I don't have a link at hand, but I remember a study for Germany that the difference between production at night and at day wasn't the biggest issue, but the pro

I don't have a link at hand, but I remember a study for Germany that the difference between production at night and at day wasn't the biggest issue, but the production in summer was so much greater than in winter. If you would just produce enough renewable energy for 100% of the yearly energy consumption, you wouldn't only have to store the energy for the night in batteries, but you would need to store several months' energy consumption in batteries to make it through winter.