Battery Size Estimator
Estimate a practical starting battery size.
This estimator is designed to answer the question most homeowners actually have first: what battery size band should I even be looking at before I compare brands or chemistry?
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How to use this battery-sizing tool well
What this tool helps with
Use it to get into the right battery size band before comparing brands, chemistry, or installer quotes.
If you do not know your evening kWh
Use the household estimate mode as a shortlist tool only. It is useful for narrowing the search, but real evening import data is still better before buying.
How to read the result
Read the output as a starting size band, not as a precise product recommendation. Backup scope, inverter path, and staged expansion can still move the final system design.
What pushes battery size up fastest
Backup scope is usually the first real size multiplier
A battery sized only for bill shifting is often much smaller than one sized to keep more circuits running through an outage.
If you do not know your evening kWh, use the estimate as a starting band only
The household profile route is meant to stop people getting stuck. It is useful for a shortlist, but real interval data is still better before buying.
Evening imports matter more than total daily usage
For most households, the battery is mainly covering what happens after solar production fades. That is why evening demand is a better starting input than whole-day consumption.
Chasing every last exported kWh can oversize the system
If the goal is simply to use more solar at home, there is usually a point where moving from a solid battery band to a much larger one produces weaker returns.