Dynamic Exterior Lighting for Energy and Cost Savings in Department of Defense Installations

Publication Date: 
03/01/2015

Exterior lighting for streets, roadways, parking lots, and other outside sites represents nearly 10% of the electricity consumed on military bases. Lighting in these areas typically consists of high pressure sodium or sometimes metal halide lamps that are normally controlled by photo-sensors located centrally or sometimes on each fixture. This limited functionality includes turning the lights on in the evening and off in the morning regardless of occupancy levels, thereby consuming more electricity than necessary.

The goal of this project was to quantify electricity savings and cost saving, achieved through the use of advanced lighting sources and smart lighting controls. Our approach included improving the quality and quantity of light compared to pre-retrofit conditions by demonstrating advanced light sources (LED luminaires replacing HPS lamps) with three lighting controls systems developed by Philips Lighting. The Dynadimmer, Starsense, and Light-On-Demand (LOD) systems were demonstrated at a parking lot, a major roadway, and a tactical equipment maintenance facility (TEMF), respectively. All demonstrations were completed at Fort Sill.

Overall, this demonstration project has shown that advanced LED light sources with controls can result in substantial energy and cost savings (60 to 90% depending on the application areas and usage patterns) while improving the quality of light in terms of color rendering and brightness, which has been confirmed by user surveys. Life cycle cost analysis has shown that these systems can provide savings to investment ratio (SIR over 20 Yrs.) of more than 2.0 and payback of less than 5 years for Dynadimmer and LOD and less than 8 Yrs. for Starsense in areas where average cost of electricity is $0.10 or more per kWh. Electricity rates vary between $0.044 per kWh to $0.28 per kWh across the USA for industrial customers and are higher for commercial and residential customers. Furthermore the actual rates are determined by negotiations between base administration and the utility companies.