Exterior Lighting Upgrades Deliver Efficiency, Savingstest

By James Piper, P.E.

April 2016

Lighting systems have long been a target for maintenance and engineering managers seeking to reduce the energy use in their institutional and commercial facilities. Lighting systems tend to be low-hanging fruit when it comes to energy-saving opportunities. New lighting technologies and fixture designs, as well as improved control systems, have combined to provide relatively quick paybacks while allowing managers to improve the quality of lighting.

But managers also have opportunities to improve the quality of lighting and reduce energy use and maintenance costs outside of facilities. Lighting systems for parking lots, walkways, signage, and façades all offer potential savings for managers who are willing to invest time and effort. Most exterior lighting systems in use today are more than 20 years old. Technology changes and improvements in light-source efficiencies offer managers the potential for reducing energy use and maintenance costs by 40 percent or more.

With such potential savings, the first impulse is to rush into a lighting retrofit program that simply replaces existing lamps and ballasts or the entire fixture with new, higher-efficiency products. While a one-for-one replacement program is quick and easy, it might not offer the best return, and it might not solve existing lighting issues. One-for-one replacement assumes an existing system is the ideal system for its application and that managers only need to upgrade fixture efficiencies.

If managers are to maximize an upgrade to an exterior lighting system, they must consider such issues as light distribution, glare control, color rendering, and time of operation. Lighting system upgrades need plans, and a plan starts with an audit of existing systems and issues.