One major problem a non-sunny, non-constant-storm and non-wast-ranges-of-mountain-spring country like Germany already faces:
Our energy-grid is not equipped for the high fluctuations nature provides in energy. We often have to use foreign energy grids so that ours doesn't collapse in times of high renewable energy input. The plagued neighbours repeatedly threatened to cut us off from their network if we proceed to do this
In the meantime, these energy dumps on our neighbours grids are re-labled as proof that the renewable energy agenda works because we became "net energy exporters".
Also, our grid isn't equipped for it because of the geographical dislocations of renewable power sources and where our industry clusters are. Thus creating the need for a "energy autobahn", basically 2-4 Gigawatt landlines.
It doesn't help that the same backwards-thinking that got us into quitting nuclear is actively engaging against the "electro-smog" of these new-to-be-built landlines, forcing those lines underneath, which is multiplying the costs.
Also, with the energy gap that's about to happen in Germany our neighbors are actively building nuclear plants right across the border. So if you had any fears about nuclear fallout ... well done!
Finally, all this massive undertaking results in chiseled government redistribution programs that amount to a humongous bill that ultimately those people will have to pay the most, that made least use of the redistribution programs. For instance: rich farmers estates are littered with subsidized solar panels, which produce energy that the energy companies have to buy for a constantly rising government-set minimum price. Those companies of course are sharing the costs with their customers, which includes everyone and the poor).
However, I invite you to visit my country. Pick any date in the year but two months and you'll see: "capacity batteries for solar" are not our problem with solar ;-)
Actually, I think a lot of the problems facing Europe with renewables are the same in the U.S. Abundant solar and wind available in the south, and no efficient way of transferring the electric power north.
This article has some more up-to-date numbers regarding renewables. The share was already at 27% in 2014, 2016 will likely have more than 30%. I don't have 2016 numbers, but the growth in renewable production was 37% 2012-2015. And most of that growth came in 2015 with the plummet in prices for solar and onshore wind.
This does not look good:
https://upload.wikimedia.org/wikipedia/commons/a/af/Electric...