https://ourworldindata.org/grapher/solar-electricity-per-cap...

The only other even slightly comparable country is Spain and they don't start until 2006/7.

https://en.wikipedia.org/wiki/German_Renewable_Energy_Source... where the laws that kick-started that. Under a SPD-Greens government - it wouldn't have happened with the conservatives or (market) liberals, that's clear.