Oh come on, you make up new limits and constraints each time on each response.. You can run the world solely on renewables given enough effort and time, is a similar ridiculous counter to you now bringing up 2030..... pathetic really.

Building new nuclear plants, or just recertifying the old ones accordingly to current standards and supplying them with enough fuel would have been possible til 2030, right?

Again, Frauenhofer is a diverse large body with multiple branches, they have also studies about cost and way to Germany on fully renewables 2050, without 100% gas backup - which study are you citing please?