The city of Pittsburgh, Penn., may heed a recommendation to switch all of its streetlights from high-pressure sodium lights to light-emitting-diode (LED) lamps, according to an article in the Pittsburgh Post-Gazette. The University of Pittsburgh's Mascaro Center for Sustainable Innovation conducted a Life Cycle Assessment of Streetlight Technologies in the city and found that LEDs are the best bet environmentally when the lamp's entire life is taken into consideration. Even though the production of LEDs is not as efficient or sustainable as that of other light products, when the Mascaro study took into account energy savings as well as longevity of the product, LEDs came out on top.
According to the article, the city could reduce CO2 emissions by 6,818 metric tons per year, save $1 million annually in energy costs and $700,000 in maintenance fees with LED streetlights. Only about 1 percent of the streetlights in the country are powered by LEDs, primarily Los Angeles, Calif., and Anchorage, Alaska, meaning Pittsburgh would be a leader in adopting this technology on a large scale. The city has already installed LED streetlights in the Southside neighborhood and, as an experiment, lit one side of a popular shopping street with LEDs and the other with "other technologies." The result? The article quotes Bill Peduto, city councilman, saying, "the superior quality of LED lighting is obvious."
The LED streetlights are not without drawbacks, however. The LEDs are very bright and cast a blue-tinted light, so light pollution might be an issue. Another issue is heat, or lack thereof — LEDs don't get hot the way traditional streetlights do. In places like Wichita, Kan., this became problematic when a recent article in the Wichita Eagle reported that LED lights failed to melt ice and snow. Wichita's LED traffic lights became covered in snow, making it difficult for drivers to tell the colors of the lights, though the article said no accidents have been attributed to this problem.
The Pitt study of the lifecycle of the streetlights is one of the first cradle-to-grave studies done on urban lighting, according to the Post-Gazette, and the findings indicate that LEDs will become increasingly more efficient as the technology improves. The study "compared LED lighting with computer chips in projecting ... cost reductions for years to come."
Several subcommittees of the Pittsburgh City Council will develop a better streetlight network and, as the city is one of the few nationwide without a lighting code, will propose a Pittsburgh lighting code. Once these analyses and codes are in place, the city will make a final decision regarding the switch. At any rate, Pittsburgh hopes the research study and task force studies will serve as "a standard tool for municipalities worldwide to evaluate streetlight technologies." The city hopes to begin installation of new lights later this summer.