How to Calculate Your AC’s Monthly Energy Cost

March 21, 2018

According to the Energy Information Administration, heating and cooling accounts for almost 50% of an average American home’s energy consumption. This number has already decreased by 10% from 1993 in part because of more energy efficient technologies and innovations that happened in recent years, and additionally, because of growing awareness and responsibility on the part of consumers. Regardless, the amount of energy consumed for operating your HVAC remains staggering.

There are many ways to find out just how much you’re paying every month for your heating and cooling. No doubt you’ll find an HVAC operating cost calculator with a quick search on the web. But if you’re looking for a quick, straightforward guide, here’s everything you need to know.

Energy Ratings and Units

No HVAC operating cost calculator is complete without a brief discussion of an AC unit’s SEER rating. A SEER rating reflects your system’s energy efficiency and this information is readily available in product labels, manuals, and even the manufacturer’s websites. A lower rating means poor efficiency while a high number means the opposite. Energy-efficient air conditioning units will typically have a rating of 7 or higher.

Hourly Consumption Rates

Your air conditioning unit will also have a heat capacity alongside its SEER rating and you will need this to calculate your AC’s power needs. Heat capacity is measured in British Thermal Unit-hour or BTUh and it’s a measure of how much heat the system can process.

Once you’ve located both numbers, simply divide the capacity by the SEER rating to get how much wattage your AC uses per one hour. For example, an AC unit with 27,000 BTUh heat capacity and a SEER rating of 7 will use up 3,857 watts in an hour.

Monthly Cost

Once you have determined the hourly rate, it’s fairly straightforward to get a monthly cost. Let’s take the above example and give it a sample running time of 8 hours in a day. Multiply the hourly consumption rate by the number of hours it runs daily, and then multiply the result by 30 to represent a month. In this example, you should get about 925,000 watts/month, or 925 kilowatts/month.

To get the total monthly cost, multiply the monthly consumption rate with your local energy company’s pricing and you’ll get an accurate of idea of how much your AC costs to run.

Painless HVAC Services by Brody-Pennell

To learn more about energy consumption costs and how you can save on your monthly utility bill, contact the experts at Brody-Pennell at (310) 836-0606 today. Our staff is more than happy to answer all your questions about air conditioning and energy efficiency.


About The Author

Brody Pennell

Since 1945, Brody Pennell Heating & Air Conditioning is the committed to helping homeowners in the greater Los Angeles area experience total home comfort. In 2021, the readers of the Los Angeles Times voted Brody Pennell the Best HVAC Company in the area.

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