by Jack Mayne
Des Moines city officials expect to save over $45,000 a year by replacing the city’s 1,021 street lights more energy efficient LED lights, a move communities all over King County and the nation have done in recent years.
The biggest complaint people have about the new lights is the illumination is bright white, not the softer yellowish light that people have grown accustomed to seeing. The objections seem to pass with time and familiarity.
Seattle City Light said Thursday it has installed LED streetlights on all residential streets throughout its service territory, about 40,000 streetlights. It is now in the process of installing LEDs on arterial roads and in commercial areas.
Des Moines’ current lights are 100-watt High Pressure Sodium (HPS) fixtures. They are to be replaced by the city’s power provider, Puget Sound Energy, over the next three years, starting at the city’s north end and moving south.
The new Des Moines streetlights will be 54-watt LED lights which the city says use about 50 percent less electricity and last nearly 20 years as compared with the eight year life of the current HPS fixture.
The current monthly cost for a HPS light is $12.02 per month or $144.24 per year and Des Moines officials say the rate for a 54-watt LED is $8.38 per month, a savings of approximately 30 percent. This savings will result in a 16 percent reduction in the overall streetlight bill for the city.
Last year Des Moines spent approximately 30 percent of the total city street fund on streetlight maintenance and electricity. The conversion to LED streetlights, the city says it would realize an annual savings of $45,253 a year, indefinitely once the conversions are complete.
The initial cost for the conversion is estimated by the city at $132,225 and “with factoring in the annual savings, the payback period would be just under three years.”
The city said that converting streetlights “from HPS to LED is a step toward reducing the city’s ongoing costs associated with street lights. This reduction of streetlight costs will allow for the savings to be redistributed to other areas in need within the street fund.”
Other places where the change has been made brought initial complaints about the bright, white light that replaced the more familiar and calming yellowish light.
During the Seattle conversion, Crosscut blog writer Eric Scigliano wrote, “Many people find this cool light unsettling, at least at first. But it also makes for truer colors.”
The article noted that living with the new light is a mixed bag.
“For some, they’re a nightmare. When the new lights arrived in Wallingford in late 2011 … the Wallyhood blog lit up with comments, from ‘a bit better than the yellowy light we used to have’ to ‘HATE the color…HATE the sharp glare…HATE that it makes everything under it look cold and blue.’”
But after a while, Scigliano noted a softening of hate softens with familiarity.
“I don’t hate them so much as I did at first,” said software engineer and light-pollution watchdog Bruce Weertman. “I actually like the white — it’s more natural.”