Unlike air-conditioning, a ceiling fan doesn’t actually make the air in a room or space cooler. Instead, the fan cools the occupants in it. The breeze from a properly sized and placed ceiling fan cools occupants by disrupting the stagnant layer of air that surrounds the body, preventing heat loss. The removal of that insulating layer of air increases a body’s heat loss to make it feel cooler.
Heat loss (cooling) can come in two forms: cool air passing over the skin removes heat via convection and relatively dry air passing over the skin increases the rate of perspiration evaporation. Learn more about evaporative cooling. Because a ceiling fan cools occupants but not spaces, it makes sense to turn off a fan in an empty room, unless air circulation is required for reasons other than comfort.
Big Ass Fans® create cooling breezes that make a person feel up to 10°F (6°C) cooler while requiring minimal power to operate. They do this by relying on size rather than speed. While spinning at a low speed the 52-in to 24-ft diameter fans move large amounts of air, efficiently providing that cooling breeze.