Golden Valley, a western suburb of Minneapolis that is home to a number of corporate headquarters, is crisscrossed with city, state and county roads. As a consequence, the city is responsible for maintaining and paying electricity bills for numerous traffic signals. When the Energy Efficiency and Conservation Block Grant Funding became available as a part of the federal American Recovery and Reinvestment Act in 2009, it seemed like a great opportunity to convert the incandescent signal lights to LEDs.
Traffic Signal Retrofits
LED traffic signals have several benefits– they use up to 80% less energy than incandescent lights, last 6-8 times longer, and require significantly less maintenance. At the time the grant became available, Hennepin County, which maintains signals on county roads, was in the process of replacing its traffic lights with LEDs. Golden Valley had already retrofitted its city-owned signals, leaving just the state-owned signals – for which the city provides maintenance and pays energy bills – to be upgraded.
According to Mitch Hoeft, the engineer who managed the project, the grant was beneficial in driving action to retrofit the signals on state-owned roads. “We [had] started with the publicly owned intersections, where the bulbs needed to be replaced anyway. LEDs made a lot of sense for this application, and the grant gave us an extra push to replace [the state-owned] signals in the city. It was good timing,” he said.
Since Golden Valley’s electric utility, Xcel Energy, offered rebates for converting signals to LED technology, the city was able to secure $8,859 in additional funding for the project. Rebates for yellow signals were not available (since they’re on so infrequently), but the city replaced these anyways to gain the benefit of low maintenance.
Initially, staff were wary of the new lights. LEDs produce less heat than incandescent bulbs, so there was a concern that the signals would be covered with ice and snow in the winter. This skepticism was alleviated after the first winter, in which there were no reported problems with the weather. In fact, residents appreciated the LEDs, since the signals themselves are made up of several tiny bulbs, and therefore create a brighter and more visible light in inclement weather.
To verify the project’s outcomes, Hoeft and other staff tracked the energy use at each intersection beginning in December of 2010. The initial cost savings that they’ve seen have been impressive, adding up to $970 per month and $11,640 per year. “We’ve seen electrical cost reductions of 50%-80% since installing the LEDs,” he noted.
Hoeft also sees the project as a way to reduce the burden on taxpayers: “Operating costs are paid from the tax base in the city, so we’re looking for any ways we can reduce those costs.” With new signals that are energy efficient, cost-effective, and more visible in inclement weather, the benefits of this project abound.
Building Lighting Retrofits
Besides the city’s traffic signals, city staff identified another area in which the city could save energy: its public buildings. Prior to applying for the EECBG grant, the city had worked with the Center for Energy and Environment (CEE) to perform energy audits in city-owned buildings. The audit process, along with data from B3 Benchmarking, a software program for monitoring energy use in public buildings, revealed that the city could significantly save energy and reduce costs by upgrading the T12 (12/8 inch tube) fluorescent lighting in the city’s maintenance buildings to T8 (1 inch tube) systems.
Wanting to extend the benefits of the project to community members, the city hired two local contractors, Gopher Electric and Killmer Electric, to complete the labor for the retrofits. “At a time when construction was hurting,” Hoeft said, “it was good to provide that financial support to put people to work.” Additionally, all of the project supplies were made in the United States – a requirement of the EECBG funding.
In total, the contractors retrofitted 55 fixtures in the city’s vehicle, park and golf maintenance buildings, and 85% of project costs were paid for by the EECBG funding. To secure additional funding, CEE helped the city to apply for utility rebates, which covered the remaining costs. Since the golf maintenance building wasn’t eligible for EECBG funding, the city paid for that project from its own budget.
While the city has funding for building maintenance and improvements, the EECBG grant and utility rebates provided a significant help. “The projects are a no brainer,” explained Park Maintenance Supervisor Al Lundstrom, “but it’s a matter of finding the money in these tight budgets.”
Reviews from staff who work in the retrofitted buildings have been positive. “This project is the best thing we ever did!” claims Todd Fadden, who performs vehicle maintenance for the city. “Not only did it provide better lighting quality for our work, it also doesn’t sound like a swarm of bees in here anymore” (the older T12 lighting produced a distinct humming sound). With new lighting in its buildings and on its streets, Golden Valley is well on its way towards city-wide energy efficiency.
For more information, contact Mitch Hoeft, Engineer at the City of Golden Valley, 763-593-3961, mhoeft@goldenvalleymn.org.
Project Profile
Location: City of Golden Valley, Hennepin County
Types of technology: LED Traffic Signals; Lighting
Description of the project: Retrofitted 14 traffic signals to LEDs and upgraded fluorescent lighting in several maintenance buildings.
Savings: _Traffic Signals_—126,600 kWh per year; $11,640 per year; _Building Retrofits_—13,800 kWh per year; $400 per year
Project Funding: Energy Efficiency Conservation Block Grant ($53,252); Utility Rebates ($8,859).
About the Local Government Energy Action Series:
This effort tells the stories of Minnesota municipalities, counties, and schools and the tangible results of their energy-saving efforts to inspire others to take their own actions.
