Run a fridge for 24 hours from a power station

Target

24 hours

Planning load

165 W

• Running watts: 500 W
• Duty cycle (%): 33%

Estimated nominal battery

5,200 Wh+

Scenario confidence

estimated

Verify your watts

• Check the device label for running watts or input amps and volts.
• Use a plug-in watt meter for AC loads when the result matters.
• For cycling loads, measure long enough to capture on/off behavior.

Open wattage library

Check output path

• AC inverter loads usually lose more energy than direct DC loads.
• Keep reserve for cold weather, battery age, and load changes.
• Do not treat label capacity as fully usable watt-hours.

Read the method

Check surge and output

• Runtime does not prove a station can start a compressor or motor.
• Compare device startup watts with the station surge rating.
• Compare running watts with the station continuous output rating.

Check startup surge

Load energy

165 W × 24 hours = 3,960 Wh

Usable factor

85% × 90% × 100% × 100% = 0.77

Estimated nominal battery

3,960 Wh ÷ 0.77 ≈ 5,200 Wh

Scenario behavior

A refrigerator is treated as a cycling compressor load. The running-watt default is averaged by duty cycle, so ambient temperature, door openings, and thermostat settings can move the result.

Wh-class guidance

Use the computed Wh as a planning floor. Choose a larger class when the room is hot, the fridge is older, the battery is aged, or startup surge/output headroom is unknown.

Assumptions used

• Full-size refrigerator: 300-800 W
• Efficiency (%): 85%
• Reserve kept unused (%): 10%
• Output path: AC inverter
• Battery health (%): 100%
• Cold weather loss (%): 0%

Caveats

• Measure the fridge if food safety depends on the plan.
• Runtime math does not prove the station can start the compressor; check startup surge separately.
• Solar input can help during daylight, but this page sizes the battery without assuming solar recovery.