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Is plug-in solar coming to the US?
- Thread starter Banjohn
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400bird
Solar Wizard
Wait, legal or illegal?
I'm amazed these could ever be UL listed. With one connected to a circuit you can easily overload said circuit feeding it from both the grid and solar if there's a heavy load (or short) elsewhere...
Sorry, it's legal.
Solar balcony systems are pretty popular in Germany.
The Germans limit the AC output to 800W, and Utah limits the AC output to 1200W.
400bird
Solar Wizard
And household circuits in Germany are commonly 3,680 watts (16a @ 230v)
So, 800 watts is ~20% of the circuits rating, an overload that the circuit will be much more likely to survive.
Vs the Utah spec
Common household breakers are 15 amps (or maybe 20) at 120 volts, so 1800 watts
1,200 watts means you could overload the circuit by 66% if you only plug in a single one.
From the snip provided Utah doesn't limit the quantity of 1200 watt systems.
I'm kind of annoyed they specifically called out a 120 volt outlet as a requirement. Why limit it to a 120 volt outlet? You could plug it into a 240v dryer outlet and have a dedicated circuit that wouldn't be easily overloaded.
I do think this possibly a beneficial product, but plugging it in to a regular wall outlet seems like it could be problematic.
Q-Dog
¯\_(ツ)_/¯
Wouldn't you love to know what company managed to get this through the Utah legislature? I have a guess.
Enphase seems pretty good at manipulating regulations to favor their products.
Doesn't matter, as long as there is a simple way to plug an solar into the grid and reduce bill similar to Germany.
Q-Dog
¯\_(ツ)_/¯
I was thinking more local ... a company headquartered in Utah.
timselectric
If I can do it, you can do it.
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I see an increase in house fires, in Utah's future.
Q-Dog
¯\_(ツ)_/¯
Let's see how many scenarios we can come up with, using this device, that would be dangerous.
One way I can think of would be plugging two high draw appliances into the same outlet, with this device feeding a separate outlet on the same circuit. But what happens if a branch circuit has 3 outlets and each device plus the solar gadget gets it's own outlet? Still dangerous?
timselectric
If I can do it, you can do it.
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The problem is that there are many ways to overload a circuit, with this type of product. And without any protection from it, bad things will happen.
For example.
Someone has a lot of power tools in their garage. They can only use one at a time to avoid tripping the breaker. They hear about this product and realize that the front porch receptacle is on the same breaker. They do some thinking about it. And figure out that 4 of these plug in solar products plugged into the front porch, let's them use all of the power tools in the garage, without tripping the breaker.
And voila, problem solved. (Until the house burns down)
Q-Dog
¯\_(ツ)_/¯
Are we worried about overloading the wiring or the receptacles? The law is written that the device must be UL listed/tested. There must be a way to make it safe to get that UL stamp.
I'm just trying to see how it can work. There was storage device proposed years ago that would plug into the wall. Same concerns came up. As far as I know they are still vaporware.
What if the plug from the solar device blocks the receptacle so nothing else can be plugged into the second outlet in that spot?
timselectric
If I can do it, you can do it.
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The wiring.
Not as a plug-in device. There's nothing stopping someone from using multiple units on a single circuit.
Maybe there's a second outlet on the porch. Or they use an extension cord.
Sorta a worthless rule since there is no approved devices. Likely will cause all kind of folks to buy the cheap microinverters (found on Amazon, Ebay, Aliexpress) though and plug them in thinking it is OK. It might even increase the folks that think a suicide cord for their generator is a good idea. All in all just a badly thought out rule change.
It seems to not be any use for the zero export crowd either since the utility company will likely still send someone out to check spurious export and demand for proof of device being an approved one.
It seems to not be any use for the zero export crowd either since the utility company will likely still send someone out to check spurious export and demand for proof of device being an approved one.
Hedges
I See Electromagnetic Fields!
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If it shuts off in 1/2 cycle because it doesn't see any voltage present, no harm no foul - same as GFCI.
My Sunny Island battery inverter takes 1/2 second. Not sure how fast Sunny Boy GT PV inverter is.
20A house circuits are wire with 12 awg which has 30A ampacity. 15A with 14 awg which has 25A ampacity (at 90 degrees C.)
So one 1200W 10A backfeed would not severely overload it. Two would.
My Sunny Island battery inverter takes 1/2 second. Not sure how fast Sunny Boy GT PV inverter is.
20A house circuits are wire with 12 awg which has 30A ampacity. 15A with 14 awg which has 25A ampacity (at 90 degrees C.)
So one 1200W 10A backfeed would not severely overload it. Two would.
RCinFLA
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That does not comply with the newer ride-through regulations.
Utilities do not like that and will argue that as population of devices grows it puts the public utility grid at risk of damage.
Strange, that means utilities in Germany must have done something right to allow such devices into their grid.
Hedges
I See Electromagnetic Fields!
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Ride-through only for moderate voltage or frequency deviation.
Disconnect in 1 second for excessively low voltage, 0.02 second for excessively high voltage, 0.1 second for excessively low or high frequency.
solarbuildermag.com
So that could require 0.1 second if unplugged, still several times too long for human safety.
@RCinFLA is correct this seems to have safety hazard.
Disconnect in 1 second for excessively low voltage, 0.02 second for excessively high voltage, 0.1 second for excessively low or high frequency.
How California’s Rule 21 inverter requirements expand grid capacity, limit energy (revenue) generation
A multi-year effort has been ongoing in California to update technical requirements for connecting Distributed Energy Resources (DER) to the grid, known as Rule 21. The experience of Germany was... View Article
solarbuildermag.com
So that could require 0.1 second if unplugged, still several times too long for human safety.
@RCinFLA is correct this seems to have safety hazard.
Zwy
Emperor Of Solar
I read your other response but 1200W is 10A on a 120V outlet. Probably why it limits output to 1200W. On a 15A circuit, it still would be difficult to overload the 14AWG wire before the unit shuts down or trips a breaker in it.
SkyBlue
New Member
I don't believe Utah's HB 340 (2025) has passed the state's legislature and been signed into law yet. And if Utah's for profit utility corporations are anything like California's they will kill the bill before it clears the first house.
400bird
Solar Wizard
robbob2112
Doing more research, mosty harmless
Uhm, if the circuit is getting 10 amps from solar and 15 from grid... it is getting 5 from grid on balance...
Think it through and there is no case where you can exceed an outlet and circuit capacity... if there is heavy demand it gets used right up
Ok, there is one way.... 10 amps from solar and a shorted wire and 15 amps from grid....so 25amps for a split second and the breaker trips... then the solar cuts out because there is no grid
Think it through and there is no case where you can exceed an outlet and circuit capacity... if there is heavy demand it gets used right up
Ok, there is one way.... 10 amps from solar and a shorted wire and 15 amps from grid....so 25amps for a split second and the breaker trips... then the solar cuts out because there is no grid
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