Evidence page
Portable power station for a refrigerator
Short answer: for a typical US refrigerator drawing 1,000–1,900 Wh per day, a 1,000 Wh station covers most of one day and a 2,000 Wh station covers one to two days. Anything longer needs daily recharge — and no size works at all if the station cannot start the compressor.
Last updated 8 August 2026
Usable energy, not nameplate energy
A station’s advertised watt-hours are the pack, not what reaches your refrigerator. Applying an 85% AC delivery factor and holding back a 15% safety reserve leaves about 72% of the label. Every row below is computed that way.
| Nameplate | Planning energy | What that means for a refrigerator |
|---|---|---|
| 500 Wh | ~360 usable Wh | About 4–9 hours. A short outage only, and small inverters may fail the compressor surge. |
| 1,000 Wh | ~720 usable Wh | About 9–18 hours. Covers most of one day for a typical refrigerator. |
| 2,000 Wh | ~1,440 usable Wh | About 18–36 hours. One day comfortably; two days only for an efficient unit. |
| 3,000 Wh+ | ~2,160 usable Wh | Roughly one to two days. Past 48 hours, daily recharge decides the answer, not capacity. |
The gate most size charts skip
Two watt figures decide compatibility, and neither can be derived from watt-hours. The steady running watts must sit inside the station’s continuous output with margin, and the startup surge must be inside what the inverter can actually deliver — not the marketing surge number. If either is unknown, the honest output is “energy sized, compatibility unproven”, which is exactly what the diagnostic on this site returns.
Where a portable station stops being the answer
- Multi-day outages with no realistic daily recharge.
- A required automatic switchover that the unit cannot prove.
- A refrigerator plus a separate freezer plus medical equipment on one pack.
In those cases the correct verdict is abstention or an installed system, and adding watt-hours does not change it.
Get your own answer
Run the refrigerator check with your EnergyGuide figure, or read the underlying refrigerator backup arithmetic. Prices and runtime promises are deliberately absent from this page.