Do you really need that 100 watt lamp at full power all the time? You can save energy and prolong the life of your bulbs by using dimmers. Believe it or not, dimming a bulb by 15 percent can double the bulb life and shave a few dollars off your yearly energy bill. (Check out Lutron’s Interactive Dimmer Calculator to see how much you can save.) The best part, dimming by 15 percent is imperceptible to the human eye.
One caveat: Dimmers that are more than 40 years old won’t save energy, just bulb life. The old dimmers simply convert excess energy into heat.