The average refrigerator consumes 600 to 800 kilowatt-hours of electricity per year, reports the Federal Trade Commission. If you've already removed the sticker, check your owner's manual or refer to the manufacturer's website to find this information.ind the monthly operating cost by multiplying your daily cost by 30. At the California average electricity price, a 300-watt unit costs $11.70 per month, or $140.40 per year. Refrigerators with a lower wattage rating will require much less energy, and thus cost much less to operate.