About 17.7 hours. A 500 Wh power station has roughly 425 Wh usable, and a chest freezer averages about 24 W because the compressor cycles on and off. Depending on the model the range is about 9.4 to 28.3 hours.
- Runtime
- 17.7 hEstimate at average draw
- Usable energy
- 425 Wh85% of 500 Wh
- Average draw
- 24 W80 W while running
- Surge
- 2,200 WCheck the surge rating
The math
| Usable capacity | 500 Wh × 0.85 = 425 Wh |
|---|---|
| Average draw | 80 W running × 0.3 duty = 24 W |
| Runtime | 425 ÷ 24 = 17.7 h |
Things to check
- The power station's surge rating must cover the 2,200 W start-up surge, or it will shut off when the compressor kicks in. Many smaller units can't.
- Food-safety guidance says a closed fridge stays cold about 4 hours and a full freezer about 48 hours, so you can run it in shifts to stretch the battery.
Other battery sizes
Questions people ask
How long will a 500 Wh power station run a chest freezer?
About 17.7 hours (about 17.7 hours). A 500 Wh power station has roughly 425 Wh usable, and a chest freezer averages about 24 W because the compressor cycles on and off. Depending on the model the range is about 9.4 to 28.3 hours.
How many watts does a chest freezer use?
A chest freezer typically draws about 80 watts while running (roughly 50-150 W) and uses about 0.6 kWh a day. The compressor needs a short starting surge, listed as up to about 2,200 watts on generator charts.
How do you calculate power station runtime?
Hours ≈ capacity in Wh × 0.85 ÷ average watts. The 0.85 allows for inverter and battery losses.