utilities
Inverter Battery Backup Calculator
Estimate usable battery energy and backup time for a connected load.
Estimated backup
7.2 h
Usable energy
3.6 kWh
Nominal energy
4.8 kWh
How this works
Backup hours = volts × amp-hours × usable efficiency ÷ load watts.
Worked example
A 24 V, 200 Ah bank at 75% usable efficiency supports 500 W for about 7.2 hours.
FAQ
What is the Inverter Battery Backup Calculator used for?
Estimate usable battery energy and backup time for a connected load. It is intended for quick planning, checking, and everyday decisions.
Can I use the result for a final contract or design?
Use it as a planning estimate. Battery chemistry, discharge rate, age, inverter surge, temperature, and reserve settings reduce real backup.
How can I improve the accuracy?
Use measured quantities, current supplier or lender rates, the correct units, and compare the result with drawings, invoices, or professional advice where the decision is safety-critical.