BACKUP POWER
How Many Watts Are Needed to Run a Refrigerator?
Estimate refrigerator running watts, starting surge and battery or generator capacity for an outage.
Many household refrigerators draw roughly 100–250 watts while the compressor runs, but starting surge can be several times higher. Use the appliance label or a meter that captures surge; do not size backup power from an average-watt estimate alone.
- ✓ Running watts are not starting watts
- ✓ The compressor cycles
- ✓ Size the inverter for surge and the battery for energy
Power and energy are different
Watts determine whether an inverter can start and run the refrigerator. Watt-hours determine how long a battery can support it. A refrigerator that averages 70 watts over a day uses about 1.68 kWh per 24 hours, even if it draws 180 watts while the compressor is on.
Get a useful measurement
Check the manufacturer label and manual, then use a suitable energy monitor over at least 24 hours. For backup equipment, confirm that the inverter’s continuous and surge ratings cover the refrigerator plus every simultaneous load.
- Include defrost-cycle power
- Allow headroom for compressor surge
- Keep refrigerator doors closed during outages
- Do not use indoor combustion generators
Turn the measurement into a backup size
Multiply measured daily kWh by the fraction of a day you want to cover, then divide by the usable battery fraction and conversion efficiency. Add other essential loads separately and verify compatibility with the equipment supplier.
Actual energy use and product performance vary by equipment, conditions and installation. Confirm measurements and manufacturer specifications. Qualified professionals should handle permanent wiring and transfer equipment.