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The power capacity over there is limited anyway (and DC besides), but the plants are on the rivers and with a drought and higher temps, there's less water and it's hotter. The article explains that the nuclear plants use river water to cool the reactors.

Well, the power over there is AC, actually. Generally 50 cycle AC as opposed to 60 that we use here. Their florescent lights flicker a little more than ours. :)

Anyway, the cooling issue is important, as you say - the steam, once its given up most of its thermal and mechanical energy in the turbine needs to be condensed back into water to be pumped back into the boiler (or reactor in the nukes), but the cooling isn't as effective when the cooling water is warmer (and especially when there's less of it). Many coal and nuke generators are de-rated in the hotter months, as are turbine engines which rely on cooler, denser intake air for their combustion. I've seen reductions of 10-15% on some generators. France's system, A/C load notwithstanding, wasn't built with 100 degrees in mind.

I read somewhere a day or two ago that the plants were limited to cooling water discharge of 25C for environmental reasons but that some plants were now running 29-30C with waivers. The environmental types were demanding that the plants shut down, rather than exceed the 25C limit.

Also read that the outside of the containment vessel was another limiting factor, with a "not to exceed" 50C rating and some plants were in the 49C range and that the plant operators were spraying the outside of the containment vessels with water from fire hoses.

I've spend a lot of time in Europe in hot summers and once those masonary building heat up, it's miserable to sleep.

Jack

the steam,...needs to be condensed back into water...

Had a boss years ago the did a stint with The Foxboro Company. He explained that it was all but water coming out
of a turbine, since the condesation reduced the gas volume, and thereby created a vacuum effect also contributing to
mechanical energy transfer, hence, high efficiency.

Or that's the way I remember it, some 20-odd years ago.

Generally 50 cycle AC...

Ah yes, the adjustment label on belt drive turntables if in Canada...(IIRC - also 20+ years)