IP, Reports & Roadmaps | Jun 16, 2014

Lighting Research Center Authors National Academies Report on New Roadway Lighting Technologies

The rapid development of lighting technologies, particularly solid-state systems using light emitting diodes (LEDs), has opened a universe of new possibilities as well as new questions about roadway lighting in the U.S., which for decades has been dominated by the use of high pressure sodium (HPS) lamps. Other light source technologies have also been angling for roadway market share. There is a critical need for objective technical information about new types of roadway lighting among transportation agencies. In response, the Transportation Research Board (TRB), part of the National Academies, initiated a project to evaluate new lighting technologies and identify new metrics for comparison. Lighting Research Center (LRC) scientists John Bullough, who served as principal investigator, and Leora Radetsky co-authored the report, entitled "Analysis of New Highway Lighting Technologies." The LRC is part of Rensselaer Polytechnic Institute, the nation’s oldest technological research university.

 

A major challenge in assessing new roadway lighting technologies is that information for different systems is given in different forms, making comparisons difficult. Bullough and Radetsky systematically analyzed the performance of a number of representative luminaires of each type, and developed a consistent "data sheet" format, allowing direct comparisons. They found that many commercially available LED, ceramic metal halide, and plasma discharge roadway lighting systems can meet existing standards for lighting collector roads and freeways, achieving comparable or greater pole spacing than HPS systems and in many cases, resulting in lower energy use.
Importantly, say Bullough and Radetsky, not all systems of each type performed equally well. This underscores the importance of developing consistent data reporting formats such as those in their report.
The authors found that pole height was an important factor in the overall effectiveness of the roadway lighting system. A metric developed by the LRC, called luminaire system application efficacy (LSAE), can be used to optimize pole height and spacing to achieve optimal economic performance of different roadway lighting designs. Bullough and Radetsky also recommend that transportation agencies begin considering new benefit metrics for roadway lighting including photometric quantities based on mesopic vision, brightness perception and visual comfort.
According to Bullough, "Technologies such as LEDs are becoming mainstream choices for roadway lighting. The findings in our report can help agencies make better decisions as they face these choices."

The report by Bullough and Radetsky can be downloaded from the TRB website at:
http://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP20-07(305)_FR.pdf.
FEATURED

Lumileds RGBW Module Achieves Breakthrough Flux and Color Control

Lumileds RGBW Module Achieves Breakthrough Flux and Color Control Lumileds, a global leader in innovative lighting solutions, today introduced the Luxeon MultiColor Module 2.5 W, a compact RGBW module that produces leading flux and achieves exact color points in architectural and general outdoor lighting applications. The 4-in-1 module simplifies system design by ... Read more »

FEATURED

American Bright introduces Smart RGB Addressable Rope Light Solutions

American Bright introduces Smart RGB Addressable Rope Light Solutions American Bright brings to the market their smart RGB+IC LED flexible rope lighting solutions allowing for boundless application opportunities. The smart LED light source includes the controller and RGB chip in one package allowing for each LED to be addressable. Additional adaptability is gained ... Read more »

FEATURED

Goniometer LGS 650: Higher Accuracy and Reproducibility

Goniometer LGS 650: Higher Accuracy and Reproducibility Goniophotometry is an absolute measuring procedure that can achieve a higher level of accuracy than sphere photometry. It does not require a luminous flux standard, but in contrast is often used for calibrating standard lamps for luminous flux. In addition to the luminous flux, photometric spatial ... Read more »

FEATURED

Cree® XLamp® High Current LED

Cree® XLamp® High Current LED The XLamp High Current LED Array family is optimized for best-in-class lumen output, efficacy and reliability at high drive currents. XLamp CMA LEDs share the same package design and LES sizes as Cree's industry-leading CXA2 Standard Density LEDs, enabling lighting manufacturers to address a range ... Read more »

EDITORIAL

High Conductive Foils Enabling Large Area Lighting

High Conductive Foils Enabling Large Area Lighting Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP as one of the leading partners for research and development for surface technologies and organic electronics and Sefar AG, a leading manufacturer of precision fabrics from monofilaments, developed a roll-to-roll ... Read more »

page_peel