What Is A CFL bulb?
Compact Fluorescent Bulbs or CFLS, produce light in a different manner than standing incandescent bulbs. Rather than an electric current heating a wire filament until it starts to glow such as in a standard bulb, in a CFL, the electric current travels through a tube containing argon and mercury vapor. Invisible ultraviolet light is generate which excites a phosphor coating on the inside of the tube. The tube then emits visible light.
CFLs use almost 70% less energy than incandescent bulbs. A CFL’s ballast regulates the current once the electricity starts to flow. CFLs take longer than other bulbs to become fully lit because this process typically takes from 30 seconds to 3 minutes to complete. CFLs with reflector shapes, globes or other decorative covers can result in a slower warm up time due to their design.
Older types of CFLs used big and heavy magnetic ballasts that could cause a buzzing noise in some bulbs. Most CFLs today now use electronic ballasts, which do not buzz or hum. Look for the ENERGY STAR label certification.