How to Calculate Appliance Electricity Costs
Electric utilities bill customers based on kilowatt-hours (kWh), while consumer appliances display power consumption in Watts (W). You can convert any device's wattage into real-world dollar amounts using this standard formula:
Cost = (Watts × Daily Hours ÷ 1000) × Electricity Rate ($/kWh)
Average Running Costs for Common Appliances
Understanding Kilowatt-Hours & Duty Cycles
One kilowatt-hour (kWh) equals 1,000 Watts running continuously for one full hour. However, appliances with cooling elements, heating coils, or compressors (such as refrigerators, space heaters, and window AC units) turn on and off based on internal thermostats. Their effective power draw is often 30% to 50% lower than the maximum nameplate wattage stamped on the manufacturer tag.