Outage planning guide
How long will a portable power station run a refrigerator?
Refrigerators cycle, so average watts are more useful for runtime than compressor nameplate watts. You still need enough surge output to start the compressor.
Backup power runtime
Estimate steady-load runtime after inverter losses and a safety reserve.
Runtime = capacity × efficiency × usable battery share ÷ average load. Motor surge, temperature, battery age and device cycling can change real-world runtime.
What changes the answer?
Measure average load over a complete cycle
A refrigerator may draw several hundred watts while the compressor runs and much less between cycles. A 24-hour energy reading gives a stronger average than a single instant.
Continuous watts and startup surge solve different problems
Battery capacity determines approximate runtime. Inverter output determines whether the power station can start and sustain the compressor at all.
Door openings and room temperature change the result
A hot kitchen, warm food and frequent door openings increase compressor duty cycle. Plan conservatively during summer outages.
Use this result as a planning range
This estimates electrical runtime, not how long food remains safe. Follow official food-safety guidance during an outage.
Review the formulas and public sources in our methodology.
Official references
- Analyzing household electricity loadsU.S. Department of Energy
- Food safety during a power outageFoodSafety.gov
- Generator and carbon-monoxide safetyU.S. Consumer Product Safety Commission