The U.S. Department of Energy’s (DOE) Municipal Solid-State Street Lighting Consortium published guidelines for converting to LED roadway lighting. “The Model Specification for LED Roadway Luminaires” is for cities, utilities and other local agencies interested in saving energy by switching from traditional lighting technologies to solid-state lighting (SSL), which uses light-emitting diodes (LEDs) instead of filaments or gases.
The estimated 35 million streetlights in the United States consume as much electricity each year as 3.9 million households. Streetlighting ranks among the biggest fixed costs for cities.
“Converting our nation’s streetlights to LED technology could make a substantial dent in our energy consumption while also improving quality of illumination but only if the right choices are made,” said Edward Smalley, consortium director of Seattle City Light, a public utility providing electrical power to Seattle and parts of its metropolitan area. “The new specification will help cities, utilities and others make better choices.”
Available online at www.ssl.energy.gov/specification.html, the model specification is designed specifically for LED lighting products, which have the added benefit of reducing maintenance costs, while improving visibility and customer service. The flexible format allows guideline users to modify default values to fit their local design criteria, which can vary from city to city and even from application to application within a given city.
The new specification will help guide the industry and provide a common basis for manufacturers to design products that meet their customers’ needs. As a result, it may prompt more work for installers.
DOE created the consortium last year to inform and harmonize the efforts of the many cities that are pursuing evaluations of LED streetlighting products, often spurred on by block grants and energy mandates. The model specification was developed by consortium members, with feedback from a manufacturers’ working group that included Acuity Brands, BetaLED/Ruud Lighting, Cooper Lighting, GE Lighting Solutions, Hubbell Lighting, LED Roadway Lighting, Leotek, Lighting Science Group, Osram Sylvania, Philips Roadway Lighting, and Philips Lumileds. Their input helps ensure that RFPs based on the specification will result in submissions from multiple manufacturers.
The specification is available with two user-selectable options to accommodate the different preferences commonly found between municipalities and utilities. The system specification option is designed to maximize application efficiency and characterizes luminaire performance by incorporating site characteristics, such as mounting height, pole spacing and number of lanes. The material specification option emphasizes luminaire efficiency, which characterizes luminaire performance without consideration of site characteristics.
A “living document” will be adapted as needed. The model specification will be followed by a supplemental design guide and is expected to have a wide national impact for end-users looking for best practices in specifying LED streetlights.
Stay tuned for a feature on LED streetlight retrofits in the February 2012 issue of Electrical Contractor.