Fluorescent Lamps

Until recently, fluorescent lighting had limited use in most homes; the older fixtures were large, and the light quality was poor for most residential needs. Today, however, new types of fluorescent lighting can provide the comfort and aesthetics traditionally associated with incandescent lighting, and a new generation of compact fluorescent lamps and fixtures is available.

Fluorescent sources can now be considered for almost any area of the home and can be an economical choice over the long term. Although fluorescent tubes may come at a higher purchase price, they use 60 to 80 percent less energy and last 10 to 20 times longer than incandescent bulbs. That translates into significant energy-cost savings and lower lamp replacement costs. Consider these additional benefits:

• Modern fluorescent lamps can have a high colour rendering index (CRI), which means they show colours well.
• Lamp brightness and glare are relatively low and cause little discomfort.
• The new electronic ballasts function quietly and don't flicker like older fluorescent magnetic ballasts.
• Fluorescents work with conventional light switches (however, some may require special dimmer switches).

Fluorescent lamps come in many forms, including compact, linear, circular and U shaped, as discussed in the following pages.

Fluorescent lamps come in many forms, such as U-shaped, compact or circular.

Compact Fluorescent Lamps

Compact fluorescent lamps (CFLs) can now be used in many standard light sockets and fixtures. CFLs typically consume about 67 to 75 percent less energy than incan-descent bulbs and last up to 10 times longer. This makes them ideal for use in fixtures that are not easily accessible, such as recessed luminaires and lights in stairwells. To gain the maximum economic benefits from compact fluorescent lamps, install them in fixtures that are used for three or more hours each day.

If a CFL is too long for the harp (metal shade holder) of a table or floor lamp, you can purchase harp extenders. However, if the harp is too narrow, you may have to purchase a new harp at your local hardware or lighting store. Socket extenders are also available if the socket is too shallow for the CFL base.

Harp extenders are available for table and floor lamps if the CFL is too long or wide.

Wall, ceiling and porch fixtures specifically designed to use CFLs are now available. There are also “dedicated” table and floor lamps on the market. These fixtures are “hard-wired,” which means that the fluorescent ballast is built into the fixture and only a pin-based replacement CFL can be used. This is important for two reasons: it ensures optimal placement of the CFL for light output, and it prevents replacement of the CFL with an incandescent lamp (which would result in lost energy savings).

Pin-based replacement CFL.

CFLs should not be used in closed fixtures indoors (such as globes) because the ballast may overheat.

While it is often not possible to select lamp orientation, compact fluorescents work most efficiently when the lamp is oriented downwards, with the base up. This is because the efficiency of the bulb depends on the temperature of the coldest part of the lamp, which is the end furthest away from the ballast. Since heat rises, a base-up lamp will be coolest at the bottom, producing the greatest amount of light. Keep the lamp orientation in mind when comparing light output, which is rated for base-up operation.

Compact fluorescent lamps work best when the lamp points downwards and the base is up (as shown on left).

In the past, electronically ballasted CFLs sometimes interfered with household equipment using infrared signals, such as television remote controls. Newer remote controls have filters that prevent this problem. If you encounter interference, try moving the CFL away from the television set or placing tape over the small, red rectangular receiver cover on the television.

Until recently, screw-in CFLs were not compatible with conventional household dimmer switches. Using them on dimmer circuits created a fire hazard. However, new screw-in products have been introduced that can be used with dimmer switches, allowing for even more energy savings. To prevent any hazard, it is best to check the package for compatibility with dimmers or for a safety warning.

CFL fixtures can be purchased in single-, double- or triple-tube varieties. In some models, the tubes show, while in others they are enclosed by the manufacturer in a capsule or globe.

Some manufacturers enclose compact fluorescents in a capsule or globe.

The lamps are operated with electronic or magnetic ballasts. Magnetic (or core-coil) ballasts were used with the first CFLs and were usually separate from the lamp. This has the advantage of allowing lamp replacement several times during the ballast lifetime (assuming the lamps continue to be available). Electronic (or high-frequency) ballasts are a more recent development and are usually integrated with the lamp in a one-piece unit. Compact fluorescents with magnetic ballasts are heavier (which can make floor lamps less stable), “blink” when they start, and can produce a faint hum. In contrast, electronic ballasts are lighter, start instantly (although they take up to a minute to reach full brightness), and do not hum.

Compact fluorescents use tri-colour “rare-earth” phosphor coatings inside the tubes to give warm, natural light. These phosphors make the lamps more energy-efficient than lamps with conventional phosphor coatings.

Linear Fluorescent Fixtures

When selecting a fluorescent fixture for a kitchen, bathroom, utility or other area, consider purchasing a linear (long straight tube) fluorescent. There are a number of styles and lengths available, with electronic ballasts for installation on ceilings, under cabinets, over shelves, and in long-armed desk lamps. Many of the lamps sold today give good colour rendition.When installed, these fixtures should be metallic, grounded and shielded to prevent electromagnetic interference with other household equipment.

Linear Fluorescent Lamp

Circular and U-Shaped Fluorescents

Circular and U-shaped fluorescent lamps with electronic ballasts can provide similar efficiency to CFLs when used in table or floor lamps or in overhead fixtures in small rooms. “2-D” lamps, which consist of two D-shaped tubes joined together, are also good choices for these fixtures. Ceiling fixtures equipped with circular lamps are available for household use, and with electronic ballasts, they provide an efficient alternative to linear fluorescents for smaller rooms.

Fluorescent lamps (circular, 2-D)

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