The great thing about solar is that you just sort of forget about it. With the system being 11 years old, I don't often think about it. My system is not large enough to power all my house, so it just generally lowers my bill each month based on sunlight. Instead of worrying about battery power, I just push excess power to the grid and get a credit against power I'm using later. Per the battery, my basic math says the systems can't come close to paying for themselves. If you decide on a battery, its for the backup, not a financial decision. Best I can tell, the Tesla Powerwall costs $10,500 USD installed. It can hold 14 Kwh of electricity. My rates are approximately $0.10 per Kwh. Assuming I could completely charge/discharge the battery each day, I could save (assuming I didn't get credit for the power pushed to the grid) $1.40 per day. 10,500 / 1.4 = 7,500 days to break even. So about 20.5 years of perfect charge discharge each day. I doubt it would last that long at full charge/discharge. This would require a significant power price difference, so I'll keep being grid tied :) [One Year of Solar Power – Snorkie](https://snorkie.com/one-year-of-solar-power/)
Hogan