The Marine Corps Base Quantico (MCBQ) in Virginia replaced nearly 2,000 old and inefficient streetlights, parking lot lights, and exterior area lights across a 1,000-acre site, which includes about 101 parking lots. The MCBQ replaced its mercury vapor and high pressure sodium fixtures with LED fixtures.
The parking lots range in size from 1,781 square feet to 309,218 square feet representing a total area of nearly 4 million square feet of lighted space, enough to park 11,578 cars. Project planners estimate the retrofits will save the Marine Corps 459,346 kWh annually, or more than $32,000 per year in electricity costs. There are also maintenance staff labor savings attributed to fewer lamp replacements.
In one parking lot alone, the base realized an energy savings of 85 percent when the existing mercury vapor fixtures were replaced with LED fixtures. Three 78-Watt LED fixtures provide adequate light for the entire 9,800-sq-foot parking lot.
The Energy Independence and Security Act of 2007 requires the US Department of Defense to reduce building energy consumption by 30 percent by 2015, relative to a 2003 baseline. The outdoor lighting retrofit at MCBQ is one part of the Marine Corps’ efforts to help the military comply with that requirement.
In determining the cost effectiveness of the project, the MCBQ team calculated savings based on a 12-hour operation day and an off-peak electric rate of $0.07/ kWh, according to a case study of the project. Non-energy-related annual cost savings were estimated based on replacing one-third of the lamps per year at an estimated labor cost of $13.75 per lamp. The simple payback calculated by the MCBQ for this project was 18-25 years. If MCBQ undertook this project today, the payback would likely be 5-7 years because LED fixture prices have come down, and due to other factors.