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I know some people have solar panels and produce excess power that they then sell back to the grid. Since they generate some amount of power that they could sell back to the grid.

So hypothetically, if my neighbor and I were the last two loads on the power line, is it conceivable that If we were to experience a blackout, that I could get power off of my neighbors solar panels? (Additionally, if multiple houses kept their load under what was supplied off the solar panel, then could they all share the output?)

Edit: I realize a lot of answers have been posted, but for the original intent of this question I was curious about transferring power from my neighbors house to mine using only existing municipal wiring (eg: not bringing suicide cords or the like into the mix)

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    if the grid is down, the panels will not backfeed into the grid. Well, unless they are using a highly illegal and dangerous setup. You could run a cord from their downstream outlets though. – dandavis Feb 15 at 20:02
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    No. Grid-tie inverters don't work that way, for very good reasons, such as not killing linemen. – Ecnerwal Feb 15 at 20:03
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    Roof top panels are usually on small side providing much power. With a power outage both houses would only be able to power a couple of things at a time, if panels supply power to the house, not to grid. Some supply power to grid and electric company reduces/rebates electric bill. – crip659 Feb 15 at 20:47
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    @Sidney Will you have separate wiring system connecting your house to your neighbor's house directly, or would you be relying purely on the existing municipal power lines/system? If the latter, the answer is definitely "no", if the former, the answer is "maybe, but there's a big risk of electrocution and a guarantee of violating acceptable code". – TylerH Feb 15 at 23:10
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    Only if the sun is shining. Brightly. – FreeMan Feb 16 at 12:08
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Nothing easier. You just need the right gear already installed and ready.

Here's the problem. your neighbor's solar panels are UL 1741 compliant, meaning they are only capable of "Grid Following" - for safety reasons they actively sense the presence or absence of the outside power grid, and shut off altogether when the external grid is absent.

Fortunately, Superstorm Sandy happened. And lots of smug, solar-owning East Coast business leaders and influencers got a rude awakening and told the market "Fix this!"

Turns out it's not an easy problem.

You'll need to create a local "grid" that looks, walks and quacks like a grid to a UL 1741 grid-tie inverter. A random inverter won't do, you'll need a grid-forming inverter such as a Schneider 40xx. This will fool the solar panels into powering up and doing their thing.

At that point it's a simple matter of disconnecting your neighbor's UL 1741 inverter from the utility and connecting it to your micro-grid. (remember not to backfeed the grid here!)

However... To form a grid, you need a power source. You need a battery for other reasons - as a buffer for a bunch of things, and since you have a battery, might as well use it for that power source. All the commercial gear that does this is built around that assumption, so you're stuck with it unless you want to get an EE degree and build your own.

Once you have established your micro-grid, it's as easy as rewiring your neighbor's UL 1741 grid-tie inverter to talk to your micro-grid instead of the utility grid. Again, don't backfeed the utility grid!

You also need to isolate your own microgrid from the utility grid. There are some sophisticated ways to do that. However I'm all for just using a utility/generator interlock on a "critical loads" subpanel (and by the way if you put every circuit in your house on it, I won't tell ;) You can't use the main panel for that, because certain loads have to be on the utility side.

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There is disconnecting hardware to prevent backfeeding into the grid when the power company loses power. These disconnects are similar to the transfer switches required on generators. The disconnecting device is usually or can be locked and inspected by the utility that feeds the grid. It would be highly illegal and dangerous to try and bypass any of this equipment. Just run some extension cords from you neighbor to your house.

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    And not suicide cords /cables!! – whatsisname Feb 16 at 1:25
  • Come on Jack. Didn't expect that answer from YOU. Has this site become that complex? Why can't the guy use extension cords like the rest of us grubby neighbors? – DMoore Feb 16 at 8:12
  • @DMoore lol Well the OP did ask about feeding out to the pole and then back in through his service drop since they were the last two. .. and i just got my vaccine so was a little lightheaded.. :-) – JACK Feb 16 at 12:47
  • This is close to what I said a generator inlet with a lockout could feed the 2nd home through a cord. But the grid tied system has to lockout or island properly prior to allowing the system to generate power. – Ed Beal Feb 16 at 16:05
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There are several possible answers to your question. First if your neighbors system is grid tied most shut down when the power goes out.

If there system can “island” them it may produce power for them to use (with the power out this is EXPENSIVE) not many go for the extra expense.

Could you (with there permission) use some of there power? This would be like hooking a generator up with a suicide cord.

if you had a proper power inlet and interlock it could work but only ? 1 ? and this would surprise me if there system would be that large. (That’s why I said only 1). It could not back feed onto the power lines that is what “island” means they are in there own power island.

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  • How is it "EXPENSIVE" to generate energy yourself instead of getting it from the grid when the grid is off? This seems 100% counter to the idea of getting solar panels in the first place. I would expect power generated when the grid is down to be free, because you're generating it, not the power company. – TylerH Feb 15 at 23:08
  • It is the equipment that is expensive. Most grid-tie (meaning connected to the utility lines) solar system inverters automatically shut down when they lose the grid connection as a safety precaution. Otherwise they could send power back into lines that the utility workers thought they had shut off to work on. Literally a matter of life and death, so this is the standard, and the equipment necessary to allow you to still use your panels needs to be as robust and fool-proof as possible to make the authorities assured that it is safe. It is this next level of equipment that costs a premium. – Blobfish Feb 15 at 23:25
  • If you make a stand-alone system (NOT tied to the utility), then you are free to use the power you generate. Only complication is being able to store that power for use at night. Banks of deep cycle batteries are an added expense and require maintenance and ventilation. Still a good option, just not as cheap as a grid-tie system, and you don't get to sell excess power back to the utility. – Blobfish Feb 15 at 23:28
  • Don't know why the down vote on this. Most systems tied to the grid will just down when the power goes off. If you have installed batteries, then you can use saved power. If you have a stand alone system, then you can do what you want. +1 – JACK Feb 16 at 15:41
  • @tylerh the cost of setting up the extra hardware was aprox 2k so there is a extra cost if daylight and the power is down to produce solar. Most of the homes that have asked about making the conversion realized it was not economically realistic to add the island feature to a grid tied system. When a gas powered generator of similar size to the solar array was 1/2 the cost and the gas powered generator did not need the sun, if you add batteries and charge controllers so you could run everything at night now you can purchase a pad mounted generator that will run most homes. – Ed Beal Feb 16 at 16:17
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I don't know what the other answers are trying to solve.

Based on your question you need a high quality long 10 gauge extension cord, maybe a couple... Sometimes big issues need simpler answers. During an outage his solar panels will not be able to power your furnace or AC but he can hook you up to whatever power he has. There is no reason this has to be hard wired unless you have some expensive delicate stuff that has to be at a certain temp... and then you should get your own generator.

The idea of neighbors tapping into other neighbors power during outages has been going on since electricity was implemented. Extension cords have always been easiest and safest.

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  • @JACK - I get the edit but the edit doesn't make sense. Why do you need municipal wiring between two dwellings? Who would sign off on that? Not any city near me. There is no difference between any setup described in other answers or running an extension cord. You can still capture the power into a generator. Honestly this has turned into a terrible question with no real world practicality unless aliens invade and are sending down arbitrary power rules. – DMoore Feb 16 at 19:31
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The solar photovoltaic system installed on my house does not provide power if the grid power is unavailable. As noted in the comments, this is to protect linemen, but also to prevent power being distributed in the manner described in the question. It's been difficult to explain to people that we don't have power when it's out, grid-wise.

That was in the past. Nnow that we have a battery backup system for the entire house, the system is configured that we can pull power from the solar panels and from the battery when the grid power is lost. There is still a disconnect in the circuit but it's upstream of the solar panels.

I've discussed with my neighbor about being able to run a line to his refrigerator if the outage is going to be of an extended duration. Due to the current (amperage) limitations of this system, it's not like I'll be able to power half his house, but if he uses an extension cord of sufficient capacity, there should be minimal power drop over the distance.

The last part of the question can be answered thusly. Most homes have only sufficient power generating capacity to operate one house, sometimes not even the entire house.

Powerwalls and the concept of whole house uninterruptible power is a recent development in PV systems.

If the foundation of the question is "can power be drawn from the neighbor's PV system," the answer is yes if there's a battery backup system functioning, no if there is not. The yes answer is not correct for the specific question of using utility lines. That's a solid NO.

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    "the system is configured that we can pull power from the solar panels and from the battery when the grid power is lost." So does this mean the system installed on your house actually does provide power when the grid is unavailable? You have conflicting information here, and it seems only to be anecdotal rather than answering the question asked, which is "can I draw power from my neighbor's solar panel system", not "will my neighbor's solar panel system be strong enough to fully power both their house and mine". – TylerH Feb 15 at 23:07
  • @tylerh as I said there are multiple answers, Fred had a standard grid tied system no power from the power company that system shuts down, then a battery backup was used this is more like a conventional interlock so that can be done, there are island systems that isolate the inverter for the grid tied system and can feed that power to the home. Just because you have limited experience don’t discount others examples there are 2 on just this page that have done it and there are more than these 2 ways to do it.+ – Ed Beal Feb 16 at 16:44
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    @EdBeal I'm not discounting fred's experience, just questioning how it answers OP's question (and asking him to reconcile the conflicting statements in his answer). FWIW I recently helped my parents through a solar installation project and their project is grid-connected to feed surplus power back to the grid, and included batteries for critical utilities while the grid is out. From what I found during the process, their setup was a 'standard' one. – TylerH Feb 16 at 17:19
  • updated answer to reflect new comments – fred_dot_u Feb 16 at 18:48
  • @Tylerh, your parents have battery backup ok great but what happens to the array power when the grid goes down? Your 1 off experience gives 1/2 of an example. There is no double speak in Fred’s answer he started out straight grid tied (typical) in 5 years or less when the new added battery’s are shot the owner that runs the numbers usually adds a gas generator. I have one outside the shop 24kv we are installing for power loss, also a propane tank the generator with the transfer switch was $5.4K and a 12 week delivery. This is the most common back up I see but usually a much smaller generator. – Ed Beal Feb 16 at 18:52

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