led light: Traffic lights all new
City’s signals now cheaper, last longer, and they’re ‘pretty’
By Trevor Hughes
The Daily Times-Call
LONGMONT — The city’s traffic lights now have more in common with camping headlamps and bike lights than the bulbs in most people’s homes.
City workers earlier this year finished replacing each traffic light in Longmont with LED-based lights. The new lamps are a series of small lights, rather than a single large bulb. Depending on the manufacturer, they sometimes look very similar to the old bulbs.
But that’s where the similarity ends: The LED bulbs are cheaper to operate, last a lot longer than standard incandescent bulbs and are much brighter, said Debi Sadar, the city worker responsible for their installation and maintenance.
“And they’re pretty,” she added.
Sadar, the city’s senior traffic signal technician, was instrumental in persuading her bosses to begin investigating the LED-based lights in 2001.
LED — short for “light-emitting diode” — technology has become widely popular in the past few years. Automakers use them in brake lights, and they’ve become de rigeur in camping flashlights and headlamps.
LEDs work differently than regular bulbs, converting electricity more directly into light. Incandescent bulbs use electricity to heat a metal filament, which then gives off illumination.
The difference means LEDs are dramatically more efficient than incandescent bulbs. Sadar said a typical intersection using regular traffic lights consumes about $925 worth of electricity annually. An intersection equipped with LED lights uses just $110 worth of power.
Multiply those savings by the city’s 75 or so intersections, and the effect on the bottom line is substantial, in the neighborhood of $61,000 annually, Sadar said.
“I don’t think it was so hard once they realized the energy savings,” Sadar said of persuading her supervisors to adopt the technology.
The drawback is the initial cost of the lamps: about $60 for a red LED light, compared to about $3 for a replacement bulb, Sadar said. The LEDs have five-year warranties and usually last for 10 years. Normal bulbs often had to be replaced several times annually, especially during windy years.
The low power needs of the LEDs also opens up the possibility of connecting them to backup batteries at major intersections. The old incandescent bulbs used too much power to make battery backups reasonable, city traffic engineer Joe Olson said.
Olson and other city workers met last week to begin investigating the backup systems.
“Having the LEDs makes it more practical to do that because they don’t draw nearly as much energy,” Olson said.
Now, with all the intersections switched over, Sadar and colleague Derald Johnson keep an eye on lights that have lost some of their LEDs.
This week, they took about 10 minutes to replace a red light that had lost some of its LED pixels. The removed light still was under warranty, so Sadar planned to send it back to the manufacturer.
“They aren’t going out as often, and they’re a lot brighter,” she said.
Trevor Hughes can be reached at 303-684-5220, or by e-mail at thughes@times-call.com.
City’s signals now cheaper, last longer, and they’re ‘pretty’
By Trevor Hughes
The Daily Times-Call
LONGMONT — The city’s traffic lights now have more in common with camping headlamps and bike lights than the bulbs in most people’s homes.
City workers earlier this year finished replacing each traffic light in Longmont with LED-based lights. The new lamps are a series of small lights, rather than a single large bulb. Depending on the manufacturer, they sometimes look very similar to the old bulbs.
But that’s where the similarity ends: The LED bulbs are cheaper to operate, last a lot longer than standard incandescent bulbs and are much brighter, said Debi Sadar, the city worker responsible for their installation and maintenance.
“And they’re pretty,” she added.
Sadar, the city’s senior traffic signal technician, was instrumental in persuading her bosses to begin investigating the LED-based lights in 2001.
LED — short for “light-emitting diode” — technology has become widely popular in the past few years. Automakers use them in brake lights, and they’ve become de rigeur in camping flashlights and headlamps.
LEDs work differently than regular bulbs, converting electricity more directly into light. Incandescent bulbs use electricity to heat a metal filament, which then gives off illumination.
The difference means LEDs are dramatically more efficient than incandescent bulbs. Sadar said a typical intersection using regular traffic lights consumes about $925 worth of electricity annually. An intersection equipped with LED lights uses just $110 worth of power.
Multiply those savings by the city’s 75 or so intersections, and the effect on the bottom line is substantial, in the neighborhood of $61,000 annually, Sadar said.
“I don’t think it was so hard once they realized the energy savings,” Sadar said of persuading her supervisors to adopt the technology.
The drawback is the initial cost of the lamps: about $60 for a red LED light, compared to about $3 for a replacement bulb, Sadar said. The LEDs have five-year warranties and usually last for 10 years. Normal bulbs often had to be replaced several times annually, especially during windy years.
The low power needs of the LEDs also opens up the possibility of connecting them to backup batteries at major intersections. The old incandescent bulbs used too much power to make battery backups reasonable, city traffic engineer Joe Olson said.
Olson and other city workers met last week to begin investigating the backup systems.
“Having the LEDs makes it more practical to do that because they don’t draw nearly as much energy,” Olson said.
Now, with all the intersections switched over, Sadar and colleague Derald Johnson keep an eye on lights that have lost some of their LEDs.
This week, they took about 10 minutes to replace a red light that had lost some of its LED pixels. The removed light still was under warranty, so Sadar planned to send it back to the manufacturer.
“They aren’t going out as often, and they’re a lot brighter,” she said.
Trevor Hughes can be reached at 303-684-5220, or by e-mail at thughes@times-call.com.
