Which AC Units Use the Most Electricity (and Which are the Most Energy Efficient)

As the weather gets warmer, we’re inclined to pack away the space heaters and throw open the windows. Depending on the day, you may want to flip on the ol’ AC unit. But with many consumers being more conscious of the energy they use (and how it affects their wallet); you may want to hold off on blasting that arctic air.

Do Air Conditioners or AC Units Use a Lot of Electricity?

It actually depends! Most of us are familiar with central air conditioners and stand-alone units, like window ACs. But there are other options as well, all of them consuming varying amounts of electricity.

How Much Electricity Does a Central Air Conditioner Use?

Central AC is a whole-home cooling system wherein the air is cooled in one location and circulated throughout to/from rooms with fans and through ductwork. Typically, a central AC system uses 3,000 to 5,000 watts per usage hour (running on the cool setting).

To give you some insight, if you run your AC on the fan setting, it drops to 750 watts per hour. According to the Appliance Analysts, the average cost of running a central AC is $76 to $168 per month, coming out to $900 to $1,200 per year.

Keep your AC running with an AC tune-up from our sister brand, One Hour Heating & Air Conditioning.

Do Window AC Units Use a lot of Electricity?

By comparison, AC Window Units use approximately 500 to 1,500 watts of electricity.

Keep in mind that it takes more than one AC window unit to cool a home. You’ll need one for each room of the house you want to reduce the temperature.

Here’s an ice cube for your glass! Wattage tells us how much electricity the AC uses at maximum power, but not how much it uses to maintain the temperature. To reduce an 88-degree room to 68 degrees requires a lot more work. Here’s an example from Appliance Analysts:

A 900W AC uses less electricity per hour than a 1000W AC, right? But a 1000W AC might cool your room in 20 minutes, while a 900W takes 30 minutes. And they may both use the same average of 400W to keep your room at that cool temperature.

Energy Saver Window Unit ACs allow for reduced electricity costs. These units alternate between the fan and the compressor function, meaning your home will stay cool without overloading your appliance.

For ways to make your home more energy-efficient, watch our video 6 Energy Saving Tips.

Portable AC Units typically use more wattage than window units or central units (even though they don’t require ducts). These units can use 3,000 to just over 4,000 watts per hour. There are different types of portable units, from compact rollers to fridge-like boxed towers, and they vary as far as energy consumption is concerned. These can run between $85 to $160 per month.

Are There Environmentally Friendly AC Options?

Hybrid/Dual Fuel ACs – Hybrid (dual fuel) ACs are a cost-effective alternative to traditional HVAC units in that they are both electric-powered and rely on a fuel source like propane or natural gas.

These units pull outside air in through the heater to create warmth throughout your home. In the warmer months, you can reverse the heat pump’s operation to permit cool air to flow through your home.

It may cost more to install a hybrid unit, but in the long run, you’ll be spending about 1/3 less than you would with another type of unit. Hybrid HVAC systems have less of a carbon footprint.

Mini-Split (ductless) AC Units don’t require full-sized ducts. Whereas central ACs distribute cool air through large ducts, mini-splits operate via an individual fan and evaporator unit in each room.

These units allow you more control over the temperature of your room, are quieter, more energy-efficient, and ultimately cheaper (as you aren’t paying for whole-room cooling coverage)

What’s the Right Choice for My House?

When choosing an air conditioner, take a look at the BTU (British Thermal Unit), a term also used in the U.S. The BTU rating is the measure of an AC’s cooling capacity over an hour, specifically the amount of heat that a unit can remove from a room.

It’s important to invest in an AC that has the right BTU to fit your needs. An AC that has a bigger BTU than what a room needs will short cycle, causing it to cool off the room too quickly and shut off, leading to uneven temperatures and a higher energy bill.

Read about more causes of short cycling.

Conversely, installing an AC that is too small for your space won’t be powerful enough to cool down your room. It will have to run continuously, which wastes energy.

Use this BTU calculator to figure out what size AC unit you require.

Just because the temperature is heating up doesn’t mean you have to go broke to stay cool. Knowing how much energy you’re using, the wattage, and BTU of your AC unit can go a long way in reducing your electricity bill.

Contact your local Mister Sparky for more energy-saving tips!