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.
energy efficient products
ENERGY STAR products are independently certified to save energy without sacrificing features or functionality. Saving energy helps prevent climate change. Look for the ENERGY STAR label to save money on your energy bills and help protect our environment.
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energy savings at home
Improving your home's energy efficiency with ENERGY STAR can help to lower high energy bills, improve comfort and reduce greenhouse gas emissions. Learn about the many ways to save in your home and track your progress with "My ENERGY STAR" - your new dashboard to savings.
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energy efficient new homes
A new home that has earned the ENERGY STAR label has undergone a process of inspections, testing, and verification to meet strict requirements set by the US EPA. ENERGY STAR certified homes use 15-30% less energy than typical new homes while delivering better comfort, quality, and durability.
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ENERGY STRATEGIES FORbuildings & plants