How long will a power station run a refrigerator?
A fridge is one of the most common things people want to keep running in an outage. It is also easy to misjudge, because the watts on the label are not what it uses on average. A compressor cycles on and off, so a full-size fridge rated at 150 W often averages around 50 W over a day.
All runtimes assume 87% inverter efficiency and are estimates. Your real results depend on your devices, the battery’s age and the temperature.
| Battery size | Mini fridge (~24 W avg) | Full-size fridge (~52 W avg) | Chest freezer (~35 W avg) |
|---|---|---|---|
| 300 Wh | about 11 hours | about 5 hours | about 7 hours |
| 500 Wh | about 18 hours | about 8 hours | about 12 hours |
| 1,000 Wh | about 36 hours | about 16 hours | about 25 hours |
| 2,000 Wh | about 72 hours | about 33 hours | about 50 hours |
Check the startup surge
When the compressor starts, a fridge can briefly draw two to four times its running watts. A full-size fridge may spike to around 600 W. Your power station’s inverter has to handle that spike, not just the average, or it will shut off.
Ways to make it last longer
- Chill the fridge and freezer fully before the outage and keep doors closed as much as possible.
- Fill empty space with jugs of water. Cold mass helps the compressor rest longer.
- Keep the fridge out of direct sun and away from heat sources. A warm room makes the compressor run more often.
- Run the fridge only part of the time. A closed fridge generally keeps food safe for about four hours without power, according to USDA guidance, so you can power it in cycles instead of continuously.