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The installation of 82 luminaires on a new parkway in Fairview, TX, has become what you might call a “legacy project.” Custom LED luminaires designed for this roadway are now part of the standard product line offered by Sarasota, FL-based manufacturer Sunovia Energy Technologies. With the city’s blessing, Sunovia will market the luminaires under the name, “The Fairview Collection.” But that’s not their only legacy. The fixtures are also part of Fairview’s rapidly growing collection of environmental initiatives.
“Fairview has a long history of being a very progressive town; one that spends a lot of time promoting the environment, resource conservation and energy efficiency,” says mayor Sam Israeloff. “We have everything from a tree preservation ordinance to rebates for our residents for installing watersaving appliances or rainwater collection systems. We are one of the few communities that have a green building ordinance that applies not just to commercial properties, but to residential properties.” Storm-warning sirens are solar-charged, and the town is also investigating the use of solar-powered irrigation and vegetation water-filtration systems.
Fairview’s most recent foray into sustainable design is the installation of LED luminaires (30 roadway and 52 walkway) along the ½-mile-long, four-lane Fairview Parkway. The parkway is expected to expand to 3.2 miles as this area grows. The road is bordered by a mixed-use lifestyle center (including retail and condominiums) to the south and residences (mostly condos) to the north. The parkway opened in July and is reportedly the first new street in Texas illuminated using LEDs.
The original system was designed using a 400-W metal halide decorative luminaire, arm and pole. That design called for full-cutoff luminaires with a luminaire efficacy of 54.6 lumens per watt and a target efficacy of 13.7 lumens per watt (Table A). Fairview officials, however, decided to take a second look at the project. “Town leaders were looking for opportunities to save energy using a leading-edge technology, such as solid-state lighting,” says Rick Kauffman, Kauffman Consulting, Atlanta, who designed both the project lighting, as well as the luminaire and LED optical system for Sunovia.
 Fairview’s former economic development coordinator eventually invited Sunovia to make a presentation to town officials. “They brought out samples and demonstrated that LEDs could be used for indoor lighting, outdoor lighting of structures like parking garages, and could also be arranged in banks of LEDs to be used as streetlights,” says town engineer James Chancellor. The company prepared a cost analysis and return-on-investment study comparing the metal halide system to an LED system (Table B). “The report demonstrated a three-year ROI for the additional costs and provided a 12- year parts and labor warranty. Since the LEDs, themselves, are reported to last 12 to 15 years due to their low heat and electricity usage, maintenance costs would be substantially reduced.”
Fairview ultimately approved the redesign with four key objectives in mind: compliance with its dark skies ordinance; energy savings; reduced maintenance; and perhaps most importantly, bolstering the town’s leadership position in using green technology. “Though we might be a town of 9,000, we are growing at a rate of roughly 20 percent per year. And by leading in green technology, we mean leading in a sense of having committees that are focused on environmental issues, not just bringing cable and broadband to your house,” says Matt Donnell, assistant to the Fairview town manager.
HITTING THE ROAD
The 82 luminaires using Cree LEDs are a one-for-one replacement of the previously planned metal halide system. The 30 roadway poles/fixtures are spaced at 180 ft and mounted opposite each other along the parkway (not in the median) at a 30-ft mounting height. Sidewalks are on both sides of the parkway. Here, the 52 poles/fixtures are mounted at 16 ft and are on one side of the walkway only, but not necessarily the same side depending on the sidewalk and obstructions.
Two luminaire sizes were used: 28 in. for the roadway fixtures and 21 in. for the walkway fixtures. The roadway luminaires are 225 watts (vs. 400-W metal halide), while the walkway fixtures are 55 watts (vs. 100-W metal halide). Energy and maintenance savings are projected at $180,000 over a 12- year LED lifespan.
 Cost savings weren’t the only enticement. “HID lighting blasts out a lot of light in all directions. LEDs can be more directed and focused, and thereby we don’t need as much light to light the same target area. With LEDs being a very small point source, we can focus the light exactly where we need it. This allows us to do a better job of optical design and only put light on the target area,” says Kauffman. “By optimizing target utilization of the light, we can also reduce trespass light—light that strays off into people’s bedroom windows at night or causes excess glare for other nighttime activities. We have virtually eliminated this.” According to the Sunovia systems comparison, the LED system will raise target efficacy to 28 lumens per watt vs. 13.7 in the original metal halide scheme.
The directional light provided by LEDs was an important selling point to town officials sensitive about the dark-skies issue. “If you are not actually on the roadway, it’s hard to tell if the lights are even on from a distance. As you approach the roadway, the pavement and sidewalks are illuminated, but the adjacent land and yards are not,” says Chancellor. “Also, there are no bright spots directly under the poles as there are with traditional lighting.”
Color was another issue. “High-pressure sodium has sort of a gold or orange glow to it; it has poor color rendering, whereas LEDs have much higher blue and red content and render colors much more accurately so that people can recognize objects much more easily at lower lighting levels,” says Kauffman.
Even though the road just opened in July, Chancellor reports that word is quickly spreading to other cities in Texas. “Dallas and Plano have asked about our fixtures, and the North Central Texas Council of Governments asked us to give a presentation at one of their green- energy roundtable discussions.”
Another step for Fairview toward securing a green legacy.
October 09
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