Power station runtime calculator (hours)

Updated 3 Nov 2026. Enter your power station's capacity and what you're running to estimate how many hours it will last. Runs in your browser.

How it works

Hours = capacity (Wh) × efficiency ÷ load (W). AC inverters typically lose about 10-20% as heat, so 85% is a sensible default. Cycling loads like fridges draw less on average than their rated watts, so use the average draw if you know it. Cold weather and battery age reduce usable capacity.

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