Hot Button: Bright Lights, Big City

Thanks to new lighting technologies, Seattle may be heading toward a brighter, more efficient future—but will it be better?

As each warm, languid summer night falls on Seattle, most of the city’s 84,000-plus streetlights flicker to life, bathing our nocturnal urban landscape in their familiar pinkish-orange light. These lamps—lit by high-pressure sodium bulbs—have come to define our city’s nighttime appearance, coloring our streets, our neighborhoods, our parks and our collective consciousness with an amber-hued gloominess that seems as natural to us as cloud cover.

But at the intersection of 16th Avenue E and E Highland Drive, something seems amiss. This neighborhood of stately homes, just a block east of Volunteer Park, is one of the city’s oldest, dating back to the 1800s. Massive maple trees tower over the streets; lawns, homes and gardens are precisely maintained; and there’s an aura of anachronism here that seems lifted from a movie set—except for the blinding streetlights, that is.

This intersection is one of nine sites on Capitol Hill chosen by Seattle City Light for the study of state-of-the-art light-emitting diode (LED) streetlights. As twilight fades from the sky, these LED lamps illuminate the street with a light as white as a tractor beam from an alien spacecraft in a sci-fi flick. Perhaps because of the whiteness of their light, LEDs are sometimes mistaken for compact fluorescent lights, or CFLs. But LEDs are an entirely different type of bulb—and with a much more efficient technology.

Despite the initial shock of its brightness, the light cast by these new lamps does make it possible to distinguish a full range of colors. Red cars appear red; green ones appear green; and yellow appear yellow. (Under Seattle’s existing sodium bulbs, specific colors are often lost resulting in general “light” or “dark” shades.)

Walking along these newly brightened streets, it’s quickly clear that Seattle City Light’s LED streetlight study may radically alter the look of our city after dark. City Light is testing six different types of LED bulbs at the Capitol Hill study sites, which vary from strictly residential (as is the case at 16th Avenue and E Highland Drive) to strictly commercial (at Broadway and Roy, for instance). The study (which concluded in July; final results were pending at press time) tested the lighting quality of the original incandescent bulbs as compared to the six types of LEDs. The technical results were then combined with a public opinion survey to determine the preferred type of LED.

But a switch to LED streetlights is far from a foregone conclusion. One of the biggest obstacles is cost: LEDs are, on average, 10 times more expensive than incandescent bulbs. And it’s not as if our fair city is awash in budget surpluses these days. But, as with the light spectrum, cost isn’t a black-and-white issue.

“[LEDs] use significantly less energy to produce the same amount of light” as the existing bulbs, says Mike Eagan, a City Light spokesman, “so there is an immediate saving in energy cost.” How much less? According to numerous studies, LEDs use as little as one-tenth the electricity of traditional bulbs, and about half the juice as those curly-headed CFLs that have made their way into homes and businesses across the city. (The energy usage of a bulb is the number of watts imprinted on the bulb. Most LED bulbs are 7.5 watts, whereas CFLs are 13 watts, and incandescent bulbs average more than 60 watts.) Another bonus: Unlike CFLs, LEDs do not contain mercury, making them even more appropriate for a city that prides itself on its awareness of environmental issues.

LED lights also last much longer than other bulbs. The lifespan of the LED streetlights tested by City Light is 15 years, while the current sodium streetlights are rated to last only five. Because the ultradurable LEDs lack filaments, they aren’t prone to early burnout. Longer bulb life will translate to fewer malfunctioning streetlights, lower personnel and maintenance costs, and lower greenhouse gas emissions from City Light’s vehicle fleet. “The bottom line is that LEDs are more energy efficient,” says Alex Fryer, a spokesman for Mayor Greg Nickels, “and we’re looking for all ways to make the city more energy efficient.” For city leaders, the issue may be whether or not the city can afford not to buy into LEDs.