About 1.1 hours. A 500 Wh power station has roughly 425 Wh usable, and a window air conditioner averages about 396 W because the compressor cycles on and off. Depending on the model the range is about 0.6 to 1.6 hours.
- Runtime
- 1.1 hEstimate at average draw
- Usable energy
- 425 Wh85% of 500 Wh
- Average draw
- 396 W660 W while running
- Surge
- 1,500 WCheck the surge rating
The math
| Usable capacity | 500 Wh × 0.85 = 425 Wh |
|---|---|
| Average draw | 660 W running × 0.6 duty = 396 W |
| Runtime | 425 ÷ 396 = 1.1 h |
Things to check
- The power station's surge rating must cover the 1,500 W start-up surge, or it will shut off when the compressor kicks in. Many smaller units can't.
- Air conditioners draw heavily; a battery alone runs one for hours, not days. A generator or solar recharging is the long-term answer.
Other battery sizes
Questions people ask
How long will a 500 Wh power station run a window air conditioner?
About 1.1 hours (about 1.1 hours). A 500 Wh power station has roughly 425 Wh usable, and a window air conditioner averages about 396 W because the compressor cycles on and off. Depending on the model the range is about 0.6 to 1.6 hours.
How many watts does a window air conditioner use?
An 8,000 BTU window air conditioner uses about 660 watts. Common sizes run from about 440 W (5,000 BTU) to 1,100-1,200 W (12,000 BTU), and the compressor needs roughly 1,500 watts for a moment to start.
How do you calculate power station runtime?
Hours ≈ capacity in Wh × 0.85 ÷ average watts. The 0.85 allows for inverter and battery losses.
Sources
- GE AEM08LX 8,000 BTU window AC specifications (660 W, CEER 12.0)
- LG LW5016 5,000 BTU window AC specifications (440 W, CEER 11.0)
- Frigidaire FHWW122WC 12,000 BTU window AC spec sheet (1,100 W)
- ENERGY STAR: Room air conditioners
- ENERGY STAR: Room air conditioner key product criteria (CEER)
- Honda Power Equipment Canada: Generators guide, appliance running and starting watts