My utility tracks usage and generation (the amount I send back to the grid). On my bill they subtract the generation from my total usage to come up with a new total usage and then bill me on that.
My house will will sometimes use directly from the solar as it is being generated. What it doesn’t use will get sent to the grid.
This typically happens in the middle of the day.
I am working on putting together a spreadsheet that shows what my utility says I used on a given day, and what my solar app says I imported, produced, consumed, exported, and net imported.
We’ll see what trends come from that.