power, exporting huge amounts of electricity to the UK. Their system is under immense pressure currently due to heatwaves, causing rivers to dry up and heating the water that is required for cooling. There are other problems being discovered, as the article mentions:

>...the recent discovery of stress-corrosion cracking in pipes located in the critical cooling systems of numerous French nuclear units. A dozen reactors have been shut down, and no one knows how long it will take to fix them. It may take years. Meanwhile, the heat wave and drought in Europe this summer have forced other units to go offline, since river water flow no longer suffices as an adequate coolant. Altogether, French nuclear capacity has been effectively cut in half.