What Uses More Electricity: AC Or A Fan? See What I Found Out!

Yes, air conditioners are wonderful for cooling a room. I recently purchased one myself to get relief from the hot Georgia summer here. It was unbearable at times!

However, I was curious just like you about what uses more electricity – AC or a fan? I wanted to know not just which one uses more but by how much.

So I decided to do real-world measurements and show you which of the two draws the most power. I was pretty darn surprised by what I found!

Why I made my own measurements

Frustrated man at computer image
Have you tried figuring out power specifications for air conditioners or fans? If so, you have my sympathy! It’s often a pointless, time-wasting, and confusing process. Even worse, if you find listed specs they’re often not correct. I decided to find out for myself what I was dealing with.

Unfortunately, when searching for power consumption data from manufacturers you’ll find it’s either totally unavailable or somewhat incorrect (based on theoretical estimates). I don’t want to rely on estimates.

It’s rather frustrating to find out that very few if any air cooling product manufacturers offer decent specifications. Most have little to none available in my research.

In fact of the ones that do provider power ratings, often it’s only for the maximum (high-speed) settings. Lower speed settings such as low and medium had no specifications available at all!

Better just to find out for sure

In order to figure it all out and give you the best and most helpful information, I decided to take a hands-on approach.

I measured and compared the power consumption of an air conditioner and a fan that I own. They’re good, typical examples of what many people would buy and are a great reference point.

Products tested

AC vs fan electricity tested models image

For test purposes, I made power measurements using 2 typical products as examples. Left: A 5,000 BTU (small room) budget AC unit, the Emerson Quiet Kool window air conditioner. Right: A typical box fan used for cooling and white noise. Both are good choices as they’re popular and fit the price range many people shop in. They’re also around the same electrical power usage as many similar products on the market.

In order to get real-world data I knew it was important to measure power and collect data from real products in use.

What better way than with 2 of my air cooling products that very much like the ones you might use? To get good data, I measured electricity used from both my air conditioner and fan for a variety of power and speed settings.

To make it simple for you to see what it all means, I’ve provided a clear comparison graph and a measurement table as well below.

Measuring power use

Kill-A-Watt P4400 energy meter example

Rather than guess or rely on questionable manufacturer’s specifications, I used this inexpensive little energy meter from Amazon to check power consumption. Using the meter I was able to record accurate and reliable data to compare AC and fan power use.

I compared electricity used by recording measurements from this amazing little Kill-A-Watt P4400 energy meter I picked up from Amazon. It’s accurate to 2% and is fantastic for monitoring a variety of power supply details including wattage being consumed during use.

Measurement examples

In the image I’ve provided below you can see for yourself the measurements I took when testing. There’s an amazing amount of difference between the two!

I’ll cover this more in detail later.

AC vs box fan power measurement example pics

From top to bottom: Low, medium, and high settings I measured for power readings. You can see here the power use I observed for the air conditioner (left) and the box fan (right), measured in Watts. Notice how much more electricity the AC unit requires to run when cooling even when on low speed!

The results: AC vs fan electricity comparison data

I already had suspected that an air conditioner would draw more electricity to work that a standard ceiling or box fan, but I wasn’t ready for what I discovered!

As you can see below, not only does an AC unit use more electricity, but it requires a huge amount of power compared to a fan. Even when the cooling mode (compressor) isn’t in operation it’s at least almost the same power requirement as a fan at low speed.

How to read the measurements

Don’t worry, it’s actually quite simple! I just want to be sure there’s no confusion about what the numbers mean.

For the air conditioner, two main modes are available:

  • Fan only (no cooling): low, medium, and high
  • Cooling modes (compressor is in use): low, medium, and high

For the box fan, 3 speeds are available:

  • Low, medium, and high

I measured and recorded data for these settings for comparison in the table you see below. “Fan only” means the air conditioner is only powering the fan and isn’t actually cooling the air. While that’s a feature on many air conditioners, it’s not typically used often.

However, I measured the power consumption for those modes as well for reference purposes. I was dying to know more about how much power the air conditioner would draw when not cooling.

The most important values are at the bottom: these are a comparison of the low, medium, and high cooling settings used on both a fan and AC unit.

Those are what you should look at when comparing the two. (Note: “N/A” means not applicable, as a standard fan only has speeds to choose from as opposed to “cool” and “fan only” modes like an air conditioner).

AC vs fan electrical power comparison table

Measured / Setting Fan (Watts) AC (Watts)
Fan only (Low) N/A 57
Fan only (Med.) N/A 60
Fan only (High)  N/A 63.2
Low Speed 55 449
Medium Speed 66 460
High Speed 87 467

AC vs fan electrical power comparison chart

electric fan vs AC power use comparison graph

As you can see in the graph, for similar settings an air conditioner uses a TREMENDOUS amount of electricity vs a fan. So much so that even when the AC unit’s fan is set to low there’s very little benefit – the power draw is within a few watts or so still. You can see how much more efficient a fan is than an air conditioner using my data here. I was blown away by what I measured!

What I discovered from my testing is that not only do air conditioners (yes, it’s very obvious!) use more electricity than fans, but they can use up to almost 9 to 10 times as much as a fan does!

That can mean a very significant impact on your electric bill.

What really surprised me was how much an air conditioner uses when it’s on the low setting. It was only a few watts below medium or high!

Fan only modes

Although air conditioners do have a “fan only” mode, usually it’s simply not helpful to cool you and your room like a traditional fan can.

That’s because (1) the built-in fan has a lower airflow rate than those you buy and (2) they can’t be adjusted to blow air directly where it’s needed for effective cooling.

In the real world, an air conditioner needs to be left in the cool mode in which the compressor is in use. Because a compressor is essentially a motor-driven pump, it requires a substantial amount of power to work and produce cold air.

That’s why air conditioners need so much electricity: they use a compressor to move pressurized refrigerant. This requires a large amount of mechanical force and a substantial amount of electrical energy.

In fact, you can see this happen with a car: using the air conditioner requires the engine to do more work and will increase fuel consumption over time.

How air conditioners work

Window air conditioner exploded view diagram

Indoor air conditioners work by circulating refrigerant which, when forced through an expansion valve, creates a temperature drop that is used to blow cold air into the room. The room’s warm air is pulled out through the front panel and released into the outside. Fans are used to blow cold air into the room as well as blow the warm air from the condenser into the outside atmosphere.

Air conditioners work using some amazing – yet extremely important – principles of physics. When a high-pressure liquid (in this case refrigerant circulated under pressure from the AC unit’s compressor) is forced through an expansion valve a large temperature drop occurs.

This temperature drop results in a cold refrigerant side which is piped through a section called a condenser. A high-speed fan, commonly called a blower, then blows cold air into the room.

The existing warm air in a room is also drawn out and blown into the outside air.

Unfortunately, it takes a lot of electrical energy to drive the motor which turns the compressor which circulates refrigerant. That’s a big disadvantage that comes with using an air conditioner.

How fans cool you and your room

Fan cooling forced convection diagram image

Did you know? Fans don’t actually cool the air. They work by blowing across surfaces and removing heat into the nearby air, causing a temperature drop and a cooling sensation. Because they don’t need any heavy electromechanical devices as air conditioners use, they’re much more efficient in terms of electricity use. Note that certain fans are better than others depending upon your needs.

You might not be aware of it, but fans don’t actually cool you by blowing cool air. In fact, fans aren’t designed to drop the temperature of the air around you at all.

Instead, they rely on the concept of forced convection. 

What is convection cooling? How do fans cool you?

Does that sound like a strange or somewhat complicated concept? Don’t worry – it’s not. It simply means that forced convection cooling relies on moving air across your body and other surfaces in a room to move heat away into the surrounding air.

By doing so, the temperature is effectively reduced and you feel cooler.

Additionally, fans (depending upon the type, design, and features) can keep the air in a room continuously circulating which will prevent heat from building up.

Because of how they work, fans have to be pointed at the surfaces you want to cool in order to work well. They also will need to run continuously.

Once they’re shut off, the cooling effect stops since there’s nothing to transfer heat away from you.

Fans that have an oscillation mode are especially effective because they can continuously move automatically and blow air within a wide area in a room. Tower fans are especially helpful in this way and are very energy-efficient, too.

Recommended fans for cooling

Lasko T42950 Wind Curve tower fan example

Tower fans are a unique kind of cooling fan. Because of their tall design, they’re good cooling fans and offer a nice “wall” of soothing air in a room. Most use an oscillating feature to cover a very large area with circulating air for optimal cooling. Many also provide more advanced features that simpler models don’t.

For home cooling purposes, I recommend a tower fan. They’re especially well-suited for cooling you and your room because of their design.

Unlike traditional fans, they have a rotary fan blade design that has a very tall shape. When running they produce a very tall vertical area of air that’s great for cooling.

Additionally, most feature a side-to-side oscillation movement mode which allows them to blow a wide area of air within a room. Unlike standard circular or pedestal fans, they’re often better suited for keeping you comfortable.

You can find some of the best tower fans for cooling a room here.

Summary: AC vs fans – which uses more electricity?

I hope you’ve found my post helpful and informative! Here are the main points to remember:

  • An air conditioner uses roughly about 5-9 times as much electricity as a fan. While the amount may vary from model to model, this rule holds true for all of them.
  • Even on the low setting, an air conditioner uses as a very large amount of electricity when cooling
  • Fans are much more cost-effective in terms of energy use
  • Using an energy meter is a great way to make sure you know how much electricity your air cooling product is using

Do you have questions, comments, or suggestions about fans, air conditioners, or anything related? I’d love to hear from you.

Just post a comment below or reach out to me via my Contact page.

Your comments are welcome!

  1. Hello you did a really good job at presenting this. One of the things that I would have considered would be that I would be using 5 fans in place of one air conditioner. So with that said, 5 fans on high use 87 watts each, so the total watts for 5 fans is 437 watts. And the watts used for an air conditioner is 467. So in real time there is not much different from fans to air conditioner. Also fans are on all the time and air conditioner is not on all the time. So I believe it would equal out.

    Reply
    • Hi Mitch. Well, yes, perhaps it might equal out but it’s kind of an unusual comparison I would say, given that few people will ever use 5 fans. Also, there is one advantage that air conditioners offer some people: lower temperatures.

      The value I used for the air conditioner’s power use is actually even higher for larger units, so there would be a difference with those vs fans too.

      I would say that the biggest advantage would be using 1 or more fans vs central air conditioning units. Since they attempt to cool nearly the entire home or building they use quite a bit more energy than a window unit cooling a single room for example.

      Thanks for commenting. :)

      Reply
      • I don’t think it’s so much that one person will use 5, but five in total in a household vs AC. For example right now I have two fans running and the room next to mine has two running as well. If the last one had a fan it would easily reach 5. So I guess the thinking behind Mitch’s message is at one point in a house will everybody’s fans running all at once exceed the power of the AC.

        Reply
        • Hi Lucy. Actually you’d need close to 10 fans or more running on medium speed to exceed the power used by an air conditioner. That isn’t likely to happen in a typical home. There’s so much of a difference between how much energy the two use it would take somewhere around that many.

          Best regards.

          Reply
    • Thanks for this. You helped me decide whether or not to purchase an aircon. I live in the Philippines and it is super hot here. I use 5 fans but it isn’t really helping. I thought i would spend more paying electricity if i get an aircon. At least now i know.

      Reply
  2. Thank you.I live in the Caribbean and the heat and humidity can be downright nightmarish, but my electricity bill darn near gives me a heart attack. So I am trying to figure out how to utilize my fan more but survive in this heat.

    Reply
    • Hi Del. I’m sure it rough where you live! You might also check into evaporative coolers too, as they’re a fan combined with either water mist and/or ice to cool the room as well. There are big and small versions of them, including tabletop sized.

      Good luck! :)

      Reply
      • This is a bad idea the mist just increases the humidity making it feel hotter when used indoors. I work in a manufacturing plant that had these setup. Used it once with the mist and have never used again. Outdoors they are great because of the large space to dissipate the humidity created; indoors they make things worse.

        Reply
  3. Thank you willams
    For doing this experiment and share your result with for us .I was expecting that fans will take less power than airconditoner.i am glad I my expectaons were right .
    Keep up the good work.

    Reply
  4. Thank you so much for this! I was struggling to find numbers specifically for the fan only setting on my AC unit as I wanted to look at how effective using the fan mode would be in offsetting energy usage. Much appreciated!

    Reply
  5. I might be wrong, but I guess there’s a small silly mistake out there. The “low”, “medium” and “high” settings for the A/C could mean just the blower speed, while the compressor load remains roughly the same. Try changing the thermostat and see again.

    Reply
    • Hi, that’s “sort of” true. It’s impossible for me to account for each and every single operating mode of every model and brand AC unit. For example, “economy” mode would be different than max. or standard mode, etc.

      My main goal was to show (in basic terms) how much of a contrast there is between the power a fan and an air conditioner uses in typical use.

      The compressor definitely is the main culprit (as my article mentions), but the operation depends on the particular AC unit. Setting the thermostat lower would have the same result just that it would run longer, thereby using more electricity over time [kilowatt-hours] vs. a higher temp setting. That’s because it would need to run much longer on warm days to maintain the lower temperature.

      Thanks for dropping by. :)

      Reply
  6. Thank you. Your information has answerd my question. Ive always wondered about the power usage. You have solved my problem.

    Reply
  7. Just read your post but like someone else mentioned where I live with high humidity levels in my small living room I have 5 fans going just to get a very little relief I have found I try to keep fans going as long as I can to make my electric usage high for only 5 months out of the year but with the spring and summers getting hotter each year it’s getting difficult to do that. So in my small 1100 square foot home 3 air conditioners cool better and by your findings I think would use equal electric but AC would definitely make me be able to sleep thank you I would have never had the patience to do all that.

    Reply
    • Good morning, Barbara. Yes, fans can’t lower the humidity they basically help cool you off by blowing air instead of lowering the temperature (and also reduces humidity). So sometimes using the AC is much more comfortable. Thanks for dropping by. :)

      Reply
  8. I live in a 2 story townhome and the master bedroom upstairs is always hot in the summer. I do have central air but doesn’t cut-it to get the bedroom cool enough to sleep comfortably. I have 3 fans running..one at the base of the stairs going upwards to the 2nd floor, another one in the upstairs hallway going into the bedroom and then the third table-top oscillating fan in the actual bedroom. The one fan at the base of the stairs runs when I am home so the upstairs does not get so stifling hot that it takes 5 hours to cool down. The other two fans only go on when I’m ready to go to bed. This has worked okay but I am wondering if I get a very small energy efficient 5,000 BTU window air conditioner (I found one that says on average the cost is around $44 a year) for that bedroom and run it at night only would be sufficient? Or should I continue using the fans like I have always done. I appreciate your feedback and I’ll be waiting to hear from you.

    Reply
    • Hi Amy. An air conditioner like that would be a good idea. In fact I used to do the same for a bedroom. If the bedroom is relatively small in size it should be ok for cooling it down (if the door is shut).

      Fans are helpful but honestly sometimes you need AC like during those hot summer nights.

      Reply
      • Thanks, Grant, for your research. I live in a small one bedroom apt., and I’ve just bought an oscillating floor fan. I am trying not to use the ac at all because it’s so expensive. Will it be cost effective to leave the fan on most of the day and only a few hours during the night? I’m a senior on a fixed income.

        Reply
        • Hello Linda. If you’re at home during the day, yes it’s fine but leaving it on at night only a few hours isn’t necessary. You can leave it on most of the night if you like since they cost little to run.

          Reply
  9. In the afternoon on the West side windows ,I turn the portable floor fans away from the room, pointing blades toward the open window, it is forcing the hot air out. On The North side windows I point portable floor fan blades to inside the rooms blowing cooler air, this creates a cross breeze, making the apartment livable. I don’t get humid hot air in North eastern Ontario very often.

    Reply

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