It's easy to dismiss the magnitude by which electric fans control our lives, but even in the digital era, this world couldn't turn without the power of electric fans. Airplane propellers and jet engines are based on technology for different types of fans. Cars and even computers can experience catastrophic failure should their fans fail. But come summer, it's beating the heat we most associate fans with.
How Do Electric Fans Work?
Fans move air thanks to spinning blades attached to a rotor on a shaft, which is serviced by a motor powered by either AC or DC electrical current. The rotor spins the blades, and speeds can usually be variable. How many speeds a fan has is far less important than the revolutions per minute combined with the number of blades and their length, which ultimately affects the number of cubic feet of airflow achieved in a minute.
By circulating air but not using a coolant, fans are environmentally friendly and energy efficient. If in use alongside heaters or air conditioners, they're proven to lower energy costs. In heating applications, a ceiling fan on low can help ensure the heat circulates a room rather than rising to the ceiling.
In hot weather, studies show using ceiling fans in addition to air conditioning can mean being able to raise the AC setting by a minimum 4 degrees Fahrenheit for the same "cool" room, causing considerable savings on electricity.
Three Types of Fan Technology
While it looks like there are countless kinds of fan technology thanks to the endless variety of models we have to choose from, there are just three technologies in use.
Axial Fans: Axial fan movement goes all the way back to early windmill design; whether powered by nature or electricity, wind moves the blades and propels air. The blades are positioned around an axis that rotates, and they pull in the air parallel to the axis and push it out the same way. It's a low-pressure airflow and is energy efficient.
Centrifugal Fans: Invented in 1832, this fan has blades perpendicular to the airflow, with many blades mounted on a flywheel that spins at high speeds and pushes air out in a radial direction, usually on a 90-degree angle from where the air enters. Usually, tubes or shafts are used to channel this airflow. An everyday example of a centrifugal fan is a leaf blower.
Industrial fans and heat blowers used in construction to speed up drying for plaster or in flood mitigation also tend to be centrifugal blowers. Engines on jets and other machines use centrifugal force as well.
Bladeless Fans: Dyson blew the doors off the small appliance world with its release of the first bladeless fan in 2009. Technically, though, they do have blades — they're asymmetrical, small blades in the base of the unit where the air is sucked in and then forced up and out through a hoop that "multiplies" the air. The effect is an outgoing airflow up to 15 times more powerful than the air sucked in, and it's also a smooth, steady flow versus the "chop" flow of a traditional axial fan. This makes for an extremely powerful, energy-efficient fan that's also much safer for households with children and pets.
Facts About Fans: Early Inventions
At The Fan Museum in Greenwich, England, they celebrate the hand fan. In artwork dating as far back as 3,000 B.C., there are depictions of ancient Greeks, Romans and Etruscans being fanned. Bird feathers were used to cool down through hand fanning by ancient Aztecs and other civilizations in the ancient Americas. Folding and fixed fans adorned with decorations and paintings became status symbols for the rich throughout history, right up into the 19th century.
When it comes to the history of fans, the first truly mechanized fan, the punkah, was created in the 1500s in the Middle East and was a canvas-covered wood frame affixed to the ceiling where it was moved back and forth via pulling a rope done by servants called punkah wallahs.
When the industrial revolution roared in the 18th century, fans began evolving. Using water wheels and fan belts, large fans were automated for the first time. But the game was afoot and change came fast and furious for fans from the 1830s on.
The Rise of Household Electric Fans
Thanks to the harnessing of electricity by Thomas Edison and Nikola Tesla, the race was on to create household convenience appliances. 1882 was a banner year for fans for the home because both the desktop fan and ceiling fan were invented by different men. A two-bladed personal-use desktop fan was created by Schuyler Skaats Wheeler and the ceiling fan was the brainchild of Philip H. Diehl, now considered the father of the modern fan.
In 1932, everything changed when Emerson introduced the Art Deco-style "Silver Swan" fan, designed by Jane Evans. For the first time, fans went beyond simple utility and became a thing of beauty. Made of aluminum, the blades emulated the shape and style of a yacht propeller. The Silver Swan is credited with helping Emerson survive the Great Depression, and it's this iteration that influenced many of the fans of the last century — even becoming trendy again, with reproductions selling for over $300 in some home decor shops today.
Buying a Household Fan
When buying a fan for the house, think about what you're looking for, where you're using it and when you'll use it. From tabletop fans to large box fans and pedestal styles, there's a lot to choose from on today's fan-buying market.
If you've got kids or pets, you'll need a child-proof grill on the fan, and it'll have to be pretty sturdy so it doesn't get knocked over. (Tower fans can be great in homes with kids and pets, and so are bladeless fans of any style or dimension.)
Box Fans: These are true workhorses and typically well priced for the power you get. They're unglamorous, just large boxes that frame the fan's blades. Because they're self-supporting and more stable to use, their size makes them perfect for positioning in windows or for use in large rooms where ceiling fans aren't possible. They're forward facing, can't be adjusted for angle and can be loud.
Pedestal Fans: With an adjustable-height pedestal, these often have oscillating heads, spinning to cover a wider area. When powerful, they're great for large rooms and for entertaining a crowd looking for a breeze. They're perfect if you're looking for higher airflow where there's no table or desk for the fan to sit on.
Table Fans: Smaller, portable, convenient and affordable, these are ideal when looking for cooling close at hand. Set it on a table nearby for watching TV or napping and take it wherever you go in the home. It can be a relationship saver when couples prefer different home temperatures.
Floor Fans: Up there with box fans for efficiency, if not even better, floor fans are designed for power and impact in spaces without ceiling fans. Unlike box fans, they're usually angled for superior air movement despite their low profile.
Tower Fans: The most recent of air movers, these can often come with bells and whistles like ionizers, which help freshen the air. They're typically more stable and, therefore, less likely to tip over. They're great in large rooms, but their size and slim profile also make them ideal for small rooms. An added plus is that they're often far quieter.
Window Fans: Great for places where air circulation needs improvement. These are fitted into a window and used to draw fresh air in while pushing hot or stale air out.
Ceiling Fans: What to Look For
Invented in 1882, ceiling fans are one of the few inventions of the 1880s that haven't dramatically changed in their 130-plus years despite catching on worldwide. Travel in tropical climates from the Caribbean to Southeast Asia and India, and you'll find ceiling fans omnipresent. Even in places that can afford the luxury of air conditioning, ceiling fans are often still used to get the most out of the cool air.
Their effectiveness isn't just limited to cooling the skin and beating the heat, though. Anyone who's hung out in a tropical grass hut with a beverage in hand can tell you how an overhead fan makes it the best place to sit under for keeping mosquitoes at bay.
When buying a ceiling fan, here are some tips to consider:
- Look at the CFM. This stands for "cubic feet of airflow per minute," and it's how they rate how cool a fan can keep you. Look for a minimum of 6,000 CFM with a fan that's meant for your room's size.
- Get the right size fan. Blade length is everything because the longer a blade is, the more airflow it creates. For a bedroom-sized room of around 100 to 150 square feet, you'll want a blade span of 44 to 50 inches. For a large room of around 300 square feet, you want 62 inches or greater. In between 150 to 300 square feet, get a 52- to 62-inch blade span.
- "Less is more" with blades. A fan with four or five blades will have more drag and be less energy efficient, plus move air less well. The ideal is a three-blade fan, like with wind turbines, which are highly effective. Plus, you'll need blades angled around 12 to 14 degrees for the best performance.
- Get a light and save on energy! Strangely, light-combo ceiling fans aren't just more convenient for offering overhead light and coolness, they're also as much as 60 percent more energy efficient, possibly even more so when Energy Star rated.
Using Fans in Heat Waves
Most people don't get the most out of their electric fan when summer's heat is beating down on them. It's important to remember that the primary purpose of a fan is to move air, not cool you off. If you turn to this basic principle of what fans do best, you can see a shocking difference in how your apartment feels in the dog days of summer.
A box fan works best for this, and the closer the fan is to the same width of the window you're using, the better success you'll have. Position the fan in, or by, an open window with its current blowing out the window. It sounds nutty, but the premise is, the fan sucks the hot air out of the room and cool air takes over. In just 10 or 20 minutes, you'll see the heat drop considerably in a room. This works especially well when getting home late in the evening while the afternoon's swelter still lingers in your place.
Some people swear by having a bowl of ice in front of a fan to blow "cold air" at them. This can be effective, but be sure you don't use dry ice in a closed room because it causes CO2 when it evaporates, and breathing it can make you drowsy or even be lethal over time. Instead, use typical fresh-from-the-freezer ice, and make a nice beverage while you're at it.