City switching to street lamps that cast a white glow
BY DARRYL HOLLIDAY Staff Reporteremail@example.com August 5, 2011 11:06PM
The Chicago Department of Transportation is installing new, energy-efficient lights all over the city. The light on top is old; the light on the bottom is new. FILE PHOTO. | Brian Jackson~Sun-Times
Updated: November 16, 2011 1:22AM
The yellow-orange street lamp glow Chicagoans have become accustomed to over the years is going the way of the “pretty blue lights” of Lake Shore Drive once commemorated in song.
The blue lights along Lake Shore Drive — mercury-vapor streetlamps used into the ’70s — gave way to the yellow-orange lights currently used in most of the city, sodium-vapor street lamps. This week, however, the Chicago Department of Transportation announced it is installing new, energy efficient lighting on street lamps and traffic signals, which casts a white glow on city streets.
The new, metal-halide lights will use less energy than the current streetlamps. Chicago, according to CDOT officials, is the first large U.S. city to install the relatively new technology en masse. City officials estimate an annual $1.8 million in electrical cost savings, as well as a reduction of nearly 15,000 metric tons of carbon dioxide.
“If you’ve seen Chicago from the sky, you’ve seen the orange glow,” CDOT spokesman Brian Steele said. “It won’t be that way anymore.”
The older, yellow-orange glow will be steadily replaced by the brighter white lights, thanks to federal funding from the U.S. Department of Energy. So far, about 2,300 lights along Lake Shore Drive from 71st Street to Hollywood Avenue, nearly 3,000 lights along Western Avenue from Howard Street to 119th Street and about 300 miles of alleyways across the city are scheduled for replacement. The city started the project last year and is expected to wrap it up this summer.
CDOT unveiled a new set of the metal-halide lamps, along with new, LED traffic signals, at the corner of Western Avenue and Archer Avenue late Friday morning.
Both sets of lights are noticeably brighter, and CDOT officials said the true effect will be clear to drivers and pedestrians at night.
Though the city hasn’t gotten much feedback yet, according to Steele, expectations are that that will change once the lights spread to more areas of the city.
“The feedback we’ve been getting, so far, is, ‘Gee, it sure looks different,’” Steele said.
Along with environmental and financial benefits, city officials said the new lights are designed to cast their glow directly downward, as opposed to the old lights that were well known for their light pollution, otherwise known as “sky glow.”
This downward cast will also decrease what is known as “light trespass” — another feature of the old lights, which caused the glow to seep into homes nearby, city officials said.
Each fixture is estimated to reduce electricity use by around $40 to $70 annually and will have a longer lifespan than the lights they replace.
CDOT plans to continue replacing those lights pending further funding, according to CDOT Commissioner Gabe Klein.