[bpfrh]

sorry my bad for formulating it badly: less solar and now wind means days or even weeks with no solar and no wind aka "dunkelflaute"

In germany a week long dukelflaute occurs every 2 years.

You don't need 30% more panels, you need to store energy for the all usage for about a week.

[marcosdumay]

Oh, you mean a rare eventuality.

Yes, you need some redundant power supply. We should probably be investing more on research about synthetic fuels than we are right now (and shelf-stable flow batteries; hydrogen won't cut it in a micro-scale, even though it's great for national grids), but for a long time everybody will still use fossil fuels for that.

It's not a huge problem right now.