Power station for a window AC: size and runtime
Air conditioning is the most demanding thing most people ask a portable station to do. An 8,000 BTU window unit is feasible for a few hours; do not expect a small station to cool a room overnight.
Typical numbers
| Item | Typical running | Typical start-up surge |
|---|---|---|
| Window AC, 8,000 BTU | 700 W | about 2,000 W |
Typical values, assuming the compressor runs about half the time (average about 350 W). Hot days push it toward continuous running; check the label for your unit's watts or amps. Larger units draw more.
Worked example
With 85% of rated capacity usable and an average draw of 350 W:
| Battery rating | Usable | AC runtime |
|---|---|---|
| 1,000 Wh | 850 Wh | about 2.4 hours |
| 2,000 Wh | 1,700 Wh | about 4.9 hours |
| 3,000 Wh | 2,550 Wh | about 7.3 hours |
A full 8 hours at this duty needs about 2,800 Wh. If the unit runs nonstop at 700 W, halve the runtimes.
Good to know
- Check the station's surge rating against about 2,000 W, and its continuous output against 700 W or more.
- Cool one small room, close doors and use a fan to stretch the battery. A fan alone uses about 60 W.
- Inverter-type window units can draw less and start more gently; read the label.
Open the calculator with a window AC filled in
Appliance figures are typical values, not measurements of your device: the label or a plug-in watt meter on yours wins. The sums assume 85% of a battery's rated capacity reaches your outlets (how the numbers work). We list no prices and have not hands-on tested any product.
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