By Correne Martin
The city of Prairie du Chien has been recouping the cost of the recent conversion to LED lights in the downtown district so rapidly that Alliant Energy has taken notice and sent a letter questioning the recorded reduction in electricity.
“The letter asked us to notify them of the reason for the change in usage,” stated Terry Meyer, co-manager of public works. “Our normal usage for two meters was about 6,400 killowatt hours (kwh) per month, but November’s usage (thanks to the LEDs) was under 2,000 total, between the two meters.”
Indeed, Alliant was correct. The city made the change in October, converting 85 street lights from 150-watt metal halide fixtures to LEDs, on Blackhawk Avenue from Marquette Road to Main Street, and on Main Street from Blackhawk to Iowa Street. Meyer applied for and received a $10,000 clean energy grant from the Wisconsin State Energy Office this fall. That was used toward the expenses of the project, leaving the total out-of-pocket cost for the city at $19,155 out of $29,155. The funds have been secured by 2014-2016 Capital Improvement Plan borrowing.
“The expected payback from energy savings is three years but I think it might be even sooner than that,” Meyer explained.
According to Meyer, the changeover has the potential to save the city about 54,728 kilowatt hours per year, equalling an annual savings of about $7,052. The LEDs have a five-year warranty and a life expectancy of 50,000 hours of on-time use, Meyer added. Estimates are that each light would be on approximately 4,300 hours per year. Considering those numbers, the lights should last about 11 and a half years. In total, the overall cost savings during that time period could be around $78,000. The city has been working with E3 Energy Coalition, of Viroqua, on energy-saving projects like this one. (In 2013, the wastewater facility lighting was upgraded with grant funding.)
The next LED conversion project on the city’s list is to install them on St. Feriole Island and the Highway 18 Bypass.