We have a Nuclear power station 30km down the road and 70% of French power is Nuclear. Now they have it all back to operational we don't get any of this silly "power balancing" stuff.
My Uncle finally had his 5kw/h solar panels and a 5kw battery storage device fitted. Even on a dull day he was running the place plus pushing power into his battery. He is going for another 5kw in panels. Said they were the cheapest part of it.
That being said, he doesn't expect to ever get his money back. He's too old.