Bill reduction is not the same as production. Understanding the difference is what keeps expectations aligned with reality after your system turns on.
Offset versus elimination
Even a well-sized system typically leaves a minimum delivery charge and any non-bypassable fees on the account. A solar bill is usually smaller, not absent.
Under current California rules, what you are paid for energy exported to the grid differs from what you pay to import it, which is why the timing of your usage matters so much.
Where a battery changes the math
If most of your usage happens in the evening, storing midday production and using it after sunset can matter more than adding panels. That is a usage-shape question, and it is specific to your household.
Related services
Solar production, bill offset and payment comparisons vary by home, usage, roof, shading, utility rate schedule and financing terms. Nothing on this site is a guarantee of savings. Pricing comparisons depend on system size, equipment, financing structure and contract terms. Any comparison is only meaningful between comparable systems and comparable financing.