Street lights with controls systems offer dynamic dimming during long periods of inactivity, a feature with tremendous potential to save energy, mitigate waste, reduce light pollution, and increase public safety. In spite of all these advantages, there is no nationwide control standard established to date, and LED street lights are being installed en masse without this important feature. These fixtures are likely to be in use for as long as 20 years, so the fixed-wattage, un-retrofittable fixtures sold today represent a significant loss in long-term savings opportunity.
An integrated, addressable LED street light could offer an additional 40–50% savings beyond what can be expected from the simple upgrade to LEDs, with only a small, highly cost-effective additional expense. Also, including controls on-board offers the potential for establishing a demand response opportunity in the future, an important feature as we progress towards more significant evening energy use peaks.
Controls capability offers larger savings and cost/benefit potential for street lighting than the use of a static LED in isolation, given the marginal efficacy advantages over HPS. A dynamic controls approach for LED street lighting also addresses dark sky issues, reducing light pollution during the long night-time hours of inactivity typical of most residential settings.