We used roughly 10MWh of electricity last year (house + RAV4 Prime). 47% of that (4.7MWh) came from solar directly. 39% (3.9MWh) came from the Powerwalls. 14% (1.4MWh) came from the grid. That's slightly better than last year when we imported 15% of our electricity from the grid. In 2021 we only imported 9% of our power, but we bought the RAV4 Prime in the latter half of 2021.

We imported 1.5MWh of electricity from FPL. 7% of that (97.4kWh) went to charging the Powerwall(s) during Storm Watch events, later consumed by the house. We exported 2.3MWh of power to the grid when the Powerwalls were fully charged and we weren't consuming all we were producing.

Net, we exported more power than we imported, 783.7kWh to the grid.

We generate more power than we consume overall. But because of weather and seasonal daylight variations and battery capacity, we can't cover all of our requirements all the time by solar and battery storage alone.

86% self-sufficient seems pretty good to me. When we installed the system, we didn't factor in acquiring a plug-in hybrid, and we've added additional load with the mini-split AC in the garage. As these batteries age, their capacity diminishes (~2.5%/year) When they get down to about 75% capacity in about six or seven years, I'll look at adding an additional battery, rather than wholesale replacement. Hopefully that doesn't pose any insurmountable technical hurdles.

10 years after that, I'll be in my 80s if I'm still alive. I suspect I may be beyond caring at that point.

Here's another solar+battery blogger who has a much larger array but only one battery.