| December 5, 2007
- The City of Knoxville plans to invest $781,500 of an $8 million
surplus in energy efficient LED lights to replace the remaining incandescent
bulbs in the city's traffic signals.
That move is expected to save the city more than $220,000 annually
in energy costs and replacement expenditures - meaning the investment
will be paid off in less than four years.
Because the LED lights last five to ten times longer than conventional
incandescent bulbs the total savings are expected to easily exceed
more than $1 million over the life of the new signals.
"We had planned to phase-in LED lights over the next several
years, but when we started looking at the numbers, we realized there
was a significant opportunity to realize a tremendous savings by
getting them all done at once," said Mayor Bill Haslam.
The city has been involved in an ongoing program to gradually
replace incandescent bulbs in traffic lights with LED signals. About
20 percent of them have been replaced over the past few years.
But the one-time, $781,500 investment will allow Knoxville to
complete the program within a relatively short period of time -
and realize the accompanying savings.
LED signals cost more than traditional incandescent bulbs but
they consume just 10 percent of the electricity and last several
A typical LED traffic signal, for example, has a lifespan of 5-10
years whereas a typical incandescent bulb has to be replaced at
least once a year.
Replacing the incandescent lights with LED signals will also allow
the city's Traffic Engineering Department to reallocate staff time
- that had been devoted to the annual light changes - to meeting
other needs in the city.
"We're looking forward to completing this job," said
Steve King, director of the city's Public Works Department. "Reducing
the amount of time staff spends changing light bulbs will allow
us to concentrate on preventative maintenance in other areas."
The project is the first major implementation initiative associated
with the City's Energy & Sustainability Initiative, which was
kicked off last August.
As part of the initiative a 15-member Energy & Sustainability
Task Force - including members from the City of Knoxville, Knox
County, TVA and Oak Ridge National Laboratory, Knoxville Utilities
Board and environmental groups among others - has been charged with
developing a strategic plan for reducing energy consumption and
enhancing the City's overall environmental sustainability.
Madeleine Weil, deputy director of Policy & Communications
and chair of the task force, indicated that the LED replacement
program is a great first step in achieving the group's goals.
"In addition to saving the city money, the LED traffic signals
will reduce environmental impacts associated with the city's energy
consumption," Weil said.
The city anticipates that the LED signals will conserve 3.8 million
kilowatt-hours of electricity, or roughly the amount that 316 average
households would use in one year. That will reduce city government's
annual carbon dioxide emissions by approximately 2,625 tons, or
3.5 percent annually.
The Energy & Sustainability Task Force will meet on December
12th to discuss findings of the city's new Energy & Emissions
More information about the initiative is available at http://www.cityofknoxville.org/policy/energy/