Comment on ‘If 1.5m Germans have them there must be something in it’: how balcony solar is taking off
schnokobaer@feddit.org 14 hours agoThe “balcony” bit isn’t the defining characteristic, it shouldn’t be taken literally. Some people do have their “balcony solar power” on their roofs.
What defines it is limitation to 800 W and inverters that come with a normal Euro Type F (“Schuko”) plug and no legal requirement for professional installation. A layman can literally plug it in to an existing wall socket. Given that they are capped at 800 Watts, the inverters are also the simplest type and dirt cheap (although often they are literally just software-capped and identical to higher power ones, make of that what you will). Complete systems (2 panels, cabling, inverter) cost between 299€ and 800€ depending on quality. You genuinely only have to buy a fixture that suits your needs and a mate to help you install it.
Proper several-Kilowatt-systems are very expensive in Germany too.
Buffalox@lemmy.world 14 hours ago
Thanks really good info. 👍😀
I had no idea that is possible??? Is that special for Germany? (sorry for keeping on with new questions). 😋 I’ve never heard of that option here in Denmark.
No wonder it’s a popular option, our system is of course bigger with 11.2 kWh and 7.5 kWh battery. but it was $17000 1½ year ago. Prices have dropped to $12500 for a similar system, but still such an 800W system is dirt cheap by comparison.
schnokobaer@feddit.org 13 hours ago
I mean, the regulation seems to be, but there’s no fancy tech going on. I’m not an electrician but I think I can explain, as I have recently tried to understand it as well.
So German wall outlets usually have a 16 A fuse and the wiring in the walls is dimensioned for safety reasons to accommodate slightly higher current (I think they are 2.5mm² gauge allowing up to 20 A but don’t quote me on that particular part). I suppose it would be the same or very similar in Denmark, or maybe most of Europe that uses 230V/50Hz AC.
Now, normally, if you have dangerously powerful load that would melt your wires, let’s say 5 kW, and you plug it in to an outlet the fuse will just pop and you’re safe. If however you have a 2 kW PV system connected to a wall outlet nearby, it would theoretically be possible that your 5 kW load draws 13 A (3 kW) from the mains through the fuse and another 8.7 A (2 kW) from the PV system over the same wire in the wall that is only rated at 20 A but now carries 21.7 A. And the fuse would never pop at 13A. A fire hazard. The number of 800 Watts is basically just what will always comfortably fit into the safety margin of the wiring in German houses. All higher power systems need to be hardwired “behind” the fuse box so that every Amp goes through the normal 16 A fuse.
Absolutely. I guess the low threshold for installation allows some kind of mass market economy of scale.
Cocodapuf@lemmy.world 10 hours ago
Great post! Thanks for doing the math and explaining the concepts!
Gerprimus@feddit.org 13 hours ago
There are already a few requirements for operating the balcony panels, At least here in Germany:
I think it’s almost irrelevant how many panels you ultimately split up. However, no more than 800 watts may be fed in.But if you have panels with, let’s say, 2000 watts, you can of course charge various batteries with them beforehand. Nobody can say anything against it.
DacoTaco@lemmy.world 11 hours ago
Just for your information : belgium is allowing the balcony solar panels this year, but they have put limits on which you can install. The power supplier needs to have approved the kit you install. This is just to prevent people from getting cheap crap from the internet.
Other than that, same rules!
Deway@lemmy.world 4 hours ago
Wait really? I didn’t know we finally caught up with the neighbors!
Buffalox@lemmy.world 10 hours ago
That makes sense, we also needed new meter, and that was about €200.- with installation. Not a big deal for a big installation, but for a system that can cost only €300.- an extra 200.- would be pretty significant.