Battery Charge-Time & Surplus Planner
Estimate energy needed and charge time from usable capacity, starting and target state of charge, surplus power and entered efficiency.
Inputs
View resultLive result
Edit inputsEnergy stored
7.0kWh
Input energy
7.8kWh
Charge time
2.6hours
Actual power can taper or be constrained by equipment, temperature, operating mode and site load.
- Estimate energy needed and charge time from usable capacity, starting and target state of charge, surplus power and entered efficiency.
- What you get: Energy required · input energy · indicative charge time.
- Runs in your browser with no sign-up. Saving a result is optional. An estimate for guidance, not a certificate.
How it works
The worksheet finds the change in stored energy between the entered states of charge, divides by entered efficiency to estimate input energy, then divides by average charging surplus. It cannot predict tapering or product controls.
Estimates only: for guidance, not a quote or a compliance certificate. Verify against the current AS/NZS standards and a licensed design. The maths runs in your browser. Nothing is sent to Wattbench unless you sign in and deliberately save the result.
Source ledger1 source
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