To change the bulbs in the 60-foot-high ceiling lights of Buckingham Palace’s grand stairwell, workers had to erect scaffolding. So when a lighting designer two years ago proposed installing light emitting diodes, or LEDs, an emerging lighting technology, the royal family readily assented.
The new lights, the designer said, would last more than 22 years and enormously reduce energy consumption and carbon dioxide emissions — a big plus for Prince Charles, an ardent environmentalist. Since then, the palace has installed the lighting in chandeliers and on the exterior, where illuminating the entire facade now uses less electricity than running an electric teakettle.
The palace is part of a small but fast-growing trend that is redefining the century-old conception of lighting, replacing energy-wasting disposable bulbs with efficient fixtures that are semi-permanent.
Studies suggest that a complete conversion to LEDs could decrease carbon dioxide emissions from electric power use for lighting by up to 50 percent in about 20 years. A recent report by McKinsey & Co. cited conversion to LED lighting as potentially the most cost-effective of a number of simple approaches using existing technology to tackle global warming.
LED lighting was once relegated to basketball scoreboards, cell phone consoles, traffic lights and colored Christmas lights. But as a result of rapid technology developments, it is poised to become a staple on streets and in buildings, as well as in homes and offices. Some American cities, including Ann Arbor, Mich., and Raleigh, N.C., are using the lights to illuminate streets and parking garages, and dozens more are exploring the technology. The lighting adorns some Renaissance hotels, a corridor in the Pentagon and a green building at Stanford.
LEDs are more than twice as efficient as compact fluorescent bulbs, currently the standard for greener lighting. Unlike compact fluorescents, LEDs turn on quickly and are compatible with dimmer switches. And while fluorescent bulbs contain mercury, which requires special disposal, LED bulbs contain no toxic elements and last so long that disposal isn’t an issue.
“It is fit-and-forget-lighting that is essentially there for as long as you live,” said Colin Humphreys, a Cambridge University researcher who works on gallium nitride LED lights.
The switch to LEDs is proceeding far more rapidly than experts had predicted just two years ago. President Obama’s stimulus package, which offers money for “green” infrastructure investment, will accelerate that pace, experts say.
Sales of the lights in new “solid state” fixtures — a $297 million industry in 2007 — are likely to become a near-billion-dollar industry by 2013, said Stephen Montgomery, director of LED projects at Electronicast, a California consultancy.
Still, there remain significant barriers to LEDs. Homeowners may balk at the high initial cost, which lighting experts say currently will take five to 10 years to recoup in electricity savings. An outdoor LED spotlight today costs $100, as opposed to $7 for a regular bulb.
Another issue is that current LEDs provide only “directional light,” not a 360-degree glow.
And in the rush to make cheaper LED lights, poorly manufactured products could erase the technology’s natural advantage, experts warn. LEDs are tiny sandwiches of two different materials that release light as electrons jump from one to the other. The lights must be carefully designed so that heat does not damage them, reducing their lifespan from decades to months.
Yet nearly monthly scientific advances are addressing many of the problems.
“This is a technology on a very fast learning curve,” said Jon Creyts, an author of the McKinsey report, who predicted that the technology could be in widespread use within five years.