Balcony solar panels can save 30% on a typical household’s electricity bill and, with vertical surface area in cities larger than roof space, the appeal is clear
Effectively cutting 30% of electricity going into the household isn't going to help the environment? It means less transmission losses. It means less grid infrastructure which consists largely of copper and steel, which both produce a lot of emissions in their production.
Even if it did nothing for the environment, local energy independence is still such a massive boon to any community that it can't be overlooked.
While the panels are important, the main reason why its important to also have the battery component is because most people tend to work when daylight is out (where the house is theoretically using up the least amount of power) thus, if one didn't have a battery, its pushing the power back into the grid. At the same time, power usage tends to spike when it gets closer to night, where solar is ineffective, and relies thus back on the grid if there's no battery. While personally(not the original person) would never claim it does essentially nothing, the battery component is extremely critical for energy independence as the time period people want to minimize grid usage the most should be during the peak hours, which inconveniently is when the sun is down.
Your are mostly wrong. Infrastructure is still required because sun isn't shining through night and short cloudy winter days. Also Germany has plenty of solar and other renewables power already, specially during day. So it could be that almost all the electricity during sunny days are already coming from renewables. This balcony thing is far from independence.
The problem being that for many people bigger is not possible. If you don't own the house, you don't have any other possibilities. And even without a battery: if you time washing and or drying your clothes right, there is quite a possibility to save money.
The idea here is that you're directly pulling from the panels as first priority to take a chunk off your utility bill. The energy it provides never needs stored, and it makes the load lighter for transporting green energy from elsewhere.