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Plug in solar- legal in US?

Discussion in 'Energy, Environment, and Policy' started by brkaus, Sep 27, 2019.

  1. brkaus

    brkaus Well-Known Member

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    Is something like this legal in the US?

    Legion Solar 4 - Permission Free Energy and Storage

    they make the statement that it is OK because they measure & throttle generation to eliminate any power going back on the grid. Therefore, they claim it isn’t grid tied.

    they also provide some guideline for circuit to plug into. But, of course, disclaim any responsibility. Not reviewed for code, etc.

    My assumption is not legal, but if it is illegal, what statute makes it illegal?
     
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  2. Ampster

    Ampster Active Member

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    After a cursory review it appears to have a battery and may operate like a UPS. Devices would have to plug into the unit to avoid any codes issue. Does it have a UL rating? The building code would make it illegal if it is installed on the roof without a permit. putting it on a patio cover may not violate building code. It is not breakthrough technology.
     
  3. brkaus

    brkaus Well-Known Member

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    The lowest option is a panel, micro-inverter, controller and a plug you plug into an outlet to offset regular house consumption.

    it has a CT on the main and cuts production when house goes to 0.

    the next level has battery, but they still encourage it being plugged into an outlet to offset house use.
     
  4. iPlug

    iPlug Member

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    Anyone know if there is a stand-alone home battery product out there similar to what Legion Solar is working on?

    I think such a thing would be more useful. Many of us already have home solar PV and at maximum capacity needed. Additional panels with this do-it-yourself solution could not be roof mounted by code and would likely be installed in less appealing/sturdy places on the property.

    Imagine an expandable modular home battery you could plug into a 240v outlet in the garage or utility room, say a NEMA 14-50 with a splitter where a charging station is already installed.

    It would not work for off grid applications as such as would require built-in anti-islanding to shut down if the power goes out as a safety measure for both grid workers and if unplugged to prevent back-feed through the exposed prongs.

    But this could be quite useful for TOU peak shaving. Not requiring any installation costs could save a good chunk of change as the install level would be essentially "novice".
     
  5. T3slaOwner

    T3slaOwner Member Extraordinaire

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    Why is putting it on your roof illegal without permits? Maybe that's just a thing where you live? it's funny that they claim 120 volts is safer somehow. lol Seems like a throwback to the Edison/Westinghouse DC/AC electrical rivalry.
     
  6. Akikiki

    Akikiki A'-Lo-HA ! y'all

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    I am not going to try to track down the federal statute on the federal tax credit. But as I recall, one of the considerations to qualify for the federal tax credit includes installation by professional installers/electricians. At least check it out thoroughly before you put money into it.
     
  7. Texas-Rich

    Texas-Rich New Member

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    There is so much wrong with this concept that I don't know where to start. I am in the solar industry and I want to try and explain why this is a really dangerous thing to do. First I will say that It will absolutely work and for somebody that that understands what they are doing and that knows how their receptacles are wired and what circuits they are on. OK.. hopefully I can explain why I think this is a dangerous concept.

    A 120V receptacle is normally on a 15 AMP breaker.

    There are usually multiple receptacles on a circuit. The circuit breaker and the wire for that circuit are usually designed for 15AMPS.

    NOW, lets plug in a 10 AMP load on that circuit... AND inject another 5 AMPS from the solar array that you just plugged into that circuit...

    what is going to happen?

    The 5 amps of solar will serve that 10 AMP load and an additional 5 AMPS will flow from the main load center through the circuit breaker to service the load. FANTASTIC you are only buying 5 AMPS instead of 10. All is good in the world!

    NOW, what if somebody plugs in more loads to that circuit. lets say that now you have 18 AMPS of total load on that circuit with the same 5 AMPS of solar being injected.

    Without the solar the breaker would trip but because the 18 AMPS would have exceeded the 15 amp breaker limit.

    BUT now you are not pulling 18 AMPS through the breaker you are only pulling 13 AMPS through the breaker BUT you are injecting an additional 5 AMPS of solar into that circuit.

    you are now potentially OVERLOADING the wire. (depending on which receptacles the loads are on and where the solar is back feeding into the circuit)

    That wire is going to start getting hot and you now have a very, very dangerous situation.

    The circuit is overloaded but the breaker has not closed because the breaker isn't overloaded.

    I hope that makes sense... Hire a NABCEP certified electrician and use the proper backfeed breakers to feed your solar into your service panel safely! Stop worrying about if you need a permit or not, THERE IS A REASON FOR ELECTRICAL CODES AND PERMITS, it's not some conspiracy to make you pay for something, its an effort to keep homeowners safe and to help them not get ripped off by stupid ideas like this one!
     
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  8. T3slaOwner

    T3slaOwner Member Extraordinaire

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    When you call it a "very, very dangerous situation" is it dangerous enough that the breaker should trip in less than 10 minutes? That's the rating for a 20% overcurrent on a circuit breaker I looked up.
     
  9. iPlug

    iPlug Member

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    The breaker doesn’t trip in the described situation, the wire just overheats and a fire potentially starts.

    “The circuit is overloaded but the breaker has not closed because the breaker isn't overloaded.“
     
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  10. brkaus

    brkaus Well-Known Member

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    Just to be clear - I have no intent to put money in this. I’m trying to better my understanding. And I know someone that is interested so I wanted solid guidance and not my gut feel.
     
  11. Texas-Rich

    Texas-Rich New Member

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    a level of overcurrent tolerance is engineered into electrical design - EXACTLY for things like this. I'm not going to dig through the NEC cuz I'm in bed but If I recall correctly for circuits under 30 AMPS the breaker can go to 120 or 135%.... However, 80% of a circuit is called the safe load FOR A REASON! And I consider any time that a circuit is overloaded a dangerous situation. But then I'm in the biz and after you see toasted electrical panels, fried wiring or worse the remains of a house fire it tends to make me want to always stick to the safe load on any circuit.
     
  12. Ampster

    Ampster Active Member

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    Yes it is a thing in California and possibly in other states. The building codes in California require a permit for any new circuits. The latest National Electrical Code requires Rapid Shut Down. Not all states have adopted the latest NEC. That part has nothing to do with AC versus DC. RSD is required regardless of whether it is AC or DC on your roof.
     
  13. T3slaOwner

    T3slaOwner Member Extraordinaire

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    I don't know if you are responding to me or not. My point is that while the situation was described as a "very, very dangerous situation", without the solar power input, the circuit breaker would take significant time to trip. Circuit breakers in homes are not designed to trip with the slightest fraction of current over the limit because small current overages are not dangerous. The wire heats up in a similar manner to the element in the circuit breaker. At a 20% overload it is pretty much impossible to start a fire unless something is faulty like a connector with a high resistance, which can also start a fire at 20% undercurrent. That's what happened with aluminum wiring. It was installed without consideration of the expansion coefficient mismatch and eventually formed a weak connection resulting in a fire at normal currents.

    I'm not recommending the contraption being described here. I'm just trying to calm the hysterics.
     
  14. T3slaOwner

    T3slaOwner Member Extraordinaire

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    I see my reference to the Edison/Westinghouse rivalry confused you. Ignore that part.

    I was talking about the mounting on the roof. It sounded like that was the part that required permits. If an appliance plugs into an outlet, I'm not sure it requires permits for the electrical. I've never heard of that before. It is the permanent wiring that typically requires permits.
     
  15. T3slaOwner

    T3slaOwner Member Extraordinaire

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    I was responding to the extreme emphasis you were using, "very, very dangerous situation". My point is that while overloading a circuit is not a good idea, it is not automatically a disaster as shown by the long time it takes for a circuit breaker to trip at moderate overloads.

    I find it better to explain how this is a bad idea with a measured voice.

    Everyone hear that? Don't try this at home...
     
  16. Ampster

    Ampster Active Member

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    I am not saying that an appliance requires a permit. I am saying that a solarpanel on a roof may require a permit and further compliance with Rapid shut Down requirements. It depends on the jurisdiction. If you put the panel on a patio cover it may not require a permit or RSD.
     
  17. miimura

    miimura Well-Known Member

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    One good reason that mounting solar panels on a roof requires a permit is that you have to verify structural loading. Mounting a non-trivial number of solar panels on a roof adds a significant load to be supported by the roof structure.

    If you goal is to stick it to the utility, there are many solutions available that don't require utility approval because they are designed to never feed back into the grid. However, if you connect into your home electrical system, it requires a building permit in most jurisdictions. The most common of these systems is basically to set up a off-grid system with a hybrid inverter and a battery bank with the solar directly charging the batteries. Your house is powered from this system and the grid is only used to charge the batteries when they are low. It is commonly called a grid assisted system. Since the grid is only connected to a battery charger, it is impossible for the battery energy (and therefore solar energy) to flow back into the grid.
     
  18. SageBrush

    SageBrush 2020: Drain the Sewer

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    No
     
  19. SageBrush

    SageBrush 2020: Drain the Sewer

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    Your wiring advice sounds right to me, the NABCEP licensure does not logically follow. I am not an electrician of any sort but I know enough to not overload a circuit.
     
  20. Evbwcaer

    Evbwcaer Member

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    The product does include a "Solar Regulator." It senses whether the power is out and if the unit is plugged in at all. While the website does not specifically answer the question about overloading a circuit, it does seem that the Solar Regulator is not dumb. Perhaps it can sense when there is more than 15 amps on the 6-15 circuit and and reduce/eliminate output.
     

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