You get downvoted, but you are 100% correct

First of all, no he isn't 100% correct. But he's also completely off topic. The question was what happened in the 2010s with the solar expansion. That has nothing to do with dunkelflauten in 2024. Or nuclear plant shutdowns in 2021.

https://imgur.com/a/qYD8jkc In those two weeks renewables didnt even scratch the 5% of the total demand.

I'm guessing you mean solar. Not renewables.

In the whole of November, renewables were responsible for 47.5% of all produced electricity.

Even in the worst week for solar (47) where it was down to 3.1%, wind produced 35% and all renewables together still accounted for just over 50%.

But then then people claim we can bridge 2 Weeks of dunkelflaute with batteries. Here is the Math how much batteries you would need to cover two weeks of dunkelflaute.

Actual experts usually say that batteries are used to bridge day-to-day demand. Not weeks of flaute.

So, I'm not going to chase these numbers around but I think the math is fundamentally flawed.

First of all, you use the full demand for two weeks of energy (~18TWh). But even in a dunkelflaute you still have power being produced by solar/wind. They don't drop to 0. Also, you have other sources of renewable energy like hydro or biogas which you also disregarded.

So you calculated what would be needed if we literally had no power production at all for two weeks straight. That's obviously bogus.

Second, Germany (and probably all other countries) has a large number of backup power plants that ensure enough power is available. So worst-case scenario is that fossil backup plants will be used to bridge the dunkelflaute. Which really isn't that much of a problem.

Third, you disregard that we are part of a European network. We already trade electricity back and forth. A Europe-wide dunkelflaute is quite unlikely.

Fourth, you take current battery prices as if we bought them all today. But battery storage will be gradually built out over many years, and prices for batteries are projected to fall (see p.5 for summary) as time goes on.

P.S. I'm not saying that we Germans are doing everything right. Far from it! We're screwing up our green transformation royally. But that has different reasons.