Affordable Dimming for CFLs

Fluorescent lighting was introduced in the 1920s as a more energy-efficient alternative to incandescent lighting. Over the past two decades, technology improvements have gradually increased the acceptability of fluorescent lamps for many more applications. Light quality was dramatically improved with triphosphor coatings, fluorescent tubes were folded and shrunk to produce compact fluorescent lamps, and electronic ballasts greatly reduced the start-up flicker and hum. Now additional technological advances—and an unusual court verdict—are moving towards solving one more obstacle to greater use of fluorescent lamps—inexpensive dimmability.

Dimmable ballasts are available today for some standard and compact fluorescent lamps, but they are quite expensive ($60 to $80 per fixture) and require custom dimming controls. (There are presently as many as nine incompatible dimming control systems for fluorescent lamps on the market.) Most also require low-voltage control wires—in addition to the regular electrical wires—connecting the switch box and fixture.