Calculate What Your Home Costs to Run

To calculate electricity cost, convert watts to kilowatts and multiply by time and your electricity rate. Keep in mind that appliances with thermostats, like refrigerators, do not draw their maximum wattage continuously.

Your electricity rate is typically found on your monthly utility bill, listed as the charge per kilowatt-hour (kWh). You can also divide your total bill amount by the total kWh used to find your effective rate. Note that many utilities use tiered or time-of-use rates, where the cost changes depending on when you consume energy.

Running a 1,500-watt space heater costs approximately $0.23 per hour, assuming a national average electricity rate of $0.15 per kWh. A key limitation is that space heaters cycle on and off once they reach the target temperature, so continuous running costs are usually lower.

Appliance estimates often assume average usage patterns, which rarely match real-world household habits perfectly. Additionally, your electricity bill includes fixed monthly service fees, taxes, and delivery charges that are not part of a device's raw energy consumption cost. Also, older appliances often operate less efficiently than their original rated labels suggest.

A typical central air conditioner uses between 3,000 and 5,000 watts per hour, while a window unit uses 500 to 1,500 watts. However, AC efficiency depends heavily on outdoor temperature, home insulation, and the unit's SEER rating.

Charging an electric vehicle (EV) at home costs about $9 to $12 for a full charge, depending on your battery size and local electricity rates. Keep in mind that charging efficiency is not 100%, and some energy is lost as heat during the process.