SEATTLE — This city has a noble notion of itself at the leading edge. Its jets, coffee, computers, environmental activism and philanthropy have all been celebrated for remaking the globe.
Now Seattle wants to change not just the world but its light bulbs, too.
“I want to see what the future will be,” Steven Thompson said, carrying a questionnaire and a load of curiosity as he turned his eyes toward the sky above a normally busy but now silent thoroughfare in the city’s Ballard neighborhood one night last week, “and to have some voice in that future.”
Enlisted by a consortium of power companies, consultants, the Department of Energy, the Seattle Department of Transportation and Seattle City Light, Mr. Thompson and about 300 people were paid $40 each to spend an evening engaged in a civic version of the kind of debate that has taken place in households for some time now: what kind of light do you prefer: old and yellowy or a new and cool white?
In this case, they were judging the light provided by groups of new L.E.D. streetlights strategically interspersed among older high-pressure sodium bulbs.
Unlike domestic disagreements over the glow of a bedside reading lamp, the surveys Mr. Thompson and others filled out consider public safety — respondents are asked to agree or disagree with statements like “It would be safe to walk here, alone, during darkness hours,” “I cannot tell the colors of things due to the lighting” and “The lighting enables safe vehicular navigation.” And their answers could affect how cities everywhere are illuminated.
Utilities want to know whether L.E.D. streetlights, tens of thousands of which have already been installed in parts of many cities, including Seattle and Los Angeles, are a promising long-term technology that could shape large government contracts. Municipalities want to be sure that the significant savings in energy and costs L.E.D.’s can provide are sustainable enough to compensate for startup costs, but also that they do not threaten public safety or urban ambience.
Seattle is the fourth city to participate in the survey, following Anchorage, San Diego and San Jose, but it is hard to imagine the others being as enthusiastic.
“The big difference is you’re talking not only about the efficiency of the change in technology, but also the quality of light,” said Scott Thomsen, a spokesman for Seattle City Light, which claims to be the nation’s first carbon-neutral utility, largely because most of its power comes from hydroelectric dams.
As surveyors strolled the sidewalk, the 15-block stretch of 15th Avenue was closed to traffic so that a test car could drive up and down at 35 miles per hour, over and over, carrying passengers who pushed buttons whenever they saw certain markers placed in the street. The passengers, like the strollers, were gauging visibility in different lighting variations. Over the course of the night, lights were dimmed to test how low they could safely go.
In one area, L.E.D.’s were angled slightly so that their light shone just ahead of where drivers were going, as opposed to straight down. That was an experiment intended to address a concern that L.E.D.’s sometimes scatter light in wet conditions. Seattle was expected to be perfect for testing this solution, except that on this particular night the customary maritime mist gave way to gorgeous skies and a bright, full moon.
“We made all kind of contingency plans for the exact opposite,” said Todd Givler, one of the consultants leading the testing.
(Mr. Givler was among several people on site inclined to describe even the moon in terms of “foot-candles.” Some had been members of the influential Illuminating Engineering Society of North America, which is being watched closely to see if it will alter its recommendations for streetlights based on the L.E.D. testing.)
The dry weather forced organizers to wet the street with tank trucks that the city usually uses to flush out downtown alleys. On Thursday night, the empty avenue became a shimmering blend of moonlight, different shades of streetlights and the occasional burst of neon emerging from the Love Zone, Sands Showgirls and the T-Bird Tavern.
At one point a young man walked out onto an apartment deck overlooking the strangely silent street. He raised a beer to the light brigade below, and slurred, “On a scale of 1 to 10, can you see me?”
“Yes,” everyone replied.
