There has been a lot of talk in Cleveland lately about the future of lighting using LEDs. If you are looking for a quick overview of the technology and how it compares to other lighting products, here are a few technical fun facts you should know.
A light-emitting-diode (LED) is a semiconductor material that emits light when a voltage is applied.
A diode is an electronic device that has two electrodes arranged so that electrical current flows in one direction. A diode has the ability to control the flow of electrons, and it is used to convert alternating current into direct current.
LED bulbs produce light in an entirely different way than other bulbs. Instead of using electricity to heat up a metal filament, LEDs produce light by channeling an electric current through a semiconductor material. This approach converts about 97 percent of the electricity into light, with virtually no waste heat produced. Incandescent bulbs, by comparison, use a brittle metal filament that is susceptible to shock and vibration and convert only 15 percent of the energy it consumes into light. A CFL bulb typically converts about 50 percent of the energy it consumes into light.
Incandescent bulbs are hot to the touch. LEDs are cool to the touch. (click to enlarge)
LED bulbs last 20 to 25 times longer than incandescent bulbs.
LEDs do not attract insects or emit UV rays. LEDs also do not cause fading of fabrics and surfaces.
Compared to CFLs, LEDs and CFLs both save energy and money; however, LEDs consume less energy than CFLs and last longer.
CFLs are most effective in places where they will remain switched on for long periods. CFLs typically gradually brighten and emit light to its rated value. Switching CFL bulbs off after only a few minutes of use can reduce CFL bulb lifespan.
LEDs do not have gradual lighting effects and do not suffer diminished life spans due to normal on and off switching.