Quick summer tip to save you a little money: There's no point in leaving a ceiling fan on unless someone's in the room. Here's why . . .
Fans in general don't cool the air off. They just cool YOU off. So if you leave them on when you're not there, you're just wasting electricity.
Your body cools itself off through the evaporation of sweat. And when air moves across your skin, that happens faster. It also carries heat away from your body. So fans actually cool you down in two different ways.
They don't change the temperature of the air itself though. So unless you're in the room with the fan blowing on you, they don't do much.
The one exception is when you've got a window or door open, and a fan is helping to move new air in. The motor gives off a little heat though. So in some cases, it could actually raise the temperature of the room.
Pets are another reason you might want to leave a fan on when you're not home. Moving the air around cools them down too.
Last tip: You've heard this before, but people forget to do it: Make sure to switch your ceiling fans so they spin COUNTER-clockwise in the summer.
It pushes the cooler air down. If they're running clockwise, they can make a room feel even warmer. (Verify)