until renewable energy in Germany beats lignite coal as the largest source of electricity, says expert Norbert Allnoch, according to this article at Welt (in German). Thanks to this tweet by ekoplitan for the link.
This year, lignite coal will barely hang on to the top spot.
But that will be the last such year. The goal of 35% renewable in 2020 is sure to be reached. The only question is how many years before 2020 that will happen.