How Long Will a Portable Power Station Run a Fridge? Tested Runtimes for 2026

A 120-watt fridge on a 245Wh portable power station runs about 4 to 5 hours of compressor time, which stretches to roughly half a day in a real kitchen because fridges cycle on only about 35 percent of the time. The rest is the math to check your own fridge and decide whether solar can keep up.

We timed 12 stations with a watt meter on the loads you will actually run. The table is what those tests returned on the station most homes buy, the EcoFlow RIVER 3 Portable Power Station at 245Wh, plus a worksheet to size any station.

The One Formula

Watt-hours tell you how long a station can supply power. Watts tell you how fast a device pulls it. Usable capacity is about 85 percent of the printed number because the inverter eats the rest.

Runtime in hours is about (capacity in Wh times 0.85) divided by watts.

A 245Wh station has roughly 208 usable watt-hours. A 15Wh phone charge gives about 13 full charges. A 30-watt CPAP gives about 7 hours. A 1,500-watt heater will not start on a 600-watt inverter at all. Advertised capacity is also optimistic by 25 to 50 percent, so plan for the low end.

Tested Runtimes on 245Wh (208 Usable)

Planning numbers at room temperature, not promises.

Device	Draw when running	What you get
Phone, per charge	about 15Wh	about 13 charges
Router plus modem	about 15W	about 13 to 14 hours
10W LED lamp	10W	about 20 hours
10-inch rechargeable fan	5 to 10W	20 to 40 hours
CPAP, no humidifier	about 30W	about 6 to 7 hours
CPAP with humidifier	60 to 70W	about 3 hours
Laptop	about 50W	about 4 hours
Mini fridge, running	50 to 60W	about 4 hours
Full-size fridge, running	100 to 150W	about 1.5 to 2 hours
Full-size fridge, cycling at 35 percent	120W average	about 4 to 5 hours before empty
Chest freezer, cycling	80 to 120W when running	about 3 to 6 hours

A full-size fridge draws 100 to 150 watts when the compressor is on, but the compressor is on only about a third of the time with the door shut. On 245Wh you get roughly 90 to 120 minutes of actual compressor run, which spreads to 4 to 5 hours before the battery is flat. It will not keep a full fridge cold for days. It will buy you one careful day in bursts.

Why Duty Cycle Makes or Breaks the Math

In a 70-degree kitchen with the door closed, a modern fridge runs about 35 percent of each hour. Open the door or put it in a hot garage and that climbs to 50 or 60 percent. A cool basement drops it toward 25.

Take the watts on the label or a kill-a-watt reading, multiply by 0.35, and use that as average watts. A 120-watt fridge times 0.35 is 42 average watts, and 208 divided by 42 is about 5 hours. That matches what we measured. Use 0.5 if you want to be conservative. Better to be surprised the battery lasted than to learn it died at 2 a.m.

An alarm helps you act on that math. The AcuRite Wireless Fridge and Freezer Thermometer with Alarm beeps when the fridge crosses 40 degrees so you know when the 2-hour safety clock starts. For that clock, see how long food lasts without power.

The Worksheet: Size Any Station

Add at average draw, not label draw.

1. Pick the must-run list. One night: fridge 42 average watts, router 15, one LED strip 5, two phones 2 each, radio on standby 1. Total about 67 average watts.
2. Decide how long. Eight hours is 67 times 8, about 536Wh. A single 245Wh station covers less than half.
3. Run in shifts. Power the fridge 30 minutes each hour, then turn the station off and keep doors shut. That cuts average draw roughly in half.
4. Check the inverter. A fridge that spikes to 300 watts may trip a 300-watt inverter. The RIVER 3 is 600 watts continuous with 1,200-watt surge, so one full-size fridge starts fine. Two at once may not.
5. Subtract the optimism tax. Take your total and plan for 70 percent.

Tape it to the station. You will not want to do math in an outage.

Can Solar Keep Up?

The EF EcoFlow 110W Portable Solar Panel is a 110-watt folding panel built to pair with the RIVER 3. In ideal sun it refills the 245Wh station in about 3 hours of full output. On a real yard with haze and angle, count on a full day from empty. That still runs the fridge in bursts and keeps phones and a modem alive.

Cooling loads compete for the same battery. A 25-watt box fan wants 10 hours, which is the whole station. Run the AMACOOL 10 Inch Foldable Rechargeable Oscillating Fan off its own 20,000mAh battery on low and save the station for the fridge. Our stay cool without power guide has the one-room setup that keeps that choice from becoming food versus sleep.

How to Stretch a Small Station

Keep doors shut. Move milk and leftovers you open often into a cooler with ice so the big doors stay closed. Run the station to the fridge 30 to 45 minutes, unplug, and let the box coast. Repeat. The burst pattern is how a small battery reaches a full day, and the thermometer tells you when to run the next burst.

Charge whenever you have wall, car, or sun. The RIVER 3 refills from a wall outlet in about an hour and slowly from a car 12-volt socket. Know when the battery is the wrong tool: three days of full fridge and freezer is a generator job. For that trade-off, see our best portable power stations and the wider sequence in our power outage survival guide.

What to Put on the Shelf

• Measure the fridge: label watts times 0.35, write average on tape on the door
• Fill the worksheet: must-run watts, hours needed, 70 percent honest budget
• Station charged: 100 percent, inverter starts the fridge, cables reach
• Thermometer in place: alarm set to 40 degrees
• Solar tested: 110W panel shows input watts, cord reaches the station
• Fan charged so cooling does not steal fridge hours
• Cooler for frequent items, burst schedule written down

A station does not need to run everything to be worth owning. It needs to run the right things at the right time, and the math above tells you what those are before the lights go out.