Runtime depends on your fridge's real energy use. Here is how to estimate it, with examples for common sizes.
Key takeaways
- Runtime = usable Wh divided by your fridge's daily Wh, times 24 hours.
- A 1,000 Wh unit runs a typical fridge for roughly 10 to 17 hours.
- Keep the door closed and consider cycling the fridge.
Formula: usable watt-hours (capacity x 0.85) divided by the fridge's average daily watt-hours, times 24 hours.
Find your fridge's energy use
Look for the EnerGuide label (Canada) or EnergyGuide label (US), or the manual. Annual use in kWh divided by 365 gives daily kWh. A modern fridge often falls roughly between 1 and 2 kWh per day, but older ones use more.
Worked examples
| Battery | Usable (x0.85) | Fridge at 1.2 kWh/day | Fridge at 2 kWh/day |
|---|---|---|---|
| 500 Wh | 425 Wh | about 8.5 h | about 5 h |
| 1,000 Wh | 850 Wh | about 17 h | about 10 h |
| 2,000 Wh | 1,700 Wh | about 34 h | about 20 h |
| 3,000 Wh | 2,550 Wh | about 51 h | about 31 h |
Make it last longer
- Keep the door closed. A full, cold fridge holds temperature better than an empty one.
- Run it in cycles: unplug for a few hours, then run a few hours. A closed fridge stays cold for roughly four hours, and a full freezer holds for about 48 hours if the door stays shut, according to common food safety guidance. Check your health authority's rules.
- Pair the station with solar panels if you expect multi-day outages.
Check these before you buy
- Rated output must cover the fridge's start-up surge. Look for a surge rating on the station.
- Pure sine wave output is best for compressors.
- Check the maker's page for any warnings about running motors.
Quick comparison
| Brand | Best for |
|---|---|
| EEcoFlow | Fast charging and expandable systems |
| BBLUETTI | Large lineup, expandable home systems |
| JJackery | Wide range, compact to home backup sizes |
E
EcoFlowFast charging and expandable systems
Larger capacity models suit fridge backup.
- Markets fast charging, so compare charge times
- Expandable systems in larger sizes
- Check solar input specs
B
BLUETTILarge lineup, expandable home systems
Higher capacity and expandable options.
- Broad capacity range
- Expandable home-backup options
- Compare battery chemistry and stated cycle life
J
JackeryWide range, compact to home backup sizes
Range that includes 1,000 Wh and above.
- Has a Canadian store
- Small, mid and large models
- Compare capacity, output and warranty on the maker page
Quick answers
How do I find my fridge's energy use?
Check the EnerGuide (Canada) or EnergyGuide (US) label for yearly kWh, then divide by 365.
Will any power station run a fridge?
Only if its rated output covers the compressor's start-up surge. Check the surge rating.
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