About 20.2 hours. A 500 Wh power station has roughly 425 Wh usable, and a portable 12V fridge averages about 21 W because the compressor cycles on and off. Depending on the model the range is about 10.1 to 28.9 hours.
- Runtime
- 20.2 hEstimate at average draw
- Usable energy
- 425 Wh85% of 500 Wh
- Average draw
- 21 W50 W while running
- Surge
- NoneNo motor start
The math
| Usable capacity | 500 Wh × 0.85 = 425 Wh |
|---|---|
| Average draw | 50 W running × 0.42 duty = 21 W |
| Runtime | 425 ÷ 21 = 20.2 h |
Other battery sizes
Questions people ask
How long will a 500 Wh power station run a portable 12V fridge?
About 20.2 hours (about 20.2 hours). A 500 Wh power station has roughly 425 Wh usable, and a portable 12V fridge averages about 21 W because the compressor cycles on and off. Depending on the model the range is about 10.1 to 28.9 hours.
How many watts does a portable 12V fridge use?
A 12 V compressor fridge/cooler draws about 50 watts while the compressor runs (roughly 35-100 W) and averages about 0.5 kWh a day (around 20 W average) as it cycles in mild weather.
How do you calculate power station runtime?
Hours ≈ capacity in Wh × 0.85 ÷ average watts. The 0.85 allows for inverter and battery losses.