Ed Ebrahimian loves to stare out the plane window on night flights home to Los Angeles. Next time you fly into L.A. late, take a good look and see why. Five years ago a bright orange blanket of light used to saturate the city and stain the air above. Today it’s a metropolis aglow with tens of thousands of cool silvery pinpoint lights. The grid is clearer. The skies are blacker.
“The lights look like candles now, and they aren’t glaring at all,” Ebrahimian gushes. “The sky glow is the most amazing thing I’ve seen in my life.”
Ebrahimian has good reason to be enthused. As director of L.A.’s Bureau of Street Lighting, he’s overseeing one of the largest relighting projects in the world, spending $57 million to retrofit the city’s 215,000 lights, which come in more than 400 styles. The money has gotten him only to lamppost number 155,000 after five years. Replacing the remaining 60,000, including most of the decorative ones, will cost $50 million more.
Los Angeles is a dramatic front in an important and overlooked battle facing the rapidly urbanizing world: the struggle between light and dark. Cities and businesses want more light everywhere for commercial and safety reasons, but our decades-long saturation bombing of the darkness is blowing holes in electricity budgets, confusing and killing wildlife, and completely erasing our view of the stars, the inspiration for millennia of scientists, poets and explorers. “What was once a most common human experience has become most rare,” writes Paul Bogard, author of The End of Night, a book that assails the world’s unchecked light pollution.
The technology at the center of the shift is the LED, or light-emitting diode. LEDs are a break from the history of illumination. As solid-state semiconductors, they’re more akin to the processor in your smartphone than the lamp overhead. Los Angeles, New York, Chicago, Shanghai, Copenhagen and scores of other cities around the world are deploying LEDs in an attempt to solve most, if not all, of the problems created by inefficient traditional lamps.
LEDs cost three to four times more up front than traditional high-pressure streetlamps, but they last three to four times longer and produce two to three times more light per watt, delivering anywhere from 30% to 70% in annual electricity savings. Because they are digital chips, they will only get cheaper as the efficiencies of Moore’s Law roll on. And as electronic components they’re also far more programmable and connect more efficiently with radio and sensor chips to create citywide wireless networks to monitor crime, power outages and water main breaks and coordinate disaster relief.
Original story from Ucilla Wang
Courtesy Forbes Magazine