The Siemens Energy Analysis Team has surveyed the outdoor lighting systems on the Fairfax, Arlington and Prince William Campuses. The lighting systems surveyed include road way, parking lot, walkway and parking garage lighting systems. GMU has requested that the Arlington Campus not be included in the project due to the ongoing construction that might affect the lighting. It is recommended that the high intensity discharge (HID) lighting in the parking garages included in the survey be replaced with high output T5 fluorescent fixtures. It is recommended that the road way, walkway and parking lot lighting be converted from the high pressure sodium HID fixtures to light emitting diode (LED) based fixtures. The LED fixtures provide greatly reduced wattage and lamp life while providing greatly improved color rendering and visual acuity for security. It is anticipated that the increased lamp life of the LED fixtures will provide a reduction in the required maintenance and replacement materials for the HPS fixtures. The maintenance savings reported assume that the labor used to conduct the lighting maintenance can be redirected to other maintenance activities. The overall energy and cost savings resulting from the upgrades are listed below:
Estimated Electrical Energy Savings = 1,951,450 kWh/yr (6,660 MMBtu/yr)
Estimated Energy Cost Savings = $92,541 /yr
Estimated Maintenance Cost Savings = $42,360 /yr
Estimated Implementation Cost = $3,702,797
Simple Payback Period = 27.4 years
While the simple payback for the LED lighting is longer than other lighting projects, the choice of this advanced technology provides GMU with a highly efficient outdoor lighting fixture standard that moves the University toward the long term sustainability goals. The LED lighting provides a “white light” that greatly improves the color rendering and provides the visual appearance of brighter lighting for the outdoor areas.
The proposed lighting system upgrades were identified through detailed surveys of the existing systems. The SBT Energy Analysis Team installed “mock-up” fixtures in multiple locations which gave GMU ample opportunity to ensure that the lighting system replacements will meet with University standards for outdoor lighting in all applications. Siemens requested that GMU examine the system “mock-ups” and provide approval that the recommended systems will meet University standards for lighting in the areas affected. Siemens received approval for the lighting system replacements from GMU based on the example fixtures installed. Detailed discussion of the recommendations and the associated savings is given in the Engineering Calculations section.