Browse Projects > Detailed View

Benefits of Adaptive Roadway Lighting


Traditionally, roadway lighting has consisted of dusk-to-dawn operation, controlled through photocells or timers, producing a static level of illumination throughout the night. Patterns of use of roadways throughout the night are not uniform. To address growing concerns about the costs of roadway lighting as well as the negative environmental consequences (e.g., light pollution), adaptive roadway lighting strategies in which light levels are adjusted during the night to address different levels of use are beginning to emerge. In addition, technological developments (e.g., light-emitting diodes [LEDs]) are occurring that potentially make adaptive roadway lighting easier to accomplish. Research is needed to assist transportation agencies in deciding whether, when, where and how to implement adaptive roadway lighting.


The objective of this research is to provide a basis for rational decisions regarding the use of adaptive roadway lighting.


In the U.S., roadway lighting uses 51 TWh annually (Navigant, 2010 U.S. Lighting Market Characterization, 2012) and street and roadway lighting are among the highest municipal government expenses (Sustainable Pittsburgh, Lighting the Way to a More Sustainable Future, 2012). Governments are under intense pressure to reduce expenses. However, concern about liability and safety may limit governments' willingness to consider reductions in light levels. Research on the safety and visibility effects of lighting is needed. Further, information about the implementation and limitations of adaptive lighting must be gathered and developed.

Related Research:




Among the research tasks needed are:

Assessment of visibility and safety impacts of varying light levels throughout the nighttime.

Development of methods to measure temporal use profiles of nighttime roadway use.

Understanding technological developments that could facilitate adaptive roadway lighting.

Summarizing barriers to adaptive roadway lighting (e.g., initial costs, liability concerns).

Development of tools to assist transportation agencies in identifying economic benefits and costs associated with adaptive roadway lighting.


The research summarized here should be disseminated to groups such as the American Association of State highway and Transportation Officials (AASHTO) developing warrants and guidelines for roadway lighting, and to state and local highways agencies planning lighting systems along highways and streets.

Sponsoring Committee:ACH40, Human Factors of Infrastructure Design and Operations
Date Posted:01/06/2015
Date Modified:01/12/2015
Index Terms:Adaptive control, Lighting, Costs, Highway safety, Night visibility, Environmental impacts, Light emitting diodes, Technological innovations,
Cosponsoring Committees: 
Operations and Traffic Management
Safety and Human Factors

Please click here if you wish to share information or are aware of any research underway that addresses issues in this research needs statement. The information may be helpful to the sponsoring committee in keeping the statement up-to-date.