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Germany outfitted half a million balconies with solar panels

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Re: Germany outfitted half a million balconies with solar panels

#21

Post by geor9e »

monero-xmr wrote: post #11
lm28469 wrote: post #2

I'm in Germany and keep seeing these, I always wonder what a 400w poorly oriented panel getting like 3 hours of sun a day is good for. If they weren't basically free thanks to tax reduction and other tricks I assume no one would get them

Maybe these can pull 700 watts on a sunny day? And you’d need a battery to store it. Would likely make 50 cents a day or less in electricity, on perfect days. The cost for a battery, panels, and install would be ~1000 euro (or more if it’s a bureaucratic mess).

They don't use a battery; they just supplement your apartment so you use less grid.

Re: Germany outfitted half a million balconies with solar panels

#22

Post by colechristensen »

lm28469 wrote: post #2

I'm in Germany and keep seeing these, I always wonder what a 400w poorly oriented panel getting like 3 hours of sun a day is good for. If they weren't basically free thanks to tax reduction and other tricks I assume no one would get them

Solar is cheap, non-peak-efficiency installs get to be the priority once you get the first 40% or so of production in solar.

This kind of thing just knocks the edges off of production and transmission costs. You get to the point where you're not trying to squeeze peak efficiency any more and you're just trying to fill in spaces wherever works reasonably well.

Re: Germany outfitted half a million balconies with solar panels

#23

Post by danielheath »

lm28469 wrote: post #2

I'm in Germany and keep seeing these, I always wonder what a 400w poorly oriented panel getting like 3 hours of sun a day is good for. If they weren't basically free thanks to tax reduction and other tricks I assume no one would get them

"Poorly oriented panel" can equally well be described as "generates most of its power in the evening, when you have gotten home from work and want to use electricity".

It's better to get power at a useful time, even if that means the panel only generates half as much as it could, because storage costs far more than panels.

Re: Germany outfitted half a million balconies with solar panels

#24

Post by lucb1e »

ViewTrick1002 wrote: post #14
lucb1e wrote: post #8

Earlier quoted context omitted.

That's like saying the cost of taking an additional bite from your food is very low once you have already bought it, if I'm understanding the continued use of marginal correctly in context?

Assuming you have an endless supply of food but can only take one bite per day and it means tomorrows bite will be a bit smaller. These storage systems are generally warrantied as 5000-10000 cycles with 85% capacity remaining in 20 years time. Guaranteed money today is better than saving a few cycles to maybe make money in 20 years time. Now also factor in discounting the risk etc. and the calculation is given. But t…

Okay, I can follow that. I've noticed on electricitymaps.com that, for Germany, the coal component never disappears, no matter if you have optimal wind+solar conditions near the summer solstice and prices are far into the negatives. Apparently it's cheaper to let it run the power plant at negative prices for days, than to make it stop burning coal for those days. That renewables with storage would make that finally go away stands to reason

But that fully relies on storage. The person you were responding to was asking whether small-scale solar panels make sense. As it is, during those hours where your solar panel is most effective, you can sign up to receive money for drawing electricity from the grid (if prices are negative enough that it outbids even the transportation costs and taxes). Having a solar panel at that time... you might as well turn it off and get a price that's better than free. Storage would be what we need much more urgently than an extra 800Wp solar per household, then we could already turn off those coal plants for probably weeks at a time during summer

Re: Germany outfitted half a million balconies with solar panels

#26

Post by dzhiurgis »

lm28469 wrote: post #2

I'm in Germany and keep seeing these, I always wonder what a 400w poorly oriented panel getting like 3 hours of sun a day is good for. If they weren't basically free thanks to tax reduction and other tricks I assume no one would get them

It's 800 watts or about 570 KWh per year in berlin, assuming balcony points directly south. At 0.2 euro, that's about 114 euros per year.

Percent-wise I'd guess it's less than 10% of yearly total?

Overall it's OK payback, but mostly penny pinching in grand scheme of things.

https://globalsolaratlas.info/map?c=48.886392,9.470215,6&s=5...

Re: Germany outfitted half a million balconies with solar panels

#27

Post by Kim_Bruning »

monero-xmr wrote: post #11
lm28469 wrote: post #2

I'm in Germany and keep seeing these, I always wonder what a 400w poorly oriented panel getting like 3 hours of sun a day is good for. If they weren't basically free thanks to tax reduction and other tricks I assume no one would get them

Maybe these can pull 700 watts on a sunny day? And you’d need a battery to store it. Would likely make 50 cents a day or less in electricity, on perfect days. The cost for a battery, panels, and install would be ~1000 euro (or more if it’s a bureaucratic mess).

I just did some modelling with the help of claude (which can write 200LOC+ numpy code faster than I can)

300 Euros crappy setup, 600 euros mid-range setup, 1200 with storage. (Extra) regulations is zilch, it's legal to plug and play these things up to 800W nameplate capacity.

I went with numbers for mid-range, vertical south orientation and offsetting 200W (without battery, any overproduction is wasted). This nets you an avarage of €0.32 per day - With practically nothing in winter, and maybe up to €1 per day on a PARTICULARLY nice summer day.

But altogether, that still adds up to something like Eur 116 per year, so your midrange system earns itself back in 5-6 years.

Not great, not terrible. Nothing to write home about, but free money is free money.

Re: Germany outfitted half a million balconies with solar panels

#28

Post by jay_kyburz »

WaitWaitWha wrote: post #13

Great idea! Want to learn more on the safety though... > Once in place, people simply plug a micro-inverter into an available wall outlet. later >Gründinger and experts at the German Solar Industry Association noted that the devices don’t generate enough power to strain the grid, and their standardized design and safety features allow them to integrate into balconies smoothly and easily. This seem to talk to the safe…

[flagged]

Re: Germany outfitted half a million balconies with solar panels

#29

Post by astro1138 »

duxup wrote: post #10

I wonder how useful those are just small panels hanging off the side of a balcony oriented poorly. They also kinda look terrible :(

When it comes to urban design, I consider balcony solar panels to be less of a nuisance than cars on the streets.

Re: Germany outfitted half a million balconies with solar panels

#30

Post by duskwuff »

dathinab wrote: post #18
drnick1 wrote: post #16

[flagged]

there is nothing lol about it, if you commonly connect anything larger without additional precautions to it you end up in an endless number of safety hazards and guess what if you do take extra steps you also can have larger solar systems sure non of this steps are practical for rented out apartments, but quite viable for owned apartments and houses

I'm not sure what kind of laptop you're using, but most laptops I'm aware of use considerably less than 800W. :)
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