LED, HID, Fluorescent Fixtures Among Exterior Lighting Optionstest

By James Piper, P.E.

April 2016

Managers have a range of options when it comes to light sources. Incandescents, widely used in the past, have been replaced for the most part by longer-lasting and more energy efficient light sources. Halogen lamps are another form of incandescent, but they offer a longer service life. Managers must carefully consider their high operating temperatures.

Fluorescent and compact fluorescent fixtures also are common and are available in a range of shapes, wattages, and color temperatures. Electronic ballasts offer managers the improved overall efficiency of the fixtures and have allowed their use in colder environments.

High-intensity discharge (HID) lamps, including mercury vapor, metal halide, and high-pressure sodium, offer a range of color rendering and decent energy efficiencies.

LEDs are the newest members of the outdoor light sources. LEDs offer good color characteristics, since manufacturers can change the product’s chemical composition to alter the color output as needed. LEDs offer extremely long service lives — often 100,000 hours or more — reducing maintenance costs as the interval between replacement exceeds that for all other widely used light sources.

LEDs are one of the most effective light sources when it comes to placing lumens where they are needed uniformly and with little or no glare. Their small sizes allow fixture installation in applications with tight clearances, and they offer very high energy efficiencies. 

James Piper, P.E., is a national facilities consultant based in Bowie, Md. He has more than 30 years of experience with facilities maintenance and engineering issues.