LED Streetlights a Bright Idea

May 17, 2008

LED streetlights may be replacing our fluorescent and sodium standbys in upcoming years. Replacements are occurring across the U.S. as municipalities work to go green. Sweta Dash, a market research analyst from iSuppli Corp, predicts that “In the next few years we will see this major change, where LED lights are going to be everywhere."

LED lights, or light emitting diodes, are hardworking little semiconductors that that turn energy into light, the opposite way a solar cell functions.

The energy consumption of regular streetlights is glaring. The dozen largest cities in the U.S. alone host over four million streetlights that suck up three billion kilowatts of energy a year. The environmental cost is millions of metric tons of carbon dioxide, or hundreds of thousands of cars on the road. All this waste is unnecessary with LED lights, which are many times more efficient than incandescent or fluorescent lights.

Though LEDs are more costly up front, because the streetlights we are accustomed to are energy dinosaurs, they pay themselves off in less than five years.
LED lights offer municipalities other cost advantages. Never will you have the creepy flickering streetlamp with an LED light; there is no filament to burn out, reducing maintenace. LED lights are up to 10 times more efficient than incandescent lights because the heat in an LED is almost completely turned into light, not wasted as heat, so they last longer. Because LED lights are plastic rather than glass, they also are less likely to crack or shatter.

Installing LED lights can be paired with installing computer networks that respond to real-time conditions, changing the amount of streetlight as necessary. This allows cities to customize their lighting according to season, neighborhood safety, or storm conditions. To boot, the low energy cost of LED lighting makes it more feasible to fit streetlamps with mini solar cells themselves, taking them off the grid entirely.

Regular streetlights are also the culprit of light pollution -- the glow that comes from cities, so bright that it is observable by satellite. To the delight of astronomers everywhere, LED lights produce a more focused, spotlight-like beam. LED lights may also be coated with thin nanocrystals, resulting in natural seeming light rather than fluorescent’s wash-out blue or sodium’s fuzzy yellow glow.

LED lights offer an array of other benefits. Because they don’t emit UV rays, they don’t attract insects. Because their size and shape are easily manipulated, they offer significant design flexibility. This flexibility has led to advances in flat screens, traffic lights, pdas, laptops, flashlights, Christmas lights, headlamps, surgical equipment and now, your neighborhood.