Which Uses More Electricity, Air Conditioners or Refrigerators?

Calculating Electricity Usage

• Appliance manufacturers use volts, amps and watts to describe electricity usage, but your electricity company measures usage in kilowatt-hours. A kilowatt-hour is the amount of electricity an appliance uses in an hour, measured in units of 1,000 W. A 4,000-watt appliance uses 4 kW, or 12 kWh over the course of three hours; a 100-watt appliance uses 0.1 kW, or 0.3 kWh over the course of three hours.

Air Conditioners

• According to the Otter Tail Power Co., a small air conditioning system uses 3,500 W. If your home is larger than 1,200 square feet, your air conditioner is probably larger and uses more electricity. Otter Tail estimates that a typical customer uses his air conditioner for as many as 287 hours during a summer month, resulting in a monthly electricity usage of about 1,005 kWh.

Refrigerators

• Your refrigerator runs all day and night, so you'd expect it to use more electricity than your air conditioner. Yet it only uses only between 300 and 780 W, depending on the model. At 225 hours a month, which Otter Tail lists as median usage, your refrigerator uses 68 to 176 kWh per month. At most, this in one-sixth the amount of electricity your air conditioner uses.

Cost Difference

• As of June 2011, the U.S. Energy Information Administration lists the price of electricity at 11.6 cents per kilowatt-hour. So your air conditioner accounts for about $117 on your electric bill in the summer, and your refrigerator accounts for $8 to $21 in any given month.