Bright, White Future for "Green" LEDs, Scientist Says

March 15, 2007

Rapid improvements to the efficiency and power of light-emitting diodes (LEDs) will soon allow the decades-old technology to revolutionize how we illuminate our world, according to an industry expert.

Mass adoption of LEDs could cut global electricity use by 10 percent, said George Craford, chief technology officer for Philips Lumileds in San Jose, California.

Craford presented a review paper on the latest LED advances last Tuesday during a meeting of the American Physical Society in Denver, Colorado.

A switch to LEDs in place of conventional lighting would save "a huge amount of electricity and a huge amount of money," he told National Geographic News.

The energy savings "will amount to well over a hundred nuclear power plants worldwide."

Materials scientist Steve DenBaars directs a research center at the University of California, Santa Barbara (UCSB), that focuses on energy-efficient lighting and display technologies like LEDs.

DenBaars said that Craford's estimate of energy savings may be a slight overstatement, "but it's on that scale."

"Twenty-two percent of [U.S.] electrical energy consumption goes into lighting, and we're talking about taking the efficiency up several factors here and taking that number down to like 3 or 4 percent," he said.

By that calculation, he said, energy-efficient lighting could save the U.S. the equivalent of the power produced annually by 133 coal-fired power plants.

Technology Advances

LEDs are tiny devices made of semiconductors—solid materials such as silicon that have varying abilities to conduct electricity.

Since the 1960s scientists have known that LEDs made from different semiconductors glow at different colors when voltage is applied (see a related photo of LEDs being tested at a semiconductor factory).

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