ABOUT ENERGY STAR PARTNER RESOURCES

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How does a CFL work? Follow

CFLs produce light differently than incandescent bulbs. In an incandescent, electric current runs through a wire filament and heats the filament until it starts to glow. In a CFL, an electric current is driven through a tube containing argon and a small amount of mercury vapor. This generates invisible ultraviolet light that excites a fluorescent coating (called phosphor) on the inside of the tube, which then emits visible light. CFLs need a little more energy when they are first turned on, but once the electricity starts moving, use about 75% less energy than incandescent bulbs. A CFL's ballast (the electronic part that regulates the electric current through a fluorescent lamp) helps "kick start" the CFL and then regulates the current once the electricity starts flowing. Older CFLs used large and heavy magnetic ballasts that caused a buzzing noise in some bulbs. Most CFLs today and all ENERGY STAR qualified CFLs use electronic ballasts, which do not buzz or hum.

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