DOE Releases GATEWAY Report on LED Roadway Lighting
July 11, 2012
The U.S. Department of Energy (DOE) has published the first evaluation report from a GATEWAY demonstration on NE Cully Boulevard, a residential collector road in Portland, OR. Six different types of roadway luminaires were installed in side-by-side groupings and evaluated for initial performance: three LED, one induction, one ceramic metal halide, and one baseline high-pressure sodium (HPS). In addition to performance data, the report also includes an evaluation of the economic feasibility of each of the alternative luminaires and documents feedback collected from local Illuminating Engineering Society members who toured the site.
Key findings include:
- Although not all of the installed products performed equally, the alternative luminaires generally offered higher efficacy, more appropriate luminous intensity distributions, and more favorable color quality when compared to the baseline HPS luminaire.
- Some of the alternative luminaires did not provide sufficient illumination to all areas—vehicular drive lanes, bicycle lanes, and sidewalks—or would likely fail to meet design criteria over the life of the installation because of expected depreciation in lumen output.
- Based partly on the cost of the small quantity of luminaires purchased for this demonstration, the shortest calculated payback period among the alternative luminaire types was 17.3 years. At prices that are more typical of larger quantity purchases, however, the payback drops to less than 10 years.
- A networked control system was installed on all demonstration luminaires, and recorded power values were compared to spot measurements and manufacturer reported values. While most power measurements were fairly consistent with their expected values, one LED luminaire was substantially lower. Although a reduction in power is generally favorable, accuracy in reported values is essential, since utilities often base tariffs on rated power.
The report is available for download here. This lighting demonstration is one of many DOE GATEWAY demonstrations that showcase high-performance LED products for general illumination.