How Long Will a 1,000Wh Power Station Run a Refrigerator?

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A 1,000Wh power station runs a full-size refrigerator for roughly 11 to 18 hours. That range comes from the rated yearly energy use of three current ENERGY STAR full-size models, from a 21.8 cubic foot top-freezer to a 23.4 cubic foot bottom-freezer with an ice maker, and an assumption that 85% of the battery’s energy reaches the fridge. The top-freezer without an ice maker sits at the long end, the 23.4 cubic foot bottom-freezer with an ice maker at the short end, and the largest of the three, a 27.4 cubic foot side-by-side, in the middle, so size alone does not decide it. For most full-size fridges, 1,000Wh will not cover a full day without recharging.

This guide is based on published ratings and our own arithmetic. We have not tested any refrigerator or power station. Every runtime below is a calculation you can repeat with your own fridge’s numbers.

How long will a 1,000Wh power station run a refrigerator? The calculation

A fridge does not draw the same power all day. The compressor switches on and off, so the useful number is its average draw. The easiest way to get it is the fridge’s rated annual energy use, which ENERGY STAR publishes for every certified model in its certified refrigerator dataset, and many fridge makers list it on the spec sheet.

1. Average watts = rated kWh per year × 1,000 ÷ 8,760 hours in a year.
2. Usable energy = station capacity in Wh × 0.85. The 0.85 is our planning allowance for inverter losses and a small reserve. It is an assumption, not a figure any manufacturer publishes for these models.
3. Hours = usable energy ÷ average watts.

Three real fridges compared

The same steps give about 13.6 hours for a 27.4 cubic foot side-by-side and about 11.1 hours for a 23.4 cubic foot bottom-freezer with an ice maker. The table shows all three, and the same fridges on two real stations in the 1,000Wh class.

The rated figure comes from a standard test, not your kitchen. A warm room, a full load of warm groceries and frequent door openings all push real use up, so treat these hours as a best case for that model and plan some margin.

Check your own fridge in two minutes

1. Find your fridge's rated kWh-per-year figure: search your model number in the ENERGY STAR dataset or check the maker's spec sheet.
2. Divide it by 8.76 to get average watts (the same as × 1,000 ÷ 8,760).
3. Multiply your station's capacity by 0.85 and divide by that average.

Example: a rating of 600 kWh per year gives 600 ÷ 8.76 = 68.5 W. On a 1,000Wh station that is 850 ÷ 68.5 = about 12.4 hours.

If you only know the fridge's running watts and how much of each hour the compressor runs, the method is the same: average watts = running watts × the fraction of time it runs. The rated annual figure is easier because that cycling is already built in.

How the makers' own estimates compare

Two power station makers publish a fridge runtime for their 1,000Wh-class models. EcoFlow lists "Fridge 7-14 hr" for the 1,024Wh DELTA 3 Plus. BLUETTI lists "Refrigerator 17 Hrs" for the 1,152Wh AC180. Neither page says which fridge or what draw it assumed, so these figures can't be checked line by line. Both overlap the 11 to 21 hour span in our table, which is a useful sanity check: a 1,000Wh-class station is roughly a half-day to one-day fridge battery, not a multi-day one.

Starting the compressor: the other check

Runtime is only half the question. The station also has to start the compressor. Motors draw a short burst of extra power as they start, and the station's surge (peak) rating has to cover it. Our explainer on continuous vs surge watts covers how to compare the two.

ENERGY STAR records do not list starting watts, and we found no fridge maker publishing one for these models. So use two practical checks:

• Running check: the fridge's nameplate amps × 120 V gives an upper-bound figure in volt-amperes. It should sit well below the station's continuous rating.
• Start check: with the station charged and unplugged from the wall, plug the fridge in and let the compressor start several times. If the station shuts off with an overload, that pairing fails.

Do not count on boost modes for this. EcoFlow's DELTA 3 Plus user manual describes X-Boost as more suitable for heating devices. BLUETTI's AC180 page describes Power Lifting Mode as being for high-power heating devices. Use the published surge rating, not the boost figure. On the AC180 the two numbers happen to match: its Power Lifting figure and its published surge rating are both 2,700 W, but only the surge rating applies to starting a compressor.

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Covering a longer outage

If you need the fridge through a full day or longer, work backwards from the hours you need: Wh needed = average watts × hours ÷ 0.85.

Even the most efficient of the three needs about 1.3 kWh for one day. You can get there two ways:

• Add capacity. EcoFlow says the DELTA 3 Plus is expandable up to 5kWh and that its 1kWh DELTA 3 Extra Battery brings it to 2kWh. At 2,048 Wh, the side-by-side example runs about 2,048 × 0.85 ÷ 62.3 = 27.9 hours. The C1000 Gen 2 cannot be expanded, according to Anker's FAQ.
• Recharge during the outage. Solar can top the battery up during the day. Our guide to how many solar panels it takes to charge a power station shows the method, and the solar input vs battery capacity guide shows how to balance the two for a daily load like a fridge.

Planning for a multi-day winter outage with a fridge, furnace and other essentials is a bigger job. Our Canadian winter outage guide works through a full 72-hour budget.

Ways to stretch the runtime

• Keep the doors shut. Every opening lets cold air out, and the compressor has to make it up.
• Run only the fridge. Anything else plugged in shares the same watt-hours.
• Turn off outputs you are not using. A switched-on USB or DC output with nothing useful attached still takes a little from the same battery.
• Charge to full before a storm. Every percent you start below 100 comes straight off the hours in the table.

Which 1,000Wh-class station fits a fridge

All three stations in the output table have continuous ratings far above the average draw of any of these fridges, so the deciding factors are capacity, starting headroom and whether you can expand.

• Most hours on one charge: BLUETTI AC180. Its 1,152 Wh gives the longest runtime of the three, about 12.7 to 21.3 hours across the example fridges. Its 2,700 W surge rating is the lowest of the three, so run the start check with your own fridge.
• Most starting headroom and room to grow: EcoFlow DELTA 3 Plus. It has the highest published surge figure here (3,600 W) and is the only one of the three that EcoFlow documents as expandable, up to 5kWh.
• Highest continuous output: Anker SOLIX C1000 Gen 2. 2,000 W continuous and 3,000 W peak, with 1,024 Wh. It cannot be expanded. We show a link only for its single-unit amazon.ca listing; the amazon.com listing we have on file is a two-pack, so we have left it out.

If you need more than a day of fridge power without recharging, skip this class and look at larger stations or expansion batteries, using the 24 to 72 hour table above as your target.

Frequently asked questions

Can a 1,000Wh power station run a refrigerator overnight?

For many full-size fridges, yes. A 12-hour night needs average watts × 12 ÷ 0.85 of battery capacity. For the 62.3 W side-by-side example that is about 880 Wh, which a full 1,000Wh station covers. The 76.8 W bottom-freezer example needs about 1,084 Wh, which only the 1,152 Wh AC180 of the three stations covers. Start from a full charge and keep the doors closed.

How many watts does a full-size refrigerator use?

On average, the three ENERGY STAR models here work out to 45.9 W, 62.3 W and 76.8 W, from rated use of 402, 546 and 673 kWh per year. The running draw while the compressor is on is higher, and the start-up draw is higher again, which is why the station's output ratings matter separately from its capacity.

Why does the station's display show a higher number than the average?

The display shows what the fridge is drawing at that moment. While the compressor runs, that is well above the average; when it stops, it drops. The average is what sets runtime.

Is a bigger fridge always worse?

Not always. Rated energy use depends on the design as well as the size. In our examples, the 27.4 cubic foot side-by-side is rated lower than the 23.4 cubic foot bottom-freezer. Check the rated kWh per year for your exact model.

How we research: we compare manufacturer specifications, check published sources and run the numbers. We do not claim hands-on testing. Our methodology.