I’m not sure I understand how this works unless you split off loads into a subpanel that is fed by a UPS which is fed by solar panels, and also isolated from your utility connected electrical service.
As far as I understand it, you can’t have power generated by solar panels feeding loads in your grid-connected panel without backfeeding the grid, same deal as a generator backfeeding a grid-connected panel. You have to kill the MCB or service disconnect to prevent backfeeding.
If you have links with info on how this work (one-line diagram would be extremely useful) I’d be curious. I sell and run commercial electrical work, FWIW. I’ve done zero solar jobs so my understanding could definitely be wrong!
Grid < Primary solar > Battery < Secondary Solar
Where the house is powered by inverter directly on the battery (and maybe a second inverter for primary solar to grid?)
https://knowledge-center.solaredge.com/sites/kc/files/feed-i...
An inverter can limit its output, right? So measure current at a few different points in the system, do some math, and use that to set the inverter's limit.
Here is one example code from Arizona [https://law.justia.com/codes/arizona/title-9/section-9-467/].
And a lot of unclear discussion [https://www.reddit.com/r/phoenix/comments/4ugdtu/is_it_illeg...]
At a state level they’ve been making it clearer that it is technically legal - but it’s still hard to actually do.
There has been a lot of controversy on this topic, with permits getting denied in cities when the plan was to be off grid (and people just caving), and some utilities explicitly raising connection fees to ensure zero-usage customers were still paying them.
It gets people really angry too of course (at least in the US) because ‘what do you mean big government won’t let me do what I want on my own land!’.
The reality is, the types of folks who actually want to go truly off grid (and don’t feel the need/prioritize the backups provided by an optional grid connection, or think it is too expensive) probably already live far enough in the boonies that building codes are largely optional anyway.
It’s pretty rare that a random city dweller is going to be trying to go 100% off grid in their condo, or would have the physical space or legal ability to do so, regardless of what the city says.
And code enforcement looking too closely at things way out in the sticks tends to find itself in some very dangerous situations - the type people just disappear from sometimes and are never found - especially out in the remote parts of America’s deserts/woods.