About Battery Autonomy Calculator
Battery autonomy is the time a battery can run a load before it reaches its discharge limit. Stored energy is capacity × voltage in watt-hours. Only part of it is usable: multiply by the allowed depth of discharge, then by the efficiency of the inverter and wiring, and divide by the load in watts. Hours = Ah × V × DoD × efficiency ÷ W. Real runtime is shorter at high discharge currents and low temperatures.
How to use Battery Autonomy Calculator
- Fill in "Battery capacity", "Battery voltage", "Load" and "Usable depth of discharge", and the other options.
- The result appears below and updates as you type.
- Copy the result with the copy button, or download it as a file where that is offered.
Questions about Battery Autonomy Calculator
What depth of discharge should I use?
A common planning figure is 50 percent for lead-acid batteries and 80 to 90 percent for lithium iron phosphate, because deeper discharge shortens battery life. Use the limit stated by the manufacturer of your battery if you have it.
Runs in your browser. Page last updated .