How to Calculate the Cost of Cooling

Cooling cost depend on the wattage of the cooling appliance.

The amount you spend on cooling is determined by the wattage of the appliances you use to cool your room or home. Central air conditioning is the most expensive, followed by room air conditioners. Using fans can save a lot of money, and fans in combination with air conditioners work well, allowing you to reduce air conditioner usage for the same amount of cooling. Your electricity cost per kilowatt hour is set by your utility.

Things You'll Need

• Calculator
• Recent electric bill

Instructions

1. Determine the wattage for the cooling appliances you are calculating. The wattage should be listed on the appliance or in the user's manual.

2. Estimate the number of hours each appliance runs during the month.

3. Multiply the number of hours each appliance is run monthly by the wattage to get a total figure of watt hours for the month for each appliance. For example, operating a room air conditioner that runs at 800 watts for 200 hours a month represents 160,000 watt hours.

4. Add together all the watt hours for the cooling appliances you are calculating and divide the total by 1,000 to get the number of kilowatt hours, the unit utilities use to charge for electricity. If, for example, your air conditioner uses 160,000 watts per month and a fan uses 40,000 watts per month, that is 200,000 watt hours or 200 kilowatt hours.

5. Refer to your electric bill to see what your utility charges per kilowatt hour and multiply it by your total kilowatt hours for the month to get a monthly cooling cost calculation. In this example, 200 kilowatt hours times a 15 cent cost per kilowatt hour would be a $30 per month cooling cost.

References

• National Teacher Enhancement Project: Measuring Energy Usage
• Michael Blue Jay: Saving Money on Air Conditioning