City of San Jose Street Lighting Demonstration and Design Criteria

In response to the Climate Action Plan, the City of San Jose is replacing all their LPS street lighting with LED. The largest challenge in replacing the street lighting is the potential sky glow increase for Lick Observatory. Clanton & Associates was hired to evaluate the visibility differences between different white light sources and the existing LPS and the sky glow effects. Clanton & Associates found that visibility increased dramatically with white light. As a result, Clanton & Associates was able to recommend dimming the lights during curfew hours and redirecting all the lighting downward which resulted in no sky glow increase.

Scope of Work Performed

Demonstration projects were conducted in order to inform the City on equipment selection, quality visual results, and to provide input from the community on subjective preference. The demonstration evaluated the existing LPS lighting with HPS, LED, and Induction systems at 100% and 50% lighting levels. Energy efficient, high quality, and low maintenance luminaires were selected for the one for one replacement demonstration. Visibility comparisons were evaluated by a research team from Virginia Tech while Clanton & Associates conducted the subjective evaluations. The results from the demonstration projects were used by Clanton & Associates to create street lighting design criteria for the City.