Cooling is one of the primary functions of a ceiling fan. According to the website HomeTips, a properly installed ceiling fan can make a room that is 79 degrees Fahrenheit feel like it is only 72 degrees. This can let you turn down your air conditioning, which can save you money.
In the winter months, turning on the ceiling fan helps to force warm air downward. Since cold air tends to fall and warm air rises, this helps to circulate the air in the room and make it feel warmer. To get this effect, turn the fan on in the opposite direction that it normally runs.
Using a ceiling fan can help you cut energy costs. According to the Energy Star website, the amount of savings depends largely on proper installation and use of the fan. For optimal results, make sure the fan is properly mounted, and turn it off when you don't need it.