Leds Emerge As The New Wave In Energyefficient Lig
All around us are devices with tiny lights from the alarm clock that you knock off the table every morning to your camcorder. These lights answer our most basic status questions. What is the time? Is your cell phone charging? Is it your turn to get on the freeway during rush hour?
From these little signals to your local stoplights, LEDs act as little communication runners between external systems and our brains. Around the house, you'll find LEDs used for display lighting, task lighting, nightlighting, recessed lighting, stairway and landscape lighting. Under cabinet lighting is now the most popular use for LEDs in household interiors. Aside from these mundane yet significant functions, LED's can be spectacular like the Times Square New Year's Eve ball and Beijing's GreenPix Zero Energy Media Wall. The latter has debuted as one of China's new architectural-technical gems in this year's Beijing Summer Olympics. The wall of LEDs recharges using photovoltaic solar cells during the day and lights up in the evening. It is completely carbon-neutral.
LED is short for light emitting diode. An LED unit creates light by passing a current though a semiconductor chip. A driver modulates the current (similar to a ballast in a fluorescent fixture) and keeps the LED system running. Most importantly, LEDs belong to an emerging technology called solid-state lighting. The Department of Energy has established a program called the ENERGY STAR Solid-State Lighting (SSL) Program that launched as recently as September 30th, 2008. It's a two-phase program that immediately establishes the commercial ENERGY STAR status for certain market-ready products. Phase two establishes a more rigorous performance program for future products. Now, anyone can go to a Sears appliance center and buy LED products with confidence.
The corresponding L Prize is a vital catalyst for spurring competition and innovation in the lighting industry. In the DOE's own words, "The L Prize competition challenges the lighting industry to develop high-performance solid-state lighting products to replace the common light bulb." Like it did with High Definition broadcasting, the federal government is in the process of establishing solid-state lighting as the new common lighting.
It is estimated that in two to four years, the efficiency of LEDs will exceed most of the current technologies. The perks of LED's are their small size, durability under extreme cold weather conditions, zero output of ultra violet or infrared lights (won't attract insects), zero mercury, long life, dim ability, stable frequency, varied color options and immunity to vibrations. The cons of LEDs are their current expense, heat sensitivity (extreme heat lowers their efficiency), limited directional lighting, and the grouping of LEDs reduces their overall lumen output.
A few new products on the market are illuminated shelves, wall washers, pendant fixtures and a switch plate cover.
When you're ready to purchase LED's, ask these questions:
What is the color temperature?
What is the lumen output?
What is the lamp life?
Is there a lifetime warranty?