Is there something unique to Italy that makes it an intractable problem? Where I live we've been able to shift a huge amount of our fossil fuels over to batteries in a relatively short time. It's nice that nuclear has power production 24/7 but it seems unnecessary when there's already a glut during the daytime
The fact that nuclear is good at the easy part of power production is not a point in favor of nuclear. Grids are built to peak needs; any grid that can handle peak load can handle base load.
"France's largest electricity producer said the move was required to comply with environmental regulations."
This is a policy decision, not a technical limitation. Palo Verde has been operating in the Arizona heat for forty years: nuclear can handle situations of low/high-temp water.
And no you’re not solving it with a buffer (batteries or any kind of other energy storage for that matter)