EPRI Addresses 7 Myths of CFL Technology

Compact fluorescent lamps can be used in three-way fixtures and with dimmers. They also can last longer than incandescent bulbs when used properly.

U.S. retailers in 2011 are phasing out sales of incandescent light bulbs. The Energy Independence and Security Act of 2007 requires that between 2012 and 2014 all general-purpose light bulbs that produce 310–2600 lumens of light be 30 percent more energy efficient than current incandescent bulbs. While the law does not mandate the replacement of incandescent bulbs with compact fluorescent lamps (CFL), this is the technology widely available on the market today to meet the law’s target.

As consumers phase in the use of CFLs, they are also dealing with a number of misconceptions about the technology. The Electric Power Research Institute (EPRI) has addressed a number of these myths or misconceptions below.

1. CFLs cannot be used in three-way fixtures.
Most homes have at least one three-way table lamp. Several manufacturers have developed three-way CFLs to provide performance equivalent to the traditional incandescent lamps and to operate in standard three-way sockets. Three-way CFLs are available at most retailers with residential lighting inventories.

As with incandescent bulbs, three-way CFLs are offered in a variety of wattage and light output combinations. These include a 12/23/29 W CFL equivalent to the 50/100/150 W incandescent and a 14/19/32 W CFL equivalent to the 40/75/150 W incandescent.

Different manufacturers use slightly different wattages and lamp designs to match the output of traditional three-way incandescent lamps, and consumers are encouraged to try a few different CFLs to find the designs and output levels that best suit their needs.

2. Dimmable CFLs do not work with standard line dimmers.
Dimmable CFLs are available on the market today, but all dimmable CFLs are not compatible with all line dimmers. Also dimmable CFLs will have different dimming ranges, with some, for example, dimming from 100 to 10 percent, and some from 90 to 30 percent.

Incandescent lamps are frequently dimmed with standard electronic line dimmers — rotary, slide, and touch dimmers. Rotary dimmers are commonly found in older homes while slide and touch dimmers are typically installed in new homes, both for aesthetics and to provide additional features. Programmable dimmers enable the consumer to set the dimming range and are more likely to be compatible with dimmable CFLs. Dimmable CFLs that specify “true dimmability” are most likely to be compatible with most rotary and programmable dimmers. Before large quantities of dimmable CFLs are purchased for use with line dimmers, consumers should conduct a simple table-top test to determine CFL-to-dimmer compatibility, including acceptable dimming range.

3. Dimmable CFLs are hard to find.
Dimmable CFLs are becoming more widely available as the old bulbs are phased out. In 2011 dimmable CFLs can be found at most retailers, though in smaller inventories than traditional non-dimmable CFLs. Retailers follow lighting trends and know that dimmability will drive consumer choice. Dimmable CFLs will capture a growing share of the market and bring new options, such as incorporating the dimming control directly in the CFL base, eliminating the need for a three-way socket or wall-mounted dimmer.

4. CFLs do not last as long as advertised.
As with other electronic products, a CFLs’ lifespan is affected by its use. If installed properly, a CFL offers energy savings and longer life than incandescent lamps. To avoid cracking the CFL glass, consumers should hold the CFL by its plastic base when screwing it into a lamp socket. Installing CFLs in recessed can fixtures not rated for this use, will likely shorten the lamp’s life. Most reflector type CFLs are rated for use in cans, and some twist-lamp CFLs can be used in cans. Package labeling specifies whether a CFL can be used in recessed cans, and consumers should read packaging closely to determine suitability for this use. The life of a CFL also depends on how frequently the consumer turns it "on" and "off." Some manufacturers now list the recommended average number of daily switchings along with the rated number of operating hours. Switching on a CFL more frequently than the recommended average can shorten its life. Consumers who use CFLs with occupancy sensors will want to purchase CFLs with the longest life rating. When installed properly in appropriate fixtures rated for CFL use, CFLs reduce both operating and maintenance costs by reducing energy consumption for lighting and offering long life.

5. CFLs cause annoying flicker.
All lamps exhibit some level of flicker. In fact, all lamps exhibit two types of flicker. “Power frequency flicker” is more noticeable in incandescent lamps. CFLs operate at a frequency several thousand times higher, so power frequency flicker is not observable and causes no problem for consumers. Second, any lamp may flicker when the line voltage changes. This can be caused by large inductive loads, as when furnace motors are connected to the same electrical circuit. “Line voltage flicker” may or may not cause CFLs to flicker, and not all CFLs will have the same sensitivity, or exhibit an observable flicker in the same way.

Also, not all people have the same eye sensitivity to flicker. Some may notice flicker while others will not. The good news is that most CFLs do not respond to line voltage. If a CFL begins to flicker, it should be replaced by another brand to see if the flicker still occurs.

6. CFLs are too expensive, and savings in energy costs are outweighed by disposal costs - CFLs are hard to dispose of properly.
Over the past few years, the cost of CFLs has come down significantly as higher consumer demand has driven increased production. Other market factors include new, more appealing lamp designs, consumer education, low energy consumption, and increased retail access to a widening variety of CFL products. Increased demand has in turn driven innovative new products and an increase in the number of manufacturers serving the CFL market.

CFLs today contain only trace amounts of mercury, usually less then that found in a can of tuna, but it is still important to properly dispose of used or damaged CFLs. Consumers can easily find various safe disposal avenues through their local waste management provider – municipal or commercial – and through retailers that provide for the free disposal of CFLs, or via online resources like www.earth911.org.

7. CFLs do not fit in fans or candelabras.
Lamp manufacturers have developed CFL products of various wattages and designs that can be screwed directly into specialized fixtures such as fans, candelabras, chandeliers, and wall sconces.

Typically, lamps in fans and candelabras are highly visible and consumers value the aesthetics of the lamp when selecting a CFL replacement. Manufacturers now offer design options such as frosted glass, ”flame” lamps, curled lamp tips, and traditional incandescent shape.

The Electric Power Research Institute, Inc. conducts research and development relating to the generation, delivery, and use of electricity for the benefit of the public. An independent, nonprofit organization, EPRI brings together experts from academia and industry as well as its own scientists and engineers to help address challenges in electricity generation, delivery and use, including health, safety and the environment.