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
A layman can literally plug it in to an existing wall socket
That’s amazing, 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.
cost between 299€ and 800€
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.
There are already a few requirements for operating the balcony panels, At least here in Germany:
You need a suitable electricity meter
You have to register with a relevant authority and inform the electricity provider that you are operating a “balcony power plant”.
The microconverter should run on its own secured circuit. (“Should”, will certainly do very few)
But technically it is simple:
Set up panels
Connecting necessary plugs
Microconverter to the socket
Be happy that you produce up to 800 watts of your own electricity
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.
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.
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!
I had no idea that is possible??? Is that special for Germany?
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 myself. To understand why it’s possible it’s best to understand why the limit is at 800 W precisely.
So German wall outlets usually have a 16 A fuse and the wiring in the walls is dimensioned 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) for safety reasons. 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 13 A, making it a huge fire hazard. 800 W is basically just what will always comfortably fit into the safety margin of the wiring in German houses. All systems above 800 W need to be hardwired by professionals “behind” the fuse box so that every Amp from your PV goes through a typical 16 A fuse.
still such an 800W system is dirt cheap by comparison
Absolutely. I guess the low threshold for installation allows some kind of mass market economy of scale whereas systems like yours are homeowners’ luxury goods.
Thanks really good info. 👍😀
That’s amazing, 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.
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.
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.
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!
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 myself. To understand why it’s possible it’s best to understand why the limit is at 800 W precisely.
So German wall outlets usually have a 16 A fuse and the wiring in the walls is dimensioned 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) for safety reasons. 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 13 A, making it a huge fire hazard. 800 W is basically just what will always comfortably fit into the safety margin of the wiring in German houses. All systems above 800 W need to be hardwired by professionals “behind” the fuse box so that every Amp from your PV goes through a typical 16 A fuse.
Absolutely. I guess the low threshold for installation allows some kind of mass market economy of scale whereas systems like yours are homeowners’ luxury goods.
Great post! Thanks for doing the math and explaining the concepts!