Is LED conversion a bright idea?
Sparks test runs LED street lights to save energy and money
When the city of Sparks created its Sustainability Action Plan last September, some of its goals included expanding the urban forestry program, moving toward single stream recycling, and converting street lights to light emitting diode, or LED, lighting.
Then they had to cut the budget. Then they had to cut it again. And again. For the 2008/09 fiscal year, nearly $1.1 million has been reduced from the general fund, and 38 positions have been removed or left unfilled in the Public Works Department alone. And the urban forester who was supposed to expand the “Tree City’s” urban forestry program? That person was laid off in January, too. Meanwhile, the city of Sparks last year had a street light power bill of just over a $1 million.
“Rather than lose more bodies, I’d rather reduce the bill,” says deputy public works director and city engineer Peter Etchart.
One goal of the sustainability plan is being put into play this week at the intersection of Vista Boulevard and Wingfield Hills Drive: a test site for LED street lights. They’ll be replacing 250-watt high-pressure sodium (HPS) bulbs with 72-watt LED bulbs.
Since 1995, Sparks has replaced 1,250 incandescent traffic signal lights with LED bulbs, reducing energy use by five to six times. The city expects similar savings to come from converting the street lights to LED.
But LED technology has yet to prove itself. NV Energy doesn’t accept LEDs on its approved list of street lights. An “advice letter” dated June 2008 from NV Energy (then Sierra Pacific) says LED street lights are less efficient than the high-pressure sodium lights currently in use and have lower life expectancy rates. However, the utility company also said it expects LED to surpass HPS lights in both of these areas by 2015. Etchart believes the technology, which is changing and improving rapidly, will be up to speed much sooner.
LEDs are more expensive than standard traffic lights, but they’re also between 50-80 percent more efficient, and Etchart expects about a 60 percent power bill savings from them.
“I’m hoping we can save hundreds of thousands of dollars,” he says.
The test run costs the city nothing, as Cyclone Lighting is providing the lights for free. Based on the data resulting from what Etchart expects to be about a one-year trial period, the city will research grant funding possibilities. They’re also cautiously optimistic about what the anticipated national economic stimulus plan could help provide. Sparks would also need to show NV Energy that an LED light conversion would be worth it. “If [NV Energy’s] assumptions are correct, then we wait,” says Etchart. “We want to make certain it’s proven before we do this [on a large scale.]”
Sparks’ capital projects coordinator Andy Echeita says that, in addition to the LED trial, the city is also pinpointing redundant lighting—lights that could be removed without leaving significant dark patches—and identifying lights that could be turned off, such as those in planned developments where homes haven’t been built yet. The city is also discussing using digital clocks on street lights and, in certain areas, setting them to turn off earlier than they do now. Those actions, he says, are an “instant power bill savings.”