Compact Fluorescent Lamps

Compact fluorescent lamps (CFLs) provide an energy-efficient al­ternative to incandescent lamps. When replacing incandescent light sources, Compact fluorescent lamps can achieve energy savings of up to75 percent. And the life expectancy of a compact fluorescent is about 10 times that of a standard incandescent lamp. In recent years, much progress has been made in adapting Compact fluorescent lamp technology to a growing number of incandescent appli­cations. Hurdles regarding color quality, power quality, light projection and size have been cleared, opening up new avenues for saving energy in applications normally reserved for incandescent lamps.

Compact fluorescent lamp Shapes

One of the primary goals in Compact fluorescent lamp design has been to reduce the overall size of the lamp to fit into conventional incan­descent fixtures. Although the incandescent lamp is still smaller than most Compact fluorescent lamps of equivalent light output, there are a variety of Compact fluorescent lamp shapes that are designed to serve in specific incandescent applications:

Twin-Tube And Multiple-Tube Configurations

One of the earliest Compact fluorescent lamp designs is the "twin-tube" lamp. This lamp essentially consists of two short T4 fluorescent tubes that are connected by a bridge, resembling a type of "U" lamp (with a very tight bend). To develop more compact designs, manufactur­ers also use multiple twin tubes in the same configuration, all connected by bridges to form a single light source. Another version of the twin-tube is the rapid-start T5 twin-tube (or U-tube). These lamps are designed for full-size fluorescent applications and are available in lamp lengths up to 22-1/2 inches. These lamps can be dimmed using compatible electronic ballasts.

Reflector

For downlighting and wall-washing applications, reflectorized Compact fluorescent lamps provide a wide-angle beam of light. Due to the relatively large size of the compact fluorescent source (compared to an incandescent "point" source), it is difficult to produce a well-defined narrow beam using fluorescent technology. However, with improvements in reflector designs, manufacturers are now producing compact fluorescent "R-lamps" that produce candela distributions that are similar to the incandescent R40 flood lamps that they would replace.

Enclosed

Some Compact fluorescent lamps include a globe enclosure that surrounds the light source. Many food service establishments use deco­rative globe-shaped compact fluorescents in pendant lamps mounted above the dining tables. Enclosed compact fluorescents should be consid­ered whenever the lamp is not concealed by the luminaire and dimming is not required.

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