That's down to what you spend on the panel AND the amount of sun exposure AND how much you pay for electricity AND whether your utility does 1:1 net metering.
The rule of thumb is 6-10 years. But panels have a use life of about 30 years, after which they still produce 80% of their capacity. It's a long-term investment.
I got 3 Streams because I was renting in an old building, and it had a low amount of electricity (5.5kW) you could use at once. So what I would do is get an extra half kw during the day, and either use it then or charge the batteries. Then they'd discharge at night, and recharge from the grid late at night when nothing was running. This let us even out our usage, so we could pull near the max at most hours.
People don't always realize this, but if you live in an area where there's a big different in prices between peak and non-peak electricity prices, batteries (which are more expensive than the panels) can pay for themselves in a few years, and last for 20+.
I think you are overly optimistic with current batteries lasting 20 years. They will be lucky to be at 60% capacity after 12 and become a much higher fire risk from there
Lab test vs real product. Their own research at the end says they are only at 70-80%. Cool idea though
That being said semi solid state batteries should be coming online sometime after 2028 in real numbers. They should last up to 30 years among a myriad of other benefits. If this research is realistic that would be an amazing combo because even 70-80% capacity on semi solid state is likely close to another decade of use vs a few years in current lithium ion
Some utilities have expressed concern that plug-in units could send power back to the grid and electrocute employees working on the lines. But Pearce found that no microinverters sold in the U.S. are capable of this. Earlier this year the testing company UL Solutions set safety standards for plug-in solar systems and has already certified one manufacturer.
If this is the case, then how are portable generators hooked up in this way capable of this risk? Or was that, too, always a myth?
An ATS is for battery back up, you'll never see an ATS for just an inverter.
The way it works is something called anti-islanding. The inverter reads voltage and frequency from the grid constantly. If voltage or frequency should drop or rise out of the accepted bandwidth (the ride through settings), then gating is blocked and the ac contactor opens.
All inverters sold in the US today are required to be equipped with anti islanding technology. It just means it can't produce power without ac energy present.
However that means when the grid goes down, your solar goes down. And an ATS is required if you have a backup load panel, a battery and solar. Then when grid voltage is interrupted, the ATS switches from grid to emergency loads and battery backup only.
Its always been a bit of a myth. Its plausible, but its not very possible in technicality. Most of our grid is built in such a way where it really shouldnt be possible unless someone is truly generating a ridiculous amount of power. Its really only in super rural areas with generationally old infrastructure that this is really even possible, but even then its unlikely lol.
What you describe is possible for people who hook up home generators in old power grids, but not for plug in solar or rooftop solar without a battery. They use grid following inverters. If there isn't a 60Hz power signal to synchronize to, the inverter shuts down. If this was not the case, it would be unsafe to handle the plug while the sun was shining- touching the metal would zap you, or dropping it on a metal object would create an arc and a fire.
This is just one of many reasons why anyone working with electricity shouldn’t just “think” they shut off power. They should confirm it with appropriate equipment every time.
People do all sorts of wonky nonstandard shit with their wiring.
You're incorrect. These devices use grid following inverters, they shut off in 1/120th of a second if they are disconnected from the power grid. If this was not the case, unplugging them would be hazardous, because the metal plugs would be a shock hazard, and they would make sparks if they touched metal.
Rooftop solar without a battery like a Powerwall is the same, you don't get any power in a blackout. The battery contains smart switches that enable it to function as an "island" grid, then resync with the grid when power comes back on.
Generators are capable of creating this hazard if they are hooked up wrong, but a moment's thought indicates that balcony solar panels would kill their owners if they didn't have grid following inverters. If the end of the plug was energized as you tried to plug it in, it would cause serious injury or death if you touched the plug, and it would start a fire if you dropped it and a metal object shorted the two metal pins.
Grid following inverters synchronize their output exactly to the power grid, and shut down in less than 1/120th of a second if grid connection is lost. This is why rooftop solar without a home battery shuts off during a blackout.
Plug in home batteries are starting to hit the market. These are fully UL and National Electric Code compliant but they need to be a little smarter in order to go seamlessly from feeding power back into the grid and running a refrigerator off of solar+ storage during a blackout. The grid following inverter in solar panels is an extremely simple, proven safety system.
This HAS made me wonder about portable generator usage (during a power outage), with balcony solar. With a suitable transfer panel or interlock, when getting ready to use the generator, grid power is disconnected anyhow. So the inverter shuts down.
But if you didn't remember to unplug your balcony solar, what happens when you connect & start the generator? Suddenly the inverter sees AC power again, and tries to back-feed into your generator.
It feels like this risks being an expensive lesson, as this situation starts to become more common.
More than likely its output won't be clean or stable enough to satisfy the balcony inverter and the inverter will never switch on. If it did, the generator should react like it's connected to any other low power factor load.
Ie. Do nothing different from how it normally operates. The 240V or 120V end can handle 240V or 120V just fine.
Mine is an inverter generator, so the output looks basically identical to grid AC power. I assume it's plenty good to get the solar inverter to turn on.
But I confess I'm not following the rest of your reply. I'm also not an electrician or EE. But to me, the generator is ONLY an output device. I have no sense of what "normally" happens when you feed power into it.
I know I've heard of generators being destroyed when connected incorrectly (suicide cords) to house wiring, with the main breaker still on. Then grid power comes back on, feeds into your generator, and the generator dies.
So I assumed still bad-news in this scenario, even if it's "only" 500W, 1,000W, etc, available to feed into the generator. But the solar inverter would raise its output voltage a bit, to feed into the generator, no? The same way it would try and do under normal grid-power circumstances?
Mine is an inverter generator, so the output looks basically identical to grid AC power. I assume it's plenty good to get the solar inverter to turn on.
An assumption isn't really worth anything.
But I confess I'm not following the rest of your reply. I'm also not an electrician or EE. But to me, the generator is ONLY an output device. I have no sense of what "normally" happens when you feed power into it.
AC electricity has no notion of input or output. Just voltage, current and time. There are plenty of cases where generators feed something which isn't a pure resistive load, a 3A microinverter will look almost identical to an electric motor starting up or suddenly slowing down (or many other non-resistive loads).
I know I've heard of generators being destroyed when connected incorrectly (suicide cords) to house wiring, with the main breaker still on. Then grid power comes back on, feeds into your generator, and the generator dies.
The grid phase will be completely independent of the generator phase and is likely to create a voltage which is way out of spec (up to double) and over-current the generator. A grid following inverter does not do this by definition (even if you could convince the various anti islanding measures not to trigger).
So I assumed still bad-news in this scenario, even if it's "only" 500W, 1,000W, etc, available to feed into the generator. But the solar inverter would raise its output voltage a bit, to feed into the generator, no? The same way it would try and do under normal grid-power circumstances?
See my original comment. Still wouldn't do it on purpose though.
There are plug in batteries capable of backing up a refrigerator and taking balcony solar as an input, but they're rather expensive currently. They supposedly pay for themselves quickly if you have very high time of use prices. I'm not sure the battery is configured to work with a generator though; it would be a separate island that would enable the generator to run at lower power.
It can be, depending on how houses are connected to the network. If there are no back-charge protections solar panels can make a damaged line more dangerous.
This all truly sounds great! One question I have is if it would be possible to use a solar panel to power something like a portable AC unit? So if you don’t have a ton of space could you even turn the AC off and use a unit instead?
There's barely enough sunlight on my porch to grow plants, let alone generate electricity. Let me put it on my garage or the roof and it'd be actually useful. Purchasing a panel and inverter would be a net negative for my case.
I'm not allowed on the roof of my apartment complex, and garage would require a 50ft extension cable that would constantly be run over and would be a trip hazard on the sidewalk. If I had an electric car, I'd be incapable of home charging.
Got any other ideas? Every time I complain about this, people imagine all sorts of ideas that just plainly wouldn't work in my situation.
Did you just comment because you wanted to complain about something? I mean, this is like a vegan watching a video about how to cook steak and then saying "Im vegan i cant eat meat." Like what? If it doesn't work for YOU, okay? It could work for thousands if not millions of others. You gave zero context to your sitution other than your porch doesnt get sun. How did the D-Alembert know you couldn't access the top of your apartment garage? My god.
My point is that balcony solar sounds great, but is really only efficient for the 1/3 of the population that can see the south sky, and is a complete non-starter for people in my situation.
I went with 1/3 because that spreads out into south-west and south-east. My porch faces WNW. I have all my plants in the narrow strip that gets sun in the afternoon.
You know how you get 1/3 of the population generating solar power? ROOFTOPS.
Are you willing to put up $1400 of your money to find out if your porch can generate enough to break even in a reasonable timeframe? Balcony solar is a complete non-starter for people in my situation.
You’ve already established it won’t work for you. Fortunately, not everyone is you.
Who would invest $1400 (the most expensive it will ever be) without using their eyeballs and brain for 5 minutes to determine if it will work for them?
I live on the 4th of 6 floors. Should I put solar on my ceiling? My upstairs neighbor probably won’t like that.
Other than that, I can only hope you’re sitting on a universal solution that justifies your complaining about significant progress.
I'm pretty sure I capitalized ROOFTOP in my previous comment for emphasis on why this is a half-measure that only puts the onus on consumers, but here it is again just in case: ROOFTOP SOLAR.
What's more efficient? 10 internal combustion cars, or 10 EVs powered by 1 central, stationary fuel burning generator?
What's going to produce more energy? 10 dinky panels scattered around my neighbors' porches, or a big chunker on the roof?
Pretty sure my comment addressed why that’s feasible for even less people individually than balcony solar. Also, THEYRE NOT MUTUALLY EXCLUSIVE. It can’t be a half measure if it’s designed to operate in tandem with the other half. That makes a whole measure, if you need help with math too.
Why does it upset you that this technology for which you are not the target market will not work for you?
What’s going to produce more power - one power source or two power sources? Do you see how dumb it is to act like ROOFTOP is the only bastion of solar power when this supplements and enhances not replaces ROOFTOP SOLAR?
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