A compact fluorescent light (CFL), also known as a compact fluorescent lamp or energy saving light, is a type of fluorescent light. Most of today’s CFLs are designed to replace an incandescent light bulb and can fit into most existing light fixtures formerly used for incandescent bulbs.

There are two main parts in a CFL: the gas-filled tube (also called bulb or burner) and the magnetic or electronic ballast. An electrical current from the ballast flows through the gas (mercury vapor), causing it to emit ultraviolet light. The ultraviolet light then excites a phosphor coating on the inside of the tube. This coating emits visible light.

Compact fluorescent bulbs use approximately 75% less energy than their incandescent bulb equivalent. For example, a 7-watt CFL is generally equivalent to a 40-watt incandescent bulb. Of course, this saves you money in energy costs as well as helps protect the environment.

Also, CFLs will usually give off less heat than incandescent lamps – saving you money on home cooling costs.

Compact fluorescent light bulbs will also last much longer than incandescent lamps – up to 10 times longer! Many CFLs will last up to 10,000 hours or up to 9 years! That can mean much more time in-between light bulb changes. A big deal if you have high ceilings! And, of course, it will save you money on frequent bulb purchases.