High-ceiling applications such as warehouses, big-box retail spaces and gymnasiums are often referred to as "high-bay" spaces. Commonly, these spaces are lit with high-intensity discharge (HID) light sources, including metal halide and high-pressure sodium lamps. We have seen improvement in both high-intensity fluorescent (HIF) and HID technologies. That said, HIF technology has grown to be a more popular choice as it offers slightly better performance.
Fluorescent lighting has become quite advanced, and with it, a growing number of HIF fixtures have come to market. These superior HIF lighting systems are better for the environment than their HID counterparts and feature:
fast startup and restrike
low lumen depreciation curve
improved dimming options
better color rendering
Choosing the right lighting technology
Fluorescent lamps. Known for emitting uniform, diffuse light along varying lengths, fluorescent fixtures have been the standard for lighting workspaces with relatively low ceilings. Today's high-intensity fluorescent lamps paired with optimized reflecting fixtures have extended the fluorescent light's utility to high indoor ceilings – those above 20 feet. They make a compelling alternative to HID lamps and most rapid-start models now can start at temperatures as low as 0°F.
HID lamps. Unlike the broad coverage of a fluorescent lamp, HID lighting produces intense light on a small area. Therefore, they are often paired with parabolic reflector fixtures.
You can choose from many different types of HID lamps. Metal halide and high-pressure sodium remain most popular for indoor spaces. The main distinction between these two is the type of vaporized metal used for the gas inside the inner glass chamber of the lamp. The more versatile of the two is metal halide. This technology offers a high-quality light, a more efficient lamp/ballast system and plenty of size options. Ballasts for metal halide lamps will start at extremely low temperatures – all the way down to minus 40 degrees Fahrenheit (F).
Metal halide performance has improved with recent advancements. Pulse-start metal halide lamps that incorporate ceramic tubes with electronic ballasts provide outstanding results in situations where color quality, fixture appearance and uniform uplighting are desired, particularly in facilities exposed to high and/or low temperature extremes.
HID installations typically call for fewer fixtures, offering great cost advantages over older types of installations. These lamps perform exceptionally well where distant fixtures must provide light over great distances, such as street lighting, indoor and outdoor athletic facilities and any large space with high ceilings.
Induction lighting and electrodeless lamps. Inductive fluorescents provide exceptional long life and coldstart performance (up to 100,000 hours at –40°F). They can also instantly restrike. However, their efficacy falls short of metal halide and conventional fluorescent lamps. They also have high lumen depreciation (about 40 percent). Further, these lamps produce light utilizing radio frequency energy rather than an electric arc, so in certain applications, they could negatively affect nearby electrical equipment.