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s manager of Seattle City Light’s Streetlight Engineering Unit, Edward Smalley leads the utility’s planning and R&D as it prepares for the “next generation of street lighting technologies.” That assignment sounds rather lofty and futuristic, doesn’t it, like a sci-fi story—Star Trek Meets Seattle. Well, guess what: the “next generation” of street lighting has already arrived, and Smalley is now carrying out a four-year plan to replace 40,000 streetlights on residential streets—nearly half the city’s 84,000 streetlight inventory—with LED luminaires.
This year, during phase one of the project, more than 5,000 lights will be installed, while plans for the replacement of streetlights along arterial streets and decorative fixtures will be developed by the end of 2010. “Once all the LED fixtures are installed, they are expected to save 36 million kilowatt-hours of electricity each year, a 40 percent savings [over current usage],” says Smalley.
The long road to 40,000 new fixtures began with pilot projects. Currently, there are 150 LED streetlights in place within 14 pilot/demonstration areas; some of these installations, however, have received less than glowing reviews from the local populace. As Seattle lighting designer Daniel Salinas noted in the September 2009 issue of LD+A, “. . .Seattle is currently running tests of LED street lighting in neighborhood areas and soliciting comments from the citizenry. The results are not necessarily in LEDs’ favor when you read some of the comments, mostly having to do with glare and color. But the voices in favor of LED street lighting—using energy efficiency as their main sticking point—tend to be louder than those of the majority.”
Seattle has historically lived on the green edge, so with that in mind, Smalley addresses the challenges faced by early adopters of new technologies.
—Paul Tarricone
 LD+A: There is an old saying that “pioneers take the arrows in the back.” That being said, why did Seattle decide to become an early adopter of LED street lighting?
Smalley: Being an early adopter of energy-saving technology is nothing new for Seattle City Light. The utility has been a pioneer in energy conservation for more than 30 years. In the 1970s, the City Council decided to pursue energy conservation as the city’s first resource of choice for meeting load growth for Seattle City Light. The utility has been actively working to increase energy awareness and conservation ever since, including support for lighting retrofits, compact fluorescent light bulbs, home energy audits, refrigerator recycling and more. LED street lighting is a natural fit. We believe strongly that the benefits of early adoption (improved light quality, reduced energy consumption and savings in operating costs) far outweigh initial hurdles and drawbacks.
LD+A: Are LEDs for street lighting applications being oversold, and are there LED pilot projects in Seattle that haven’t met expectations?
Smalley: The pilot programs have yielded extremely useful results. We have been able to draw on lessons learned and community feedback to make improvements in fixture selection and light settings, including color, brightness and the light footprint. More than 85 percent of survey respondents replied favorably to lights installed in their neighborhoods. When reviewing the U.S. Department of Energy’s Gateway website, we find this is in line with national trends.
When analyzing citizen feedback, it is important to recall some responses to the conversions from mercury vapor to high-pressure sodium fixtures in the late 1970s and early 1980s. On a recent Seattle blog about the LED installations, one reader said, “I’ve lived in Seattle all my life. Long enough to remember the same complaining over the ‘awful’ high-pressure sodium lamps the city currently uses when they replaced whatever it was they used before then. Now people are getting all sentimental over them. Some folks just don’t like change. Others just love something to complain about.”
While the majority of comments regarding Seattle’s LED pilot projects have been supportive, there have been concerns raised by some residents regarding the color temperature. Some felt the bluer light, 5,500K to 6,000K used in our first pilots, was too obtrusive when coming through windows. Others thought the same fixtures gave off more glare than the HPS fixtures they replaced. In subsequent pilots, Seattle standardized on 4,000K temperature fixtures and has found this to be much more acceptable to residents.
LD+A: What is your assessment of the LED street lighting luminaires currently available in the marketplace?
Smalley: Many LED streetlight products on the market today meet and/or exceed roadway lighting requirements and are able to light roadways as good as or better than high-pressure sodium technology. But there also are many fixtures in the marketplace that are not suitable for use on roadways. It is extremely important that lighting designers do their homework to find the most appropriate fixture for their application. IES LM-79 and LM-80 test data is invaluable and a must-have first step to evaluating any company’s fixture.
It is as important to find a good manufacturer as it is to find a good fixture. You want to be familiar with the professional and historical reliability of those making the claims you are relying on for your decisions. With claims of 50,000 to 100,000 hours of design life, you may want to ask if the company will be here in 12 to 20 years. Where were they five years ago or one year ago, for that matter?
It’s likely the most reliable component to the LED streetlight fixture is the LED itself. With this in mind, we have placed emphasis on reviewing all components of the luminaire as well as the ingress/egress of water and dirt. We asked ourselves, “If the LEDs are to last 100,000 hours but the driver just 50,000 hours does the fixture really last 100,000 hours?”
Though the marketplace is rapidly evolving, it is very important to do our research to find the most appropriately fixture for each application.
LD+A: Aside from LEDs, are there other street lighting technologies/systems, that Seattle is pilot testing?
Smalley: While the vast majority of Seattle’s streetlights today use HID technology, Seattle City Light began testing induction streetlights in 2002. These tests were very successful in our decorative and post-top applications and today there are over 500 induction fixtures installed in downtown Seattle. In addition, Seattle is monitoring emerging technologies such as plasma lighting and improvements in other HID technology.
LD+A: What’s next?
Smalley: LEDs are an instant on/instant off technology with no start-up or re-strike time. So it is logical
that combining LED roadway luminaires with lighting control systems can potentially provide many new options
for overall light control, facilitating maintenance, increasing luminaire life, and reducing operating costs.
Seattle will next evaluate this option.
May 2010
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