Description:

This measure involves replacing a facility’s parking area lighting fixtures with more efficient fixtures that will deliver the same illumination at reduced power draw, and reducing the lighting level during unoccupied periods. Parking areas are traditionally lit with high-intensity discharge (HID) lighting fixtures, typically metal halide or high pressure sodium lights. Replacing these fixtures with newer, more efficient technologies such as light-emitting diodes (LED) will yield energy savings.

For office buildings, exterior lighting typically consists of parking area, walkway, and building façade lighting. This lighting is typically turned on at sunset and turned off at sunrise, based on photosensor or astronomical timeclock control. Energy savings can be realized by lowering the exterior lighting level below full load power during times when nobody is present.

Special Considerations

• Overall lighting system efficiency, fixture life, light output depreciation, maintenance, environmental impact, and controllability should all be considered when replacing lighting fixtures.

Estimates for this measure come from the Department of Energy's Advanced Energy Retrofit Guide.