Calculator

Battery Backup Runtime Calculator

By NerdVolt Editorial TeamJune 16, 2026Estimate tool

Accuracy note: The arithmetic on this page is deterministic from your inputs. Solar production, code, utility, incentive, and savings outputs are estimates unless you supply exact equipment specs, tariffs, shade data, and local requirements.

Inputs

Result

How this is calculated

Load kWh = watts × hours ÷ 1000. Usable AC kWh = battery kWh × DoD × inverter efficiency. Runtime = usable AC kWh ÷ load kW.

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