Contractors for the Beijing Olympics considered fluorescent lighting for some of their key venues until they evaluated light-emitting diodes and found them to be a more colorful, lower-power route to illuminating their creations. Their efforts are likely to make a brilliant impression on millions at a time when LED technology is trying to cross a threshold in consumer applications."We can control the specific wavelength of the color to provide a very even color with low power," said Richard Sy, president of Cree Hong Kong. Cree Inc. (Durham, N.C.) is providing about 754,000 LEDs to light up the so-called Bird's Nest and Water Cube, which respectively house the opening ceremonies and water sports for the Beijing Olympics. The company's LEDs will also appear in some video and information displays at the event.The Water Cube alone uses about 440,000 LEDs to illuminate its exterior. Each eight- to 16-LED module needed to be outfitted with unique optics to focus beams on the plastic film on the outside of the building. A company from Shanghai created the controls that run the networked LED modules.The red, green and blue LEDs average an output of about 16 lumens per watt. White LEDs currently in production emit as much as 99 lm/W and ones in the lab hit 120 lm/W. By contrast, fluorescent tubes deliver about 70 lm/W.Because LEDs give off a directional light, they provide a more consistent color than omnidirectional tubes, assuming companies like Cree craft the right optics to focus those beams. And because LEDs use less power and are more durable--they don't use filaments that regularly burn out--they are making inroads into consumer applications. "Next year you will be hard-pressed to find a new flashlight that does not use LEDs," said a Cree spokeswoman.Although LEDs still carry a price premium over traditional technologies, they are starting to replace fluorescent bulbs for directed home lights such as recessed lighting. Some 10 million new sockets are going into new buildings each year, and as many as 9 million sockets are already in place, said the Cree spokeswoman. Even if sockets require a retrofit for LEDs, the technology can pay for itself with lower utility bills in one to four years, she added. p
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