Just to add a bit of context: 50% sounds great, but Germany uses ~3.7PWh of energy only 0.6PWh of which is electricity. Renewable energy production is 8% of energy consumption. No large-scale storage needed if 92% of your energy can be generated from fossil fuels on demand. So far so good, but we have much more than 92% of the work still ahead of us since it will become harder as we need storage and use up the available physical space.