France already has bidirectional power lines to trade electricity with Spain.
They were used to rapidly restore power in northern Spain after the outage and that interconnection actually caused a very short blackout in southwestern France.
The infrastructure France thankfully refused to allow is fossil gas lines, saving Europe decades of gas usage to justify the investment.
While that is indeed not the most objective source, they are actually correct. Even if their stability argument didn’t hold water (it does), they should keep the nuclear plants active and upgrade transmission lines to export to Germany through France and displace coal plants in Germany’s electricity market… And literally save on radioactive waste which coal plants produce tons of.
What does “upgrade the grid” mean to you?
Digging tons of rock and salts to store energy with batteries?
In Europe there are very few remaining sites to build hydro power, and those have serious ecological consequences too… I don’t see to many alternatives. Biogas options are nearly tapped out. There is potential with geothermal using new digging techniques, but they’re mostly in the testing stage still.
How is using batteries better than using said rocks to power nuclear reactors?
There is a limit to how much one can add uncontrollable energy sources to a grid…
Yes, I only listed means to store or produce energy because upgrading powerlines won’t fix power fluctuations : that is due to imbalances between production and consumption, no amount of upgraded to transmission capacity is likely to help.
Load management might help, however. But it’s typically hard to get people to consume more when needed and power shedding is expensive on the electrical operator… Especially since those oscillations were unexpected. Also those things already exist in many European countries.