Home Energy Savings | August 5, 2016

How to Use Fans to Lower an Energy Bill

Summer is well underway and people across the state of Texas and the rest of the country are trying to figure out how to stay cool without having their monthly energy bills go through the roof. Many of us rely on air conditioning. In Texas, air conditioners account for 18% of home energy use, according to the U.S. Energy Information Administration.

Fans can also help us keep our cool — literally. Cooling with fans properly can either eliminate the need for air conditioning entirely as a cost-effective alternative, or help reduce the amount of time you use air conditioning, which in turn can help lower your energy bill. Ceiling fans generally cost less than one cent an hour to run. By contrast, Michael Bluejay, aka “Mr. Electricity,” says that air conditioning can cost up to 70 times more to run than a fan.

The issue is that many of us actually assume we know how to use fans. Stick them in a window or attach them, in the case of ceiling fans, to the ceiling, and we assume we’re good to go. Maybe yes, maybe no. Here are some ways to make sure you know how to use fans smartly.

What are different options for cooling with fans?

  • Whole house fans offer cooling systems for the entire home. Yes, there’s a large initial investment in set-up, but if you don’t want to use air conditioning, whole house fans offer an easy way to cool your entire room efficiently.
  • Ceiling fans circulate the existing air in the room. The key here is to remember that ceiling fans can only help in the room in which they’re located. That means installing a ceiling fan in every room where you want heat relief.
  • Window fans work to quickly push air in and out of the house. A fairly inexpensive solution, window fans can circulate air within a room or the entire house, depending on how you set them up.

The reality is that successfully cooling with fans is admittedly a little more complicated than simply pushing a button on an air conditioner. Window fan direction, for instance, matters when figuring out the best way to cool a room. How to use a whole house fan, meanwhile, is a mix of art and science. Here’s what you need to know about how to use fans to lower an energy bill.

How to use a whole house fan

In order to understand the benefits of a whole house fan, it’s important to understand the difference between whole house vs. attic fans. Whole-house fans are large, vented fans that mount in the ceiling on the upper floor of a house between the living space and the attic. Attic fans only cool the attic. They pull cooler outside through attic vents and push hot air outside. Attic fans also lessen the effectiveness of your air conditioning, Bluejay says, by drawing cool air from the living space into the attic if the attic doorway isn’t well sealed.

Here are the best ways to achieve all the benefits of a whole house fan:

  • Operate the whole house fan at night when the air is cooler. Whole house fans draw in fresh air from open doors and windows into the attic, where it is pushed out attic vents. Result? A cool breeze through your house and the elimination of hot air that gets stuck in the attic.
  • Choose the right size whole-house fan. A whole-house fan, says Energy.gov, can cool an entire house using less energy than air conditioning. To achieve that, however, the fan must be the right size. Whole-house fans are sized based on their cubic feet per minute of cooling power. Energy.gov has a formula for right-sizing your fan to achieve the full benefits of a whole house fan. Learning how to use a whole house fan can make a huge difference in your energy consumption, so it’s worth the time to do your research!

How to use ceiling fans with air conditioning or alone

Let’s start our “how to use fans” guide with ceiling fans. Versatile in their use, ceiling fans can cool a room by themselves or be used with air conditioning to potentially lower energy costs.

  1. Understand how ceiling fans work. Ceiling fans help cool a room by creating a wind chill effect. The cool air evaporates perspiration, which makes you feel cooler. It might be all you need on a particular day. If you decide you also need air conditioning, though, the ceiling fan’s cool breeze can let you set the thermostat a few degrees higher.
  2. Pay attention to ceiling fan direction with air conditioning. Energy.gov has some good advice about this: The ceiling fan should move in a counterclockwise direction in the summer months. It’s easy to see if the ceiling fan direction is correct. Simply stand beneath it. You should feel a cool breeze.
  3. Pay attention to ceiling fan direction with heating, too. In the winter months, Energy.gov recommends reversing ceiling fan direction and operating the ceiling fan at a low speed. This creates a small updraft, which forces warm air from the ceiling down to where everyone is living. Doing this can also enable you to lower your thermostat in the winter months. One exception to this winter strategy is if the ceiling fan is mounted in a vaulted or two-story cathedral ceiling. At that point, it is too high to create any discernible wind chill and can stay in the summer counterclockwise position year-round.

Ceiling fan direction with air conditioning

The best ways to use window fans

Window fans are another option for cooling with fans in the summer. Bob Vila, a well-known home improvement TV host, offers some tips for the best ways to use window fans successfully.

  1. Pay attention to window fan direction. Ideally, he says, one fan should be aimed to blow hot air out of the room while one pulls air into the room. Vila recommends having an equal number of fans blowing in each direction.
  2. Choose the right placement for your window fans. Fan position matters when deciding the best ways to use window fans for cooling. Vila advises placing inward-blowing fans on the shady side of the house and outward-blowing fans on the sunnier side. The only exception, he says, is if the window fans are on the ground floor in a multiple-story home. In that case, the fans on the first floor should pull in hot air while the upper-level fans push out the rising warm air. This works particularly well in the evening; as the outside air cools, the ground-level fans pull in cooler air, while the upstairs fans push out the warmer air from the house.
  3. Choose the right size window fan. Size matters when trying to figure out the best way to use window fans in your home. Vila recommends choosing the largest window fan that fits your windows. He also suggests blocking any air cavities that might exist on either side of your window unit for optimum efficiency. Some window fans come with seals for this purpose.

Two final points to keep in mind for how to use fans to lower an energy bill:

  • Window fans never lower humidity. For that, you definitely need air conditioning.
  • Shut the ceiling fan off when the room is empty. Fans cool people, not rooms.

If all else fails, you can still pick an air conditioning unit to use in specific rooms.

Comments ( 4 )

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John Fisher - 10/12/2016

How do you reverse the direction of ceiling fans? Is it the little sliding switch on the side of my fans? Or what?

Thank you.

    StarTex Power Community Team - 12/15/2016

    Great question, John. Without seeing the actual switch on your fan, I can’t say for sure, but I think that’s a good start. Most models have either a small switch or pull cord from the base that is used to switch direction. If that doesn’t work, you could check your owner’s manual or online instructions. Thanks for reading!

Velocia Ulmer - 10/31/2016

How is the direction of a ceiling fan changed?

    StarTex Power Community Team - 12/15/2016

    Hi, Velocia. Great question. Usually, a fan will have either a little switch or pull cord near its base that you can use to switch direction. If you aren’t able to find it, check your owner’s manual or online instructions. Good luck!

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