When a battery pays for itself, when it doesn't, and how the 30% federal credit changes the math on storage.
When it makes sense
You live somewhere with net billing or no net metering, you pay time-of-use rates with a steep on-peak window, or you experience frequent grid outages.
When to skip it
Full-retail net metering plus a stable grid usually means a battery is a resilience purchase, not a savings purchase. Model both scenarios before adding storage.