I think the inverter is always running in between the batteries and the AC outlets. It's a dedicated "solar circuit".

I have questions. What's the point of a dedicated solar circuit? They are leasing from their "local lines company". If the lines company is in the leasing business, this system must be grid-tied right? Why the dedicated solar circuit?

Also, is it common for full sine wave inverters to produce power less clean than the grid? Maybe when the batteries are low? Curious.