Willmar to test LED streetlights: Utility refinishes downtown junction boxes
WILLMAR -- Willmar Municipal Utilities will be conducting a year-long test of energy efficient LED streetlights in three residential neighborhoods.
Also, the utility recently refinished the 18 electrical junction boxes found at intersections around downtown and in Old Town.
One LED streetlight will be installed at each of the three locations across the city. The locations represent different types of neighborhoods and are home to a utility employee, a City Council member and a Kandiyohi County employee. All have agreed to monitor the effectiveness of the lights for up to a year.
LED stands for light-emitting diode. Willmar Utilities purchased three Philips LED streetlight units for the test period. The first LED unit was installed Thursday afternoon in front of the county employee's residence in the 400 block of 23rd Street Southeast, said Jeff Kimpling, manager of electric services.
During the past three years, the utility has been researching the possibility of gradually replacing the high-pressure sodium bulbs currently in use with LED units in the city's 3,165 streetlights.
The utility began using high-pressure sodium bulbs in the early to mid-1970s as replacements for mercury vapor lights.
The utility decided to buy three LEDs based on favorable results of a recent one-week demonstration project in which one LED was installed in the 1100 block of 14th Street Southwest and another was installed in the 1000 block of 19th Avenue Southwest.
The long-range goal with LEDs is to save energy. The utility compared the amount of energy used by a high-pressure sodium unit and an LED unit and found the LED used about half as much energy as the high-pressure sodium light.
Kimpling said the energy usage is similar to the LEDs used in city traffic signals for the past five to six years.
The utility will also consider other factors before switching to LEDs. One is cost. During the past two years, LED prices have fallen from the $700 to $800 range to the $400 to $500 range. The three LED units just purchased cost $427 each.
Other factors are maintenance and quality. A high-pressure sodium head is warranted for 3 or 5 years. The LED warranty has increased to 3 or 4 years.
Research indicates a high-pressure sodium bulb will last an average of 13,000 hours (about 3 to 5 years) while an LED bulb is predicted to last from 50,000 to 75,000 hours (about 11 to 17 years).
However, the amount of light produced by an LED bulb can gradually decrease after 3 to 4 years (depending on the quality), whereas a high-pressure sodium bulb stops emitting light when it burns out.
High-pressure sodium units can be disassembled at the shop, parts can be replaced and the unit returned to service. However, the utility must pay recycling costs for disposing of the various parts of a high-pressure sodium unit.
An LED unit is self-contained. If the unit quits working, it is shipped back to the factory.
"We know what we have out there with our high-pressure sodiums. We know how they act, we know how long the bulbs and heads will last. The LED technology is a very rapidly advancing field. The costs are starting to come down,'' said Kimpling.
"We've seen all kinds of test results on what they do, the amount of energy they use. We've seen a lot of positive things, but we've seen some negative things,'' he said. "We're optimistic in the next few years that we're going to see something out there that we're satisfied with and there will be more of them.''
The utility recently completed refinishing its 18 electrical junction boxes located at intersections downtown and in Old Town. The worn out redwood tops were replaced with redwood-colored composite lumber and the steel cases were sandblasted and painted a dark green.
The utility consulted with Beverly Dougherty, project coordinator for the Willmar Design Center, and Bruce Peterson, city planning and development director, on the colors of the wood and paint. Kimpling said Dougherty and Peterson selected the colors.
"It didn't matter to us,'' said Kimpling.
Dougherty said the refinishing project is a great downtown improvement.
The junction boxes were installed during the 1982 downtown redevelopment project and are a function of the underground electrical system. The boxes can be tipped up to allow linemen to unplug high-voltage lines and work on underground transformers.
The boxes were originally designed with redwood tops for seating. Over the years, utility employees removed and refinished the redwood tops two or three times. The tops had previously been painted green by a service club without the knowledge of the utility or the Design Center, according to sources.
The utility decided to proceed with the latest project because the tops were worn out.
Perkins Lumber of Willmar fabricated the tops, B and L Utility Maintenance of Annandale sandblasted and repainted the boxes, and utility line superintendent Rich Maxfield and his crew removed the old tops and installed the new tops. The entire project came in under $10,000.
"We're happy with the way they turned out and we've had a few positive comments from downtown owners,'' said Kimpling. "We hope last as long as the redwood.''