Extended Runtime at Signalized Intersection Using Backup Power after the Loss of Utility Power

Lessons learned after hurricanes revealed that although most traffic signal infrastructure withstood the impacts of the storms, signalized intersections were not operational due to lack of utility power. Current traffic cabinets employ a standard uninterrupted power supply (UPS) system, which is powered by lead acid batteries, an outdated technology that provides power for only up to 8 h of operation. For this study, a liquid propane generator was tested successfully to provide constant power without issues. A system that included a battery + solar backup was tested successfully to provide power for several days without issues. This system is not usually an issue after hurricanes, especially if adequate solar energy generation is provided to charge the battery during available daytime hours. The result of the testing provides options for transportation agencies for extended runtime at signalized intersections using backup power after the loss of utility power.