How Much Energy Does an Air Conditioner Use?

It happens every year: Summer weather starts, the AC kicks on and your electric bill shoots up. Your air conditioner can add quite a bit to your home’s energy use. 

How much energy your AC uses depends a lot on the climate in your area, but factors like the type and age of your air conditioner, the energy efficiency of your home and your preferred temperature can all affect your electric bill during the hot summer months. 

There are a few different ways to tell — or at least estimate — how much energy an air conditioner uses. You can also make changes ranging from small adjustments to large-scale projects to reduce your air conditioner use, keep your home comfortable and cut those high energy bills. 

How much electricity does a typical air conditioner use?

Air conditioning is a significant portion of annual energy use in American homes. According to the US Energy Information Administration data, air conditioning accounted for 19% of the energy use in US homes in 2020 — a whopping 254 billion kilowatt-hours. The EIA also found that in 2022, almost 90% of American households used air conditioning, and two-thirds of households used a central air conditioning unit like a compressor or heat pump. 

A typical central air conditioning unit uses somewhere between 3,000 and 3,500 watts, while window units range from around 1,000 to 1,500 watts. It’s important to note that because an air conditioner’s performance can be affected by so many variables that your AC’s energy use and cost to run could vary significantly. 

“It depends on the size of the house, the wattage and the BTUs,” said Eric Goranson, a Seattle-based designer and home renovation expert who hosts Around the House, a podcast and nationally syndicated radio show. “But the average monthly cost for most people is anywhere from $70 to $144 a month in the summer.”

The type of cooling system in your home can also affect energy use, but not as much as you might think. Central HVAC systems with heat pumps use a comparable amount of energy as a conventional air conditioner, Goranson said. The energy and cost savings of a heat pump are generally more significant with winter heating. 

According to the US Environmental Protection Agency, a central air conditioning unit in a typical American home consumes 2,500 kilowatt-hours of energy each year. With an average cost of $0.175 per kilowatt-hour of electricity in May 2024, according to the US Bureau of Labor Statistics, running the air conditioner adds an average of $437.50 to Americans’ utility bills each year.   

How to determine how much energy my air conditioner uses

If you want to pinpoint how much energy your air conditioner uses, there are a few ways you can go about it. One is to gather some basic information about your home and appliances and calculate a ballpark number yourself. 

Your electric utility may also provide some information about your energy usage, either on your monthly bill or on their website. In addition to the change in usage over time, you may be able to see a breakdown of different types of appliances or systems in your home and how much energy they’re using for each pay period. 

However, Goranson notes, your utility’s usage breakdown may not be based only on specific data from your household but from home monitoring systems of other customers in your area and past usage in your home. To get personalized, instant usage data, he suggests installing a home energy monitor. Devices made by brands like Sense, Wiser Energy and Curb can give you real-time information about which electrical appliances and devices add the most to your bill.

“I have a product called Sense that hooks into the electrical panel and monitors that system,” he said. “It uses AI technology to know, say, an AC unit from a curling iron. Then you can look at the app and know exactly what’s going on with your energy use.” 

What affects an air conditioner’s energy use?

When it comes to individual air conditioning units, energy use ranges widely. The size, age and type of unit, the temperature outside and your desired temperature in the home, among other factors, will all affect how much energy your air conditioner uses to cool your space. 

Keeping your AC unit in good shape also makes a big difference. Cleaning or replacing filters, cleaning coils, straightening fins and unclogging channels can improve an air conditioner’s airflow, energy efficiency and overall performance. It’s a good idea to get your HVAC system serviced annually to perform necessary maintenance and prevent small issues from turning into bigger performance problems down the road. 

The set temperature on your thermostat will also determine how hard the unit has to work to cool your space. Because an air conditioner can only cool your home down to 15 to 20 degrees Fahrenheit below the temperature outside, blasting the AC at a much lower temperature in hopes of cooling the space faster can actually waste energy and cost you more. 

How to reduce your air conditioning costs

One of the best ways to cut down on air conditioning use is to cool your home naturally when possible. If you’re in a region where summer means cool mornings and hot days, you can open windows in the morning to lower the temperature inside. When the temperature starts to creep up, close your windows, shut the blinds and turn on your AC — which won’t have to work as hard to keep your home comfortable.

Another is to protect your house during the hottest parts of the day with shade — whether by planting trees, installing awnings or closing the drapes or blinds. Even basic window coverings can help insulate your home from the sun’s heat, but energy-efficient window treatments like window films and cellular shades can have more of an impact. Look for items rated by the Attachment Energy Rating Council, or AERC. 

Another way is to bump up the set point of your thermostat to achieve optimal efficiency. The US Department of Energy recommends setting your thermostat between 74 and 78 degrees Fahrenheit during the day in summer to keep your space cool and reduce humidity while allowing your air conditioner to operate most efficiently. The recommended temperature at night is 82 and 85 F when you’re away from the house. 

Keeping your air conditioner clean and maintained will save you money in the long run. 

“You really need to stay on maintenance,” said Goranson. “Having somebody come out once a year and service your unit and clean it out makes a big difference. Your outside compressor unit out there can get full of dirt and dust in the coils, which makes it lose that efficiency. Then cooling your home is more expensive, because it has to work harder.”

But if your system is getting on in years — most air conditioners have a lifespan of 15 to 20 years — it may be time to consider an upgrade. Whether you’re thinking about installing a new air conditioner or getting a heat pump, a new, more efficient system could be worth the investment. Inflation Reduction Act tax incentives could also help offset the cost.

“If you’ve got a 20-year-old system, it’s probably a single-stage system. When it kicks on, it’s a hundred percent, kind of how window air conditioners work,” Goranson said. “Newer, more efficient models have variable speed compressors, meaning they can run at lower speeds to adjust the temperature and not use all that energy.”