What is an LED?
An LED is a light-emitting diode ~ a small solid-state semi-conductor chip, encapsulated in a silicon epoxy, which emits light when partnered with an electrical current. First introduced in the 1960s in red, yellow and green, they were used mainly in appliances and digital clock displays. The blue LED was developed in 1994.
Why is the color of an LED important?
Once scientists developed the blue LED, they had the three primary colors and they could produce a white LED. Color temperatures reflect the warm (red) or cool (blue) quality of light. Currently most LEDs measure towards the cool end of the spectrum, just the opposite from warmer incandescent colors that we are accustom to. In the last few years many examples of warm LEDs have been introduced, these tend to be less efficient than the cool blue LEDs.
Is there an equation to compare LED to incandescent watts?
Unfortunately, there is not a simple formula to convert an LED light output into an incandescent equivalent. It depends on the LED manufacturer and color temperature of the lamp. Here is a general rule-of-thumb: incandescent emits 15-30 lumens per watt, compact fluorescent emits 40-60 lumens per watt, and linear fluorescent emits 60-80 lumens per watt. Depending on the quality of LED, they currently fall in the 40-60 lumens per watt category; this of course is suggestive and is ever changing as is LED technology.
Are LEDs safe?
Unlike fluorescents, LEDs do not contain mercury. They do not emit harmful UV rays like fluorescent and incandescent light sources do. LEDs don’t generate as much heat as an incandescent bulb. Anytime an electrical current passes through a material, heat is produced as a by-product. LEDs do produce heat that can reach above 212 degrees; therefore good fixture design is well-warranted.
How long do LEDs last?
The information varies from one manufacturer to another; generally LEDs will produce light for tens of thousands of hours over their lifetime. As a result, they require very little maintenance.