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The hero image in this article shows the realities of a lot of balcony solar setups: The panel is held up with zip ties stretched over a large span, which will snap after UV exposure in the sun. That panel is going to fall over in a few months. The remaining equipment and wiring is sitting on the ground, one errant kick away from dangling off the edge. That power cable is probably running through a door or window where it gets squished and damaged each time it’s opened and closed. The panel is mounted vertically and behind a thick glass panel, meaning it will be getting much less sunlight than the sticker rating, which she probably used to estimate her savings.
Balcony solar setups don’t have to look like this, but many do. You can find much better examples from users who do a good job thinking it all through. Often they’re an impulse purchase by someone like the person in the article who want a hobby or the bragging rights of saying they have solar, but for whom the important details like safely mounting everything and running the wires in a way that will survive 10 years are an afterthought.
That’s why I’m starting to change my mind on this balcony solar concept for the masses. I think it would be great if there was a low friction way for qualified individuals to install a reasonable system, but I’m afraid the actual reality will be a bunch of zip-tied solar panels dangling from balconies like this.
But let's be fair here, as you do a lot of assumptions:
The zip ties are metal zip ties. Those won't fall off because of UV. Panel is hanging inside the balcony. If it falls, it will fall into the balcony - it's bigger then the rails and ground is solid. It's not running behind the glass, the glass looks taken off. I can't be 100% sure, but it seems so. You can't see how the power cable is pushed into the home, so that's pure speculation.
The picture looks like taken mid-installation, some metal ties aren't even fastened.
There's probably an outdoor outlet on the deck/balcony it's plugged into. Would be pretty typical to have on a balcony like hers.
The balcony appears to have full coverage on the railing - there isn't a gap at the bottom for anything to fall out through. The metal frame makes it looks like there is at first glance, but look at the seam on the glass - it continues further down than that bottom crossbar.
This might fall over into the balcony some day and break but it shouldn't really be a hazard to anyone else.
Beyond this, the reality is that plenty of the other balconies likely have string lights or other electronic items plugged in 24/7 and with their connectors sitting on the ground on the balcony. Same with having a bunch of unsecured/poorly items that could theoretically get tossed off it by an extreme storm. Not ideal, but I don't see why we should be acting like this is much different from everything else in that sense.
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Now speaking more generally:
- Cities should have reasonable regulations (and likely, already do) about securing anything being positioned where it could fall off and hit someone, particularly over a sidewalk or public space. (As mentioned, I don't think this one is a major hazard upon taking a second glance).
- Balcony solar kits should probably at least ship with some safety cabling and have integrated mount points for those cables that are sturdy enough to withstand wind + drop shocks.
- My concerns in the US/North America are more around how we handle the much lower ratings of our typical residential circuits, it's easier for a consumer to overload a circuit here with something like this than in Europe.
- If we're not requiring a dedicated circuit/single-outlet circuit for it seems difficult to maintain safety unless we're capping the maximum power per system quite low. And if we are requiring a dedicated circuit for it/an electrician to approve it we're greatly limiting who will ever be able to install these.
Overall though, I'm still positive on the concept and don't want to see it buried in regulatory hell, especially with how well adoption has apparently gone elsewhere.
We have a similar approach here in Germany. Anyone has the right to install a small solar system on their balcony or similar and feed up to 800W into their local grid. You just mount it and plug it into your house/apartment grid. Technically you have to get it registered, too.
The sky is not falling, buildings are not crumbling and the grid is not burning.
It's not revolutionary either, but slowly picking up traction. You see more and more installations here in Berlin. On the country side where people have their own house and enough space it's a total no-brainer to set up one of those mini solar systems.
The typical systems you can buy off the shelf (800-1000W panels + inverter) amortize after a few years already, and are getting cheaper every year. I have the feeling the main limitation in the city is having a nice balcony with good mounting points.
The sky is not falling in Germany, buildings are not crumbling and the grid is sometimes overpowered with solar electricity when the weather is sunny, there is not enough demand and grid operators can't remotely curtail small solar systems. Like during Easter Monday
https://www.bloomberg.com/news/articles/2026-04-07/germany-p...
Germany has to invest more in smart electric meters, which could project negative electricity prices to individual households.
And more investments in energy storage systems. (Even through I think that lithium batteries would better help decarbonization in EVs than in electric grid storage systems).
It's worth noting that the common complaint about systems like this, which is that they could cause dangerous conditions during power outages when people expect the power lines to be unpowered, is addressed by electronics that only feed power when they detect an active mains.
Right now, they're about 300 EUR at OBI (major home improvement chain in Germany and Austria) if you don't care at all about avoiding ties to specific apps, and about 1000 from solar specialists if you want to go with the more flexible Hoymiles + OpenDTU inverter setup, 4 panels and a 2kWh (or so) battery, and is one of the few things that has gotten cheaper recently.
Since it's not a battery storage setup, the energy being sent into your home circuit alleviates demand by a small amount. Where did they come up with 10 to 25% savings? Factors such as an optimal view of the sun for as much as possible, south-facing or biased East or West, would be the max. payoff. Night would be a zero net gain. At a savings of $7 a month, the panel would pay for itself in maybe 10 years not factoring in government subsidies. You need to keep it clean as well for it to maintain its potential output.
Stuff like your fridge can use a fair chunk of power continuously and a small solar setup can offset that when the sun is out. Same with routers, chargers, standby devices, TVs, etc.
For a 800W setup, 4–5 kWh on a very good summer day is plausible. Over a full year, it's going to be something like 600–900 kWh depending on orientation, shading, and location. So in strong summer months you might get something like 80–120 kWh. But you won't be able to use all of that unless you have a battery.
However, A typical apartment in Germany is not using that much electricity. Roughly speaking, a one-person place might use around 160 kWh a month and a two-person place around 270 kWh. Finding a use for 20–30 kWh a month during sunny periods. That's how you get to 10%. 25% might be harder but doable if you could somehow have a battery soak up the excess power. I don't think there are a lot of plug and play solutions for that yet. But it should not be that hard to do technically.
Power in Germany is relatively expensive 160*0.40 is about 80/month for me. I pay a bit less than that because I use less power somehow. But still, that's is close to 1000 euro per year. Saving 100 per year means the whole setup would earn itself back in 2-4 years (most plug and play setups you find on amazon are between 200 and 400 euro). And depending on where you live you can actually get some of that back via subsidy. But it basically pays for itself even if you don't. Unless like me your balcony faces east and you only get a few hours of sunlight in the morning.
> Where did they come up with 10 to 25% savings?
I did really rough math and a hypothetical 200W panel getting 100% sun for 5 hours per day (1 kW/hr) would net you a whopping ~$9.30 in savings per month. We're paying something like $0.31 per kW/hr in NYC and it's a lot of money right now.
It may well be in reduced AC bill as well due to increased reflectivity.
It is a thing [1] elsewhere already.
The technology is well understood. It is really a regulation problem, which is why it is coming state-by-state. States are just now even looking at the idea. For a complete list of which states allow it, check out this link https://plugsolarhub.com/states-and-regulations
I live in Brooklyn and have spent about a grand outfitting my apartment with ACs. I would absolutely take advantage of this if the law passed.
You can outfit an entire apartment with AC for a thousand bucks?!
I never understood the economics of these. Say a balcony panel would generate $X worth of electricity for me over the next 5 years. Surely someone who can place the panel on a roof or something, where it is not shaded by a giant building half the day, can generate like $3X from it. It can be part of a bigger installation too, so labor is better amortized. Given that the supply of people with roofs is far from exhausted why would the price of panels be at a level where $X instead of $3X is a reasonable return? Basically you are bidding for panels against an unlimited supply of people for whom the panels are much more valuable than to you, no?
This is primarily for renters of apartments who aren't allowed to alter the roofs. In the US, labor is more than half the cost of a rooftop installation which is hampering their adoption. The balcony solar has no labor cost at all and if the tenant needs to move, they can take it with them to their next rental so they won't lose their investment.
I live in the Phoenix metro area, on the second floor. My balcony faces precisely 225° in azimuth. That is due southwest.
A few years ago, I purchased a "solar backpack" which incorporates a solar panel and a laptop-sized power bank. During the winter solstice, I tried charging the power bank with actual solar energy, and it took more than 3 weeks to fill it up!
Our lease agreement has some concessions for potential satellite dishes and external TV antennas. So I asked my landlady if she would permit me to install solar panels out there. Her answer was a resounding "NO".
It wasn't merely about the aesthetics, but also about the question of hooking them up. Our electricity is unmetered and included in our rent. My unit has an individual circuit breaker box, but how would solar power be fed into such a system? It would be chaos, and the management would have no way of regulating or maintaining such a bizarre setup. I think that's going to be a major logistics challenge for anyone who goes down this road.
> Our electricity is unmetered and included in our rent. My unit has an individual circuit breaker box, but how would solar power be fed into such a system
I don't understand. These systems just plug into wall outlets. The big difference is that, instead of saving yourself money, you'd be saving your landlady money on the bill.
> My unit has an individual circuit breaker box, but how would solar power be fed into such a system? It would be chaos, and the management would have no way of regulating or maintaining such a bizarre setup.
The balcony solar setups are sized to be small enough that they can be fed into standard systems.
There’s no “chaos”. It just offsets consumption a little bit. New electric meters have been able to account for or at least not get confused by reverse flow should it occur at the small levels that balcony solar setups might produce.
A solar backpack is a backpack with a relatively tiny solar panel. It's not designed to power an apartment. It's barely designed to power a laptop. You wouldn't be plugging one of these into the mains.
Solar systems are well understood, as is the business of connecting them to existing power. Magic boxes exist to handle exactly this problem. Connecting them up isn't hard, but installations usually require professional certification to stop people frying themselves and/or their wiring.
DIY solar makes no sense if you're paying your building for unmetered power.
Generally apartment solar can be a nice optional accessory, but very few apartments have the space for a system capable of powering the entire apartment for a significant part of the year.
> how would solar power be fed into such a system
An inverter.
> management would have no way of regulating or maintaining such a bizarre setup
What kind of regulation is needed? What about this is bizarre? If you’re concerned that these systems might be a fire hazard, that’s already a problem (space heaters, heating blankets, hot plates, etc). If you’re concerned that these systems won’t play nicely on a shared AC line, that’s already a problem (e.g., motors). I don’t see anything “bizarre” here.
> Our lease agreement has some concessions for potential satellite dishes and external TV antennas.
This may be because the FCC has pretty strict rules that require apartment buildings to permit dishes and antennas on personal areas like balconies.
Lack of similar laws for solar panels means that most landlords are going to just say "no" rather than take the risk.
You're renting, AND you have unmetered electricity; why the hell would you bother with solar panels?
If anything you should be building a nice home Nvidia AI cluster to take advantage of that free power.
A lot of them just plug into a wall outlet.
And also liability for things falling out of windows.
I live in Berlin and it's quite common here. I personally cannot have it because my balcony has no railing but a low wall that doesn't allow me to hang the solar panel. Plus, you need a power socket easily reachable and that's also a blocker for me, otherwise I would have installed it.
As with window AC units, I worry greatly about the risk of them dropping on people's heads.
But beyond that, this whole backyard/balcony power generation stuff makes me think of Chairman Mao's great leap forward; 'everyone should smelt iron in their back yard' programme. Just so many levels of inefficiency, ignored safety protocols and wasted opportunity to do this at a building, city block, city wide or national level that would actually provide some benefit.
If you live in the sticks, solar and a battery system is maybe worthwhile for redundancy, but all of this is just a waste. Most of these units will be in landfills in a few years, and the production cost in pollution is magically handwaved away.
These are not yet approved in Finland, one reason being that older houses might use thinner conductors to wall outlets that cannot handle higher wattages being fed from solar. Maybe fuses and circuit breakers can prevent problems, maybe not. I am not an electrician.
One fix might be a low ceiling on power output from solar units. Another fix might be to sell solar units that connect _only_ directly into a fusebox, completely bypassing in-wall wiring.
And then there is a question of island mode, so that when the power lines are down, and under repair, you don't accidentally electrocute a lineman.
OTOH maybe I have no idea what I'm talking about.
I read a good article on this technology on CNN.com last month:
https://www.cnn.com/clean-energy-solar-diy-balcony-backyard-...
I live in Virginia, and REALLY want to try this, but I am sure Dominion Virginia Power and my HOA would not be happy; rooftop solar is out of my price range. The article I provided a link to says they are trying to change the laws in the U.S. to enable everybody to do this, and I really hope they are successful.
It's amusing how skeptical Americas are about these renewable projects which are completely commonplace in Europe and Asia. The biggest obstacle to expanding renewable energy in America, is Americans.
>The biggest obstacle to improving America, is Americans.
FTFY.
It’s same same with any change or improvement. Head firmly buried in sand.
> Her 3.5 foot by 3.5 foot solar panel weighs about 25 pounds and is a half-inch thick. It can harvest about 220 watts of energy from the sun each day.
Grrrr. Watts is not a unit of energy.
As a holder of a physics degree this annoys me quite a lot. Journalists seem to have trouble keeping track of energy vs power. It's like saying my friends house is 5 miles per hour away.
/rant off
You have to just close your eyes and hum a requiem for the glory days. Like I do when questions are begged
> Her 3.5 foot by 3.5 foot solar panel weighs about 25 pounds and is a half-inch thick. It can harvest about 220 watts of energy from the sun each day. It’s on the smaller end of available balcony solar panels. The panels can go up to almost 2,000 watts in capacity. A 1,200-watt panel is enough to power a window air conditioner unit, according to Bright Saver.
This whole paragraph is nonsense. A 2,000 watt panel is never going to go on a balcony (because it is huge for any residential balcony), and regardless of "capacity" a solar panel is not going to power a window AC unit without an intermediate storage, unless you want the compressor to shut down every time a cloud passes by.
And people complain about writing being AI generated. Is this kind of sloppy writing any better?
Just wait until you see "kW/h" :)
But I think plug-in / balcony solar will be pretty cool. And I think there's a path to inexpensive, larger, safer grid-tie inverters which never backfeed, but prioritize solar input first and make up the difference with grid power.
For example, I'm imagining a box that would plug in to the wall, have a DC input from solar panels, and a power strip for loads supporting up to, ideally, a full 15A normal US 120V circuit.
Currently this box exists in the form of battery power station units (Bluetti, Ecoflow, Anker etc). But I think there could be a much less expensive form that could exist without the battery.
1lb/kg is a unit of acceleration approximately equal to 4.448m/s^2. Pound of weight, not mass, obviously. This is still more valid than almost anything in the American Journalist system of units!
>As a holder of a physics degree this annoys me quite a lot. Journalists seem to have trouble keeping track of energy vs power. It's like saying my friends house is 5 miles per hour away.
I've ranted endlessly about the outsized impact people with no expertise but a large audience have had on society. So so many people have the worldview shaped by individuals that cannot even bother to learn basics like watts and watt-hours for their "reporting".
I have this peeve too, but tbh it feels like most people make this mistake, and usually it is easy enough to guess what was intended.
Why not being more considerate on how we use electricity? Low wattage lightbulbs, less laundry, shorter showers? Also since aesthetics don’t matter, let’s also hang clothes by the windows so we don’t use dryers.
New York already has some of the lowest energy usages in the US. Austerity will only get you so far, and is politically unpopular.
I wonder what the terminal velocity of a falling solar panel is...
About the same as that of a falling AC unit I reckon.
It’s not hanging from a window… I’m having trouble picturing what that look like.
windows should, themselves, be solar panels. everywhere.
Do these people have any idea how poor efficiency will be when you're mounting perpendicular to the ideal orientation?
This is pure vibes. It makes no sense. And it's really tacky too. Cheap panels hanging off balconies sounds horrible for the aesthetics of an area.
You would hope someone creates panels with cells arranged at an angle so that they point more towards the source. But by then the city will be full of the trashiest junk panels and people only care about the cheapest option anyway.
This can be dangerous for utility company workers.
When a line needs to be repaired, the technician takes steps to ensure the line isn’t carrying current from known sources. A panel plugged in by a civilian via a home outlet is not known. The technician can be killed by the unexpected current.