Advantages and Disadvantages of Using CFLs

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While CFLs are gaining in popularity, they have both advantages and disadvantages. Decide whether the advantages outweigh the disadvantages and if CFLs are right for you.

What are CFLs? CFLs are simply smaller versions of full-sized fluorescent lighting — the acronym stands for compact fluorescent lamps. The only difference from older versions other than size is that the quality of light is much better now than fluorescent light was in the past. Remember the ghastly white office lighting that drained everything of color? Today’s fluorescent lighting is much different and hard to tell apart from incandescent bulbs.

Advantages of CFLs

You hear about how great CFLs are, but one reason stands out: energy efficiency.

  • CFLs are up to four times more efficient than incandescent bulbs. You can replace a 100-watt incandescent bulb with a 22-watt CFL and get the same amount of light. CFLs use 50- to 80-percent less energy than incandescent lights.
  • While initially they cost more, CFLs are less expensive in the long run because they last much longer than incandescent bulbs. And since CFLs use a third of the electricity and last up to 10 times as long as incandescent bulbs, they are much less expensive overall. You will see a noticeable change in your electricity bills once you change over to CFLs.
  • You can do your part in reducing carbon emissions by changing over to CFLs. Just one bulb can reduce a half-ton of CO2 from the atmosphere over the life of the bulb.
  • CFLs are highly versatile and can be used in any setting where you would normally use incandescent bulbs. They come in enough shapes and sizes that you can use them for recessed fixtures, table lamps, track lighting or ceiling lighting. Three-way CFLs and CFLs that work with dimmers are also available.

Disadvantages of CFLs

CFLs also have their share of disadvantages and limitations. Most of them stem from the fact that not every bulb is suitable for every job, so it is more a matter of finding the right match. The only serious disadvantage is the mercury content in CFLs.

What Is Mercury?

Mercury is a naturally occurring chemical element that can be toxic to humans and animals. Fluorescent light bulbs contain a small amount of mercury, which can be released into the environment if the bulb is broken.

  • While CFLs are supposed to last about 10,000 hours, turning them on and off too frequently can reduce that lifetime substantially. They are unsuitable for places where you would turn on the light only briefly. These bulbs should be used only where they will be left on for a while without being turned on and off.
  • While you can buy CFLs for use with dimmer switches, not all CFLs can be used with them. Check the package before you buy. A regular CFL that is not meant to be used with a dimmer switch can burn out quickly. The same applies to using CFLs with timers.
  • When CFLs are used outdoors they must be covered and protected from the elements. They are also sensitive to temperature, and low temperatures can cause lower light levels. Check the package for suitability for outdoor use.
  • CFLs are not suitable for focused or spotlights or where narrow beams of light are required. They are meant only for ambient light.
  • While mercury doesn't pose any danger when the bulb is being used, it can be released if the bulb is broken or disposed of incorrectly. Please ensure these bulbs are disposed of carefully and take caution when doing so. The EPA recommends recycling fluorescent or CFL lightbulbs. Contact your local waste collection agency to find out how to recycle them.
Article Sources
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  1. ScienceDaily. “How Mercury Becomes Toxic In The Environment.” Accessed July 29, 2021.

  2. US EPA, OA. “Recycling and Disposal of CFLs and Other Bulbs That Contain Mercury.” Overviews and Factsheets, January 22, 2013.