You can't normally go fully off grid in CA. You're legally required to be on grid to be habitable, outside of special cases, and depending on the area you're in. That means even if you had a billion panels and a zillion batteries, you must be connected to the grid as well, again outside of pretty abnormal situations.
Exact details of what I said there are maybe a bit off, but you are required to be connected to the grid. That's why the recent solar laws and upcoming ones are so egregious. You're legally required to be connected, and you're required to pay these minimum fees, which are soon going to be income based. You're basically legally required to pay PGE monthly even if you don't need them.
Regarding the circuit being off grid, I don't think there's a situation that'd end up being optimal. If you over produce, you'd be better off using that solar for something else or selling it to PGE. If you under produce, you need power from somewhere else, and the grid is great for that.
Best bet if you only wanted to power your system from your panels would be install a Home Assistant device connected to your panels and smart plugs, and dynamically turn off lights and such based on how much power your panels are generating. I'm not sure that'd be a great idea, but definitely doable.
Edit: btw by off grid I mean actually disconnected. Off grid meaning you have enough panels and batteries to power your place is a different matter.
Edit 2: I did a bit more research to double check my info and found there are ways, very expensive ways, to get around this, depending on your area. Still basically never going to be the ideal setup unless you're in a special situation.