Estimate runtime from usable energy, not the label alone
Interactive planning tool
No signupBattery runtime calculator
Estimated runtime—
Delivered energy—
Runtime changes as loads cycle. This estimate does not validate battery power/current limits or motor-starting surge.
The basic relationship
Estimated runtime is roughly usable delivered energy divided by average load. Melnti’s calculator applies the entered depth-of-discharge percentage and conversion efficiency before dividing by load.
What this estimate does not capture
- Battery power/current limits
- Inverter idle consumption
- Changing loads through the outage
- Temperature-related capacity changes
- Battery reserve settings
- Battery ageing and state of health
- Short-duration surge loads
A battery may have enough energy for the calculated hours yet still be unable to support a high instantaneous load. Always compare both kWh and kW.