Short answer: almost any modern power station of about 1,000 Wh or more can start a typical home refrigerator, because every model we track that publishes a surge rating lists 2,700 W or more. What really matters is capacity. A fridge that uses 600 kWh a year needs a battery that can supply roughly 1,900 Wh per day once you account for inverter losses. That means a ~1 kWh unit covers about half a day, a ~2 kWh unit about a day, and a ~3.6–4 kWh unit about two days.
The rest of this guide shows the math so you can plug in your fridge’s numbers. You can also skip straight to the runtime calculator.
Why your fridge matters first
Refrigerated food has a short clock. FoodSafety.gov (citing USDA) says your refrigerator will keep food safe for up to 4 hours during an outage if you keep the door closed, and a full freezer holds a safe temperature for about 48 hours (24 hours if half full) (FoodSafety.gov). Perishables that sit above 40°F for more than 2 hours should be thrown out. That’s why the fridge is the first appliance most people size a backup around.
Step 1: Can the power station start the fridge? (surge watts)
A refrigerator compressor is a motor. Motors draw a burst of extra power for a moment when they start.
- Champion Power Equipment’s generator chart lists a typical refrigerator at 150–400 W running and 800–1,200 W starting (Champion).
- Honda’s sizing example uses 200 W running and 1,600 W starting for a refrigerator (Honda).
Typical estimates vary, so we’d plan for a startup surge of at least 1,600 W, plus whatever else is running when the compressor kicks on. Here’s how the eight models in our dataset compare. Every one lists a surge rating well above that, except the Anker SOLIX F3800 Plus, whose spec page lists 6,000 W of output but no separate surge figure.
| Model | AC rated | AC surge (as published) |
|---|---|---|
| BLUETTI AC180 | 1,800 W | 2,700 W |
| Jackery Explorer 1000 v2 | 1,500 W | 3,000 W |
| Anker SOLIX C1000 Gen 2 | 2,000 W | 3,000 W |
| EcoFlow DELTA 3 Plus | 1,800 W | 3,600 W |
| Jackery Explorer 2000 v2 | 2,200 W | 4,400 W |
| Jackery HomePower 3600 Plus | 3,600 W | 7,200 W |
| Anker SOLIX F3800 Plus | 6,000 W | not listed |
| EcoFlow DELTA Pro 3 | 4,000 W | 8,000 W |
Sources: each model’s official page, checked October 7, 2026 (links in the table below and in our cost per kWh comparison).
Check your own fridge. The nameplate (usually inside the door or on the back) lists volts and amps; volts × amps gives a worst-case wattage. Older fridges, side-by-sides, and models with ice makers tend to sit higher.
Step 2: How much energy does the fridge use per day?
This is where most online guesses go wrong. A fridge doesn’t draw its running wattage all day, because the compressor cycles on and off. The best number you have is the yellow EnergyGuide label, which lists estimated kWh per year.
The 0.85 is our stated assumption for inverter efficiency (converting battery DC to AC for your outlet). See our methodology.
| EnergyGuide label | Daily use | Average draw | Battery needed per day |
|---|---|---|---|
| 400 kWh/yr | ~1,096 Wh | ~46 W | ~1,289 Wh |
| 600 kWh/yr | ~1,644 Wh | ~69 W | ~1,934 Wh |
| 800 kWh/yr | ~2,192 Wh | ~91 W | ~2,579 Wh |
These are worked examples, not claims about any specific fridge. Use your own label. ENERGY STAR notes that certified refrigerators are about 9% more efficient than the federal minimum, that the most efficient models are typically 16–20 cubic feet, and that top-freezer models tend to use the least energy (ENERGY STAR). In real outages, your fridge’s consumption also depends on room temperature and how often the door opens.
No label? The calculator’s default (275 W running, compressor on about a third of the time) works out to roughly 2,200 Wh per day. That’s deliberately on the high side.
Step 3: Estimated runtime by power station
Using the middle example above (a fridge rated at 600 kWh/yr):
| Model | Rated capacity | AC rated / surge | Estimated runtime |
|---|---|---|---|
| EcoFlow DELTA 3 Plus | 1,024 Wh | 1,800 W / 3,600 W | ~13 hours |
| Anker SOLIX C1000 Gen 2 | 1,024 Wh | 2,000 W / 3,000 W | ~13 hours |
| Jackery Explorer 1000 v2 | 1,070 Wh | 1,500 W / 3,000 W | ~13 hours |
| BLUETTI AC180 | 1,152 Wh | 1,800 W / 2,700 W | ~14 hours |
| Jackery Explorer 2000 v2 | 2,042 Wh | 2,200 W / 4,400 W | ~25 hours |
| Jackery HomePower 3600 Plus | 3,584 Wh | 3,600 W / 7,200 W | ~44 hours |
| Anker SOLIX F3800 Plus | 3,840 Wh | 6,000 W / not listed | ~48 hours |
| EcoFlow DELTA Pro 3 | 4,096 Wh | 4,000 W / 8,000 W | 2.1 days (~51 h) |
For a more efficient 400 kWh/yr fridge, the 1 kWh-class units stretch to roughly 19–21 hours. For an 800 kWh/yr fridge, they drop to roughly 9.5–11 hours. Add a freezer, router, lights, or a CPAP and these runtimes shrink, which is exactly what the runtime calculator is for.
Which size makes sense?
- Short outages (an evening or overnight): a ~1 kWh unit is usually enough to keep the fridge cold with some left over for phones and a router. Examples in our data: Jackery Explorer 1000 v2, BLUETTI AC180, EcoFlow DELTA 3 Plus, Anker SOLIX C1000 Gen 2.
- About a day without recharging: ~2 kWh, such as the Jackery Explorer 2000 v2.
- Multi-day outages, or a fridge plus other essentials: ~3.6 kWh and up, or a smaller unit you can recharge from solar or a generator. Examples: Jackery HomePower 3600 Plus, Anker SOLIX F3800 Plus, EcoFlow DELTA Pro 3.
If a unit can be recharged during the day (solar, a car, or a generator), you can buy less capacity than the multi-day math suggests. See our solar compatibility explainer.
Practical tips
- Keep the doors closed. FoodSafety.gov and Ready.gov both say this first. ENERGY STAR also lists minimizing door openings as a way to cut fridge energy use.
- Use a thermometer. Ready.gov recommends monitoring temperatures and throwing out food at 40°F or higher (Ready.gov).
- Plug the fridge directly into the power station’s AC outlet with a properly rated cord, and follow the power station’s manual.
- Medicines that need refrigeration: Ready.gov advises having an alternate plan and asking your provider or pharmacist (Ready.gov).
Sources
- FoodSafety.gov, Food Safety During Power Outage (checked Oct 7, 2026)
- Ready.gov, Power Outages (checked Oct 7, 2026)
- Champion Power Equipment, Generator Wattage Chart (checked Oct 7, 2026)
- Honda Power Equipment, What Size Generator Do I Need? (checked Oct 7, 2026)
- ENERGY STAR, Refrigerators (checked Oct 7, 2026)
- Power station specs: EcoFlow DELTA 3 Plus, EcoFlow DELTA Pro 3, Jackery Explorer 1000 v2, Jackery Explorer 2000 v2, Jackery HomePower 3600 Plus, BLUETTI AC180, Anker SOLIX C1000 Gen 2, Anker SOLIX F3800 Plus (all checked Oct 7, 2026)