Picture of a Example of a blue-colored Compact Fluorescent Light Bulb in operation.

CFL Advantages and Disadvantages

The energy-saving   CFL(Compact Fluorescent Lamp)   has taken the home lighting industry by storm over the past two decades.  It’s a smaller version of the ever popular straight and circular fluorescent tube light bulbs found everywhere over the last century.

Picture of a Example of a blue-colored Compact Fluorescent Light Bulb in operation.
Example of a blue-colored Compact Fluorescent Light Bulb Glowing

They make these lighting units much smaller today, and much brighter per inch of tube length besides, by employing electronic ballast technology; an approach that replaces the larger and heavier magnetic ballasts with very light circuit boards filled with miniaturized electronics and coils. Advancements in phosphor technology, electrode materials, and the mercury vapor gas inside, nave all culminated in a highly efficient, very quiet, and affordable light bulb.

But while this more efficient approach to operating fluorescent bulbs is cheaper to produce and ship, it has its drawbacks.  Often, thunderstorms can take out the sensitive electronic ballasts in these CFLs, as just happened in my home.  So here, I’ve decided to examine   CFL Advantages and Disadvantages, and am hopeful that I’ll discover more or less resolve to switch as a result of this study.

The overall performance and affordability of compact fluorescent bulbs has improved so much since 2000, that manufacture of traditional household incandescent lamps has essentially been abandoned here in the US.  They’re still made for specialized applications.  However the standard tungsten filament-based bulb is no longer produced.  As of this writing, stores are still selling these.  But that will continue only until existing stock piles are exhausted.

Advantages, Benefits, and Features of CFLs

  • CFLs Save Energy.  This 60 to 80 percent less power consumption than incandescent bulbs makes CFLs a godsend for aging and over-taxed power grids worldwide.  By reducing energy consumption by this degree, we can avoid (or at least delay) costly upgrades to municipal power distribution circuits.  These savings can also reduce dependence on foreign oil and overly rapid depletion of natural resources at home.
  • CFL Bulbs Offer Increased Reliability.  CFL technology has come a long way in the past ten years.  The fail less often, last longer, emit a more solid, flicker-free, full spectrum light, and more of them last as long as or in many cases, longer, than advertised.
  • CFL Lights Product Less Heat.  Since more of the energy drawn by a CFL is converted into visible light, less of it is converted into wasteful heat. This can lower air-conditioning costs in establishments and homes that replace many incandescent bulbs with CFL units.
  • CFL Light Bulbs Getting Cheaper.  As the CFL technology matures, prices are falling, and you can now buy packs of two, three, or six CFL units for significantly lower prices than if you bought each piece separately.  Discount CFLs are more widely available at larger home improvement centers and grocery stores like Lowe’s, Home Depot, and Walmart.
  • CFL Lamps Boast Longer Lamp Life.  Though many CFLs fail before their time, as has happened to us several times in recent years, in theory, they should outlast incandescent bulbs by several to as much as fifteen times if properly cared for.  They probably will last longer without being so delicate, once manufacturers make more robust the ballast circuitry.
  • Brighter CFL Bulbs Now Available.  The first CFLs put out much less light than the standard incandescent bulbs they were intended to replace.  However nowadays, they market CFL bulbs that more than adequately substitute for the 75 and 100 watt incandescent bulbs.
  • Better Color Choices with CFL.  Unlike incandescent bulbs, CFLs are available in several colors such as the 2700k (warm white), 3000 K (less warm white), 5000 K (cool white), and 6500 K (daylight white, which is a sky-blue shade of white).  Manufacturers attempted this with incandescent lamps but never got the colors above 3000 K or so, to work well.  Efficiency and life span of incandescent bulbs drop as you move their color output more toward blue.  CFLs are highly efficient however, regardless of color temperature output.
  • CFL Globes Fit Same Fixtures As Incandescent Light Bulbs.  You needn’t replace your standard light fixtures and lamps to take advantage of  CFLs.   With the lower heat output, a CFL can generally be used any place designed for a regular incandescent bulb, so long as the CFL itself physically fits into that space.  Further, since today’s CFLs integrate both the tube itself and the ballast into one unit, you needn’t retrofit your fixtures with any supportive electronics when deploying CFL lights.
  • 3-Way CFL Now Available.  The Utilitech #0346991 CFL unit for example,  replaces the 3-way incandescent bulbs, for under $19 apiece.  These are designed to replace the 50 / 100/ 150 regular 3-way bulbs.
  • Improving Technology Over All.  The electronic ballasts in a CFL bulb have improved in recent years; they generate less EMI, audible noise, and heat.

Disadvantages, Problems, and Concerns of CFLs

  • Overly sensitive electronics in CFL.  At the base of most any CFL light is a clump of circuitry that is responsible for lighting up the gas-filled glass tubes above.  This electronic ballast contains solid-state components that can be sensitive to voltage spikes arriving on the power line.  Lightning storms can create these spikes.  In fact, some storms that passed by here overnight took out two of our CFL lamps, and these were plugged into surge protectors as well. Sometimes, the surges can still get through however.  Regular incandescent light bulbs are less fragile when subjected to the short-duration pulses of nearby lightning strikes.  But CFL lamps are improving noticeably.
  • CFL Glass is Still Quite Fragile.  It still takes only a gentle bump against a wall or drop onto the floor from just a modest height, to shatter the spiral glass tubing that’s found in most CFL units.  Easy breakage is more of a concern for CFLs than it was for incandescent lights, due to the toxicity of the mercury vapor inside; a gas not used in traditional lamp bulbs.  So handle CFLs with care; even the spent units.
  • CFLs Can Generate Considerable Radio Frequency Interference.  Due to the switching nature of the included electronic ballasts, CFLs may interfere with radio reception; particularly on AM broadcast band receivers.  So radio buffs should carefully consider the choice to switch to CFLs.  Neither incandescent bulbs nor most LED lights generate this RFI / EMI.
  • CFLs Still Cost a Little More.  You can still get an incandescent bulb for under two dollars.  But CFL units can cost upwards of three times that much.  Yet often, they do not last upwards of three times as long as incandescent lamps.  We’ve yet to see any CFL last their advertised seven years.  Hopefully, they’ll become cheaper and more reliable in the next couple years.  But in the meantime?  That $15 we spent for them?  Gone!  And, the one was only several months old.
  • CFL Not Dimmable Generally.  Traditional light dimming controls that work so well with incandescent lighting, do not work well with many CFLs, unless you buy a CFL that specifically supports dimming.  Practically all incandescent bulbs and most LED bulbs support traditional leading-edge dimmer switches.  Over the past few years though, more “dimmable” CFL: bulbs have appeared.  But they’re  not as cheap as their non dimmable versions.
  • CFL Sometimes Do Not Light In Cold Weather.  Particularly in sub-freezing temperatures, a compact fluorescent lamp might not come on, as the mercury vapor gas inside does not as readily conduct electricity when cold.  However, both incandescent and LED bulbs instantly come on, full brightness, even in the deepest cold snaps.  Cold-weather CFL versions are available now, though for a bit more money, that feature circuitry that adjusts the amount of current flow in the arc tube.  It senses the external temperature and when it detects cold environments, the electronic ballast applies more voltage initially, to create more light.  Then, as the gas inside grows warmer, and conducts electricity more readily, voltages are reduced to prevent excessive brightness.  So, a more uniform brightness level is maintained from the bulb, over a wider range of surrounding temperatures.
  • They Can Take Several Minutes To Reach Full Brightness.  Again, this is especially true when the CFL bulbs are cold.  Neither LEDs nor incandescents exhibit this behavior, as they light to full brightness immediately.  This however, is fast becoming a non issue, as advances in electronic ballast control allow for better regulation of bulb brightness.  The ones we’ve tested recently achieve full brightness in less than a minute, when operated in average room temperatures.  Some CFL ballasts attempt to temperature-compensate for the initially cold gasses inside such that less dim starting occurs (more uniform brightness between first starting and warmed-up state).
  • CFL Should Be Recycled.  You can’t just throw away burned-out CFL lights, as they are considered hazardous waste.  Proper disposal of compact fluorescent bulbs means find a safe spot  to store them until you locate a recycling center or event to turn them in.  You can still throw away spent incandescent bulbs however.
  • Less Environmentally Safe.  Since CFLs should be recycled, and since appropriate recycling stations have not yet been set up in many market areas, the consumer must store them until such facilities become available.  While in storage, the consumer may accidentally break the CFLs, adding small amounts of mercury vapor to the environment.  Indeed, large-scale CFL use raises the risks of mercury contamination in our air.  No mercury in either incandescents or LEDs.
  • CFLs Will Become Obsolete Soon.  With the LED light bulbs fast coming up on the technological horizon, it may be unwise to invest heavily right now in CFLs.  CFLs are indeed more efficient than incandescent lamps.  But LED lamps are more energy-efficient, more rugged, and produce much less heat than CFLs.  So, reading the tea leaves now, it appears that CFLs, will enjoy limited long-term popularity, as they no longer represent the state-of-the-art of high-efficiency lighting.  So if you’re planning a lighting upgrade to CFLs, you may just want to go the extra mile, and instead, replace your incandescents with LEDs instead of CFLs.
  • CFLs Fail Early When Switched On And Off Too Often.  As with the more traditional fluorescent lamps, cycling them on and off more often than once in two or three hours, can cause premature CFL failure.  So once you turn them on, it’s best to leave them on for at least two hours.  Of course, this means that you’ll use somewhat more energy to keep your CFL bulbs properly conditioned.  LEDs are not at all sensitive to this, and incandescent lamps are less sensitive to frequent on-off cycling.
  • CFLs Sometimes Flicker.  Often, you see these compact fluorescent lights twinkling and “barber polling” in stores where there are lots of them, and sometimes, even at home when there are just a few.   Even when a CFL has warmed up fully, it still can flicker annoyingly, due to shifting paths of gas ionization inside the tubes as the internal temperature fluctuates.  If extreme care is not take in the design of the electrodes inside the glass, this problem can worsen.  This has been a long-running problem of fluorescent light technology, that has virtually never plagued incandescent lights or LEDs.
  • CFLs Currently Mean Fewer Domestic Manufacturing Jobs.  With the bulk of CFLs being manufactured in China, and incandescent bulbs being made at home, the switch to CFLs means fewer light bulb manufacturing positions here in the US.

Thus, considering all of this, our energy-savings strategy has, and will continue to incorporate SOME CFLs around the house here.  But we will not replace ALL incandescent bulbs with CFLs; particularly the outside lights. We’re still waiting for the LED lights to cheapen and increase in light output to match CFLs. At that time,  upgrades of all lights to LEDs will be completed.


Revision History

  • 2017-01-18: Targeted CFL more and adjusted the tags accordingly.
  • 2016-12-20: Minor updates, typo fixes, and addition of a featured image.
  • 2015-09-22: Added more content and tags.
  • 2014-11-01: Added pictures and more content.
  • 2012-05-03: Originally published.