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‘If 1.5m Germans have them there must be something in it’: how balcony solar is taking off
(www.theguardian.com)
This is a most excellent place for technology news and articles.
In Germany those panels usually pay themselves after about 5 years depending on the price of the necessary electronics (don't forget the electricity meter!) and if there's also a battery.
You don't need a smart meter for this, just plug and play. If seen offers for complete sets from as low as 250€ in supermarkets, so almost everyone can get one and start saving some power.