Electric fans might be the most-used appliance in your house. They’re portable, affordable, and easy to use. But just how much electricity do they use?
Knowing how much energy your fans use can help you use them wisely and save money every month on your electric bill.
Electric Fan Energy Use Explained
Fans work with the help of a motor. The motor spins the blades of the fan, which then forces air through the room. Depending on the size of the motor and how fast it’s spinning, the fan will draw a certain amount of electricity. This is measured in watts, written as “W”.
Electricity usage over time is measured in kilowatt-hours (kWh). One kilowatt-hour represents one thousand watts of power over the course of one hour. For example, if you run a 100-W fan for 10 hours, you use 1 kWh of electricity. The price of electricity is usually billed on a per kWh basis, depending on your utility company.
Average Wattage Usage of Electric Fans
Since there are many different types of fans out there, wattages can vary. Here are average wattages of each type of electric fan:
- Office desk fans: 5 W – 30 W
- Tower fans: 30 W – 100 W
- Pedestal fans: 50 W – 100 W
- Box fans: 40 W – 100 W
- Ceiling fans: 15 W – 90 W
Of course, different fans will fall into these ranges. As you can see, desk fans require the least amount of electricity out of any type. They are perfect for providing quick relief in a small space without drawing too much power. Box fans and pedestal fans move the largest volume of air but require more electricity to do so.
Pedestal fans range from light-duty desk fans all the way up to industrial-sized fans used in warehouses. Ceiling fans fall somewhere in the middle but are better at cooling a room than other types of fans.
Electric Fan Speed Settings and Energy Consumption
The speed at which you set your electric fan also affects power consumption. Most fans have at least three speed settings. Electricity usage can almost double when switching from the lowest setting to the highest.
As a general rule of thumb, fans only consume about 30 to 40 percent of their maximum wattage when on the lowest speed setting. The medium speed setting will draw about 60 to 70 percent. High speed will cause the fan to operate at between 90 and 100 percent of its rated wattage.
Variable speed controls can help you adjust your fan to the ideal speed. By dialing in the perfect setting, you can reduce average energy consumption by up to 25 to 35 percent.
AC Motor vs. DC Motor Fans
Now we’ve covered the basics of fan wattage and speed, let’s talk about motor types. Fans can contain either AC motors or DC motors.
AC stands for alternating current while DC stands for direct current. Almost all fans produced before 2010 used AC motors. Newer, energy-efficient fans use DC motors, also called BLDC (brushless DC) motors.
DC motors consume 30 to 50 percent less energy when compared to AC motors. For example, a traditional ceiling fan with an AC motor uses around 50 to 75 watts of power. The same size BLDC ceiling fan uses only 26 to 40 watts to produce the same amount of airflow.
Over the course of the summer, that adds up to big savings on your next electricity bill. How do DC motors use less electricity? DC motors use permanent magnets rather than copper windings. This means that less electricity is wasted as heat.
DC motors can reach efficiency ratings of up to 85 to 90 percent. Traditional AC motors max out around 75 to 80 percent. By swapping to a DC motor fan, you can immediately reduce electricity consumption.
How Much Does It Cost To Run An Electric Fan?
Okay, now that we know how efficient fans can be. How much do they actually cost to run? The average cost of electricity in the United States is 17 cents per kWh.
If you run your pedestal fan for eight hours straight at 80 watts per hour, that equals .64 kWh for that day. Multiplying .64 kWh by 30 days in the month equals 19.2 kWh per month. At 17 cents per kWh, your monthly bill would be $3.27. Compare this to running a central air conditioner, which uses anywhere from 1,200 watts to 3,500 watts.
Running your ceiling fan 24 hours a day, every day costs just under $6 per month. This means fans are approximately 99 percent more efficient than your air conditioner.
Heating vs Cooling With Ceiling Fans
Did you know that ceiling fans can be used for both heating and cooling? Most ceiling fans have a switch that changes the direction the blades spin. When heated air rises to the ceiling, it slowly cools and falls back down to the ground.
During winter, you can use your ceiling fan to recirculate warm air around the room. Set your fan to low and reverse, allowing the fan to push air down towards the ground. You can effectively decrease your heating bill by forcing your heater to do less work.
You can save up to 40 percent on cooling and heating costs by using your ceiling fan properly. Remember, fans do not lower the temperature in a room. Instead, they make you feel cooler by evaporating sweat off of your skin.
Should You Use Fans?
Fans are a great way to keep yourself or your home cool during the summer. They use significantly less power than air conditioning units and cost only a few dollars a month to run.
Whether you choose to purchase an inexpensive box fan or a top-of-the-line BLDC ceiling fan, understanding fan power usage can help you keep your energy costs low.
Case Study Example: Household Electric Bill Decreases After Installing Efficient Ceiling Fans
One homeowner from Austin got frustrated that their summer electric bills were still high even though they already avoided running the air conditioner during the day. Their house was equipped with several AC motor ceiling fans which ran frequently all summer long.
The homeowner had a home energy audit and swapped out 4 old ceiling fans for energy-efficient ceiling fans that used BLDC motors to optimize airflow and minimize power draw.
They also implemented some behavioral changes:
- Turn fans off when not in the room
- Run fans on a lower speed setting at night
- Use ceiling fans with natural ventilation at night instead of the air conditioner
- Set thermostat temperature higher when using fans to circulate air
Outcome: 3 Months Later
“This summer my electricity bill was noticeably lower than last year. I feel like my house is airier since upgrading the fans, and they’re much quieter now with adjustable speed settings. Just changing when the fans are on and lowering the thermostat a few degrees while we use them has helped lower our energy usage during the summer.”
Study Conclusion:
DC motor ceiling fans consumed less electricity than their AC motor counterparts but provided comparable amounts of airflow.
CEILING FAN USE VS. AC: Ceiling fans don’t make a room cooler but using them efficiently can allow you to lower cooling costs.
Learn More: https://www.energystar.gov/products/ceiling_fans
Electric Fan FAQs
Do fans use a lot of electricity?
Fans are very energy efficient. The majority of fans use less than 100 watts of electricity.
Are ceiling fans less expensive than air conditioning?
Yes. Fans use much less energy than air conditioners. Ceiling fans might only use 50 watts or less, while your air conditioner can use upwards of 3,000 watts.
How much does it cost to run a fan continuously?
Ceiling fans can cost less than $0.50 per month to run 24/7. The exact cost will depend on your fan wattage and electricity rates.
What kind of fan uses the least electricity?
Fans that use direct current (DC) motors designed for energy efficiency will use the least amount of electricity.
Stick with desk fans and efficient ceiling fans. Avoid large pedestal fans or outdated AC motor ceiling fans.
What is the difference between AC ceiling fans and DC ceiling fans?
AC stands for alternating current while DC refers to direct current. DC ceiling fans operate on technology that allows them to use 30–50% less electricity and run quieter than AC ceiling fans.
Does changing fan speeds use more electricity?
The higher the fan speed, the more electricity your fan will use. Using your lowest or medium speed will help keep energy consumption low.
Will fans decrease my electric bill from air conditioning?
Yes! Fans can make a room feel cooler so you can adjust your thermostat upwards by a few degrees to save money on cooling.
Can I leave my ceiling fan on all night?
Ceiling fans use a negligible amount of electricity, so it’s fine to leave them on overnight if you’d like. However, you should still turn off ceiling fans in rooms you’re not using.
Are tower fans better than standing fans?
Tower fans can be more efficient, but pedestal fans can also be energy efficient. High wattage pedestal fans that move a lot of air will consume more energy.
Are energy saving fans worth it?
Yes! Fans that have DC motors use less energy than AC motors. Fans with smart controls and adjustable speed settings can also save you money on electricity.
