Lighting Upgrade - A Perfect Opportunity to Re-evaluate
Strategies should be customized for the type of facility being evaluated for lighting energy savings. Lighting requirements for any space are driven by the type of activity taking place within the space. A lighting energy upgrade project always begins with a thorough evaluation of how the facility is being used by its occupants. These key elements should be considered in all lighting upgrades:
Building use pattern: Studying the building occupancy pattern and its energy use pattern will reveal where best gains can be found. A small reduction in the lighting system wattage in a building that operates 24 hours will result in significant savings and should not be overlooked.
Benchmarking and Retro-commissioning: Since the use of a space continuously evolves over time, a re-evaluation of time delay settings and presets of lighting control devices such as occupancy sensors and daylight sensors within existing spaces would be a good start place to start investigating energy savings.
Measurement of lighting levels: An exercise of reviewing task related areas in an existing space together with taking illuminance measurements in those areas will reveal areas that can benefit from reducing lighting and hence result in overall energy savings.
Lamp wattage: Modifying the quantity and wattage of lamps in lighting fixtures to more efficient lamps may result in a 10 – 25% reduction in energy use.
Reduce system wattage: Selecting the right lamp and ballast combination in fluorescent lighting fixtures will determine the actual wattage used by the lighting system. Ballasts with high ballast factors drive more lumens from the lanp and use more energy. On the other hand, ballasts with lower ballast factors drive relatively lower lumens from the lamp and use less energy. A careful study of the application will help determine which ballast is suitable.
Reduce over-lighting: By reconfiguring a few fixtures and increasing spacing of efficient lighting fixtures and reducing the number of lighting fixtures can also result in additional energy savings.
Lighting controls: Addition of ‘occupancy sensors’ in small enclosed rooms and all back of house areas can increase lighting savings by an additional 10-40%. Additional use of wireless lighting controls to manage lighting in large facilities can also result in significant lighting energy savings.
Utilize daylighting: Where possible use of daylight sensors can provide additional operational lighting energy savings. Although not very easily retrofitted in existing spaces, certain space such as lobbies and atriums with ample daylighting could benefit from fixtures retrofitted with dimming ballasts.
Minimize environmental impact: A lighting upgrade is a good opportunity to look into ways of reducing environmental impacts. Few key elements to consider are use of lamps with low mercury content; participation in lamp recycling programs; utilizing extended life lamps to reduce material; use of well shielded lighting fixtures to reduce light pollution; and use of lighting fixtures with high content of recycled material.