LED Technology Illuminates a Path to the Future
LEDs, or light emitting diodes, are making inroads across U.S. society. They're even appearing in some Christmas decorations. The technology is gaining favor because the lights last longer and use less electricity. The downside is that they cost more to buy.
STEVE INSKEEP, host:
Christmas lights are getting a little greener this year, thanks to energy saving technology. The city of Denver, for example, is using light-emitting diodes for the first time to decorate its city and county building. LEDs use a fraction of the power that traditional light bulbs do.
LED makers are getting a boost from the world's biggest retailer. Here's NPR's Scott Horsley.
SCOTT HORSLEY: It started with stoplights, and it probably won't stop there. Old-fashioned stoplights are big energy wasters. They squander more power as heat than light, and what little light they do produce is largely blocked out by red and green filters.
That's why in recent years most of the nation's old-fashioned traffic lights have been replaced with light-emitting diodes, semiconductors that produce red or green light when current passes through them. LEDs last longer than traditional light bulbs and use about one-tenth as much electricity.
Now LED manufacturers are setting their sights on the rest of the lighting market. At a recent industry conference in San Diego, CEO Chuck Swoboda of the Cree Company noted that lighting consumes more than 20 percent of all the electricity in the United States.
Mr. CHUCK SWOBODA (CEO, Cree Company): I don't see, really, any lighting application that LEDs can't penetrate to some extent. And if energy matters -and I think most people now understand it does - this is probably one of the most straightforward things we can do.
HORSLEY: LEDs are already getting a green light from one big customer, Wal-Mart, as part of the retailer's effort to cut in-store power consumption by 30 percent. Vice President Charles Zimmerman says beginning next month, Wal-Mart will be installing LED lights in the refrigerated grocery cases of every new store it opens.
Mr. CHARLES ZIMMERMAN (Vice President, Wal-Mart): It'll save us about 1 and a half percent of our total energy load, which may not sound like a lot. But we purchase of about a billion dollars of electricity a year, so it is a lot.
HORSLEY: Within five years, Zimmerman expects LEDs will supply most of the light in Wal-Mart stores and parking lots. While the upfront costs can be four or five times higher than traditional lighting, he says LEDs quickly pay for themselves in lower energy and maintenance bills.
What's more, Wal-Mart's vast purchasing power should help lower the cost of LEDs. Stanford economist Jim Sweeney, who studies energy efficiency, says where Wal-Mart leads, others will likely follow.
Professor JIM SWEENEY (Economics, Stanford University): They may be the single largest user of electricity in the entire U.S. economy. It pays for them. And Wal-Mart, I don't think, ever has been accused of making decisions to just look good. They care about the bottom line. And the fact that they are so aggressive about energy efficiency should be something that other businesses and people take note of.
HORSLEY: The auto industry is already using LEDs in brake lights. And some new car models will sport LED headlights. Producing white light for headlights or homes is a bigger challenge for the technology, but performance is improving and getting cheaper every year.
It could take decades for LEDs to replace traditional light bulbs, and economist Sweeney says even then they won't single-handedly ease the nation's power crunch. But, he says, every little bit helps.
Prof. SWEENEY: I think if we deal with energy problems, particularly on the demand side, there are no silver bullets. We may have some silver buckshot. This could be a bit of a silver buckshot.
HORSLEY: Sweeney notes that for all the talk about increasing green supplies of electricity, improving efficiency by just 10 percent would free up more energy than a tenfold increase in solar and wind power combined.
Scott Horsley, NPR News, San Diego.
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