The benefits of using a ceiling fan for energy savings date back to the 1950s as air conditioning began to be widely utilized in residences. Ceiling fans had been a home fixture since the 1920s when they became the first electric-powered comfort appliance installed in most houses. However, the later introduction of A/C did not render the graceful, slowly-rotating air movers obsolete. Instead, as energy expenses have steadily climbed, ceiling fans have continued to hold a place in home cooling. Using a ceiling fan for energy savings allows homeowners to lower A/C operating costs while still enjoying the same level of cool comfort in living spaces.
Using a ceiling fan for energy savings in summer works in two ways:
- Running a ceiling fan alone provides cooling by air circulation that can delay the time each day when you have to turn on the air conditioner for comfort. Over the course of a month, a few hours delay every day in utilizing that major electricity consumer will lower energy expenses. You can aid this effort by opening windows when the night-time and morning air is still cool, and then closing them before it gets hot.
- The ceiling fan as a complement to the air conditioner allows you to set the A/C thermostat a few degrees higher without compromising the comfort level in occupied rooms where a ceiling fan is installed.
When used correctly, ceiling fans can supplement the cooling effect of air conditioning and reduce energy costs. We’re all familiar with the wind-chill factor that makes a windy winter day seem even colder than the reading on the thermometer indicates. The movement of air over the skin increases the body’s thermal loss and makes people and pets feel cooler. In the same way, air circulation provided by a ceiling fan creates a micro-wind-chill effect in occupied rooms that augments the sensation of cooling provided by the air conditioner.
This permits the homeowner to increase the A/C thermostat setting by much as four degrees without detracting from the comfort level in the room. For each degree you bump the thermostat up, you can reduce cooling energy costs as much as 3 percent over every eight-hour period that you run the ceiling fan and the A/C together. It’s possible because of the vast difference between the energy consumption of an efficient ceiling fan versus an air conditioner: Ceiling fans typically use about 20 watts of electricity on low speed and up to 100 watts on high speed, while an A/C commonly consumes at least 3,000 watts.
Choosing The Right Fan
Ceiling fans are sized by blade length and room dimensions:
- A fan with 24-inch blades is appropriate for small rooms of 80 square feet or less.
- Blades up to 52-inches are a good match for guest bedrooms or other spaces around 100 square feet.
- Blades up to 62 inches or larger can cool more than 300 square feet in large bedrooms and dining/living rooms.
The pitch of a ceiling fan blade refers to its angle of attack as it rotates through the air. The higher the blade pitch, the more air the fan moves. When the pitch is too low, you won’t get optimum volume of air circulation and cooling effect; when it’s too high for the room size, the excessive air movement may blow papers around and disturb occupants. For most home applications, a blade pitch between 12 and 15 degrees is considered optimal.
Using A Ceiling Fan
During hot weather, the fan motor switch should be set to the “Summer” or “Reverse” setting so the blades rotate counter-clockwise. This directs air downward into the room for maximum cooling benefit.
Remember, a ceiling fan doesn’t actually lower the temperature of a room as registered by a thermometer, it simply makes the room feel cooler to human and animal occupants. This means there’s no point whatsoever to leaving a ceiling fan running in a room when nobody’s there. In fact, the cost of energy wasted by running ceiling fans in unoccupied rooms can offset the benefits of using a ceiling fan for energy savings.
For more information on using a ceiling fan for energy savings in the Bradenton area, please contact us at Aqua Plumbing & Air.
Written by John Miller
Image Provided by Shutterstock.com