All Hail the CFL
Kirt's Cogitations™ #231

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All Hail the CFL

Surely you have heard by now that compact fluorescent lights (CFLs) are the savior of the world. Thomas Edison's incandescent bulb is the devil. Australia announced back in February of this year (2007) that incandescent bulbs will be phased out within a few years. The stated goal is to cut greenhouse gas emissions by 4 million tons by 2012. According to one official, "If the whole world switches to these bulbs today, we would reduce our consumption of electricity by an amount equal to five times Australia's annual consumption of electricity." California politicians are pushing for the same policy for their state – Arnold “the Gubernator” Schwarzenegger likes da idea. European Union countries are seriously considering a ban on incandescents as well. Proponents there claim, “...if all inefficient traditional incandescent bulbs sold in Europe were to be replaced with more efficient bulbs - such as compact fluorescent lamps or CFLs - the continent would need 27 fewer power plants.”

Compact fluorescents consume about 20-25% the amount of energy per lumen that their incandescent equivalents consume. Depending on which manufacturer's product you buy, the light is usually whiter than that of an incandescent. In my experience, it is typically true for the 100 W and above models, but all the 60 W CFLs I have seen are annoyingly yellowish – almost like a low pressure sodium parking lot light. Here is a comparison of CFL versus incandescent according to information on the package of 100 W CFLs that I bought at Lowe's.

                                 CFL           Incan  .

 Output (lumens):   1600           1680

   Energy (watts):      23              100

         Life (hours):   8,000           750

                    Cost: $8 for 4    $1.5 for 4

Savings Over Life:    $61              $0

Melanie and I just moved into a new house that we were able to contract for prior to it being built. We figured it would be a good test platform for some of the newer energy efficient technology (for what our budget would allow). It is a split foyer design with all up-to-date building components and plenty of insulation in the walls and attic, an upgraded HVAC system, and good quality windows and doors. It has a little over 1,200 square feet upstairs, with a 2-car garage and unfinished living space underneath. One additional measure we took was to use all compact fluorescent bulbs in the light fixtures (except the outdoor fixtures). 60 W and 100 W CFLs were used.

Since our old house had all incandescent bulbs, it was fairly easy to make a comparison on the quality of light. Both houses have roughly the same size and color walls and ceilings (off-white), as well as light fixtures with the same number of bulbs. There is no doubt that the CFLs do not illuminate the rooms as brightly as the equivalent incandescents do, and the color of the light overall is noticeably yellower (even for the 100 W). The lumens might be equal, but the spectral distribution of a lot of the energy must be in places that my eyes do not respond to. It is hard to resist the urge to throw away the CFLs and replace them with incandescents, but for the sake of single-handedly saving the planet, I will learn to live with them… unless it drives me totally nuts. Sure, I could add additional lights to the room or put in larger (and very expensive) CFLs, but doing so would defeat the purpose of using CFLs and besides, some day in the not-too-distant future the light bulb police will be threatening me with jail time if I do not comply. Resistance is futile.

So, with all the good that compact fluorescents are going to do the world, is there no downside to using them? In fact, there is. Just as with the long, tubular fluorescent bulbs you have seen for years in office ceilings, stores, and in your workshop at home, these CFLs need a pinch of mercury (turned into a mercury vapor by a high voltage arc) to cause the fluorescent material in the bulb to glow. How much mercury? Per a very recent NEMA ruling, "Under the voluntary commitment, effective April 15, 2007, participating manufacturers will cap the total mercury content in CFLs under 25 watts at 5 milligrams (mg) per unit. CFLs that use 25 to 40 watts of electricity will have total mercury content capped at 6 mg per unit." Incidentally, the Hg content limit is what ultimately also limits the lifetime of the bulb.

Bonus Fact: Mercury's chemical symbol, Hg, comes from the Latin word "hydragyrum" which means liquid silver, due to its color and phase state at room temperature.

Mercury is a potent neurotoxin with the potential to build up in the food chain. The EPA and FDA in the United States prohibits or greatly restricts mercury content in everything from building materials to processed tuna fish. You have heard, no doubt of Lewis Carroll's Mad Hatter (or the saying, "mad as a hatter”). Hat makers of yore used mercury nitrate as part of the felting process; it famously over a career left them loony. It only takes 1/70th of a teaspoon of mercury (about the amount of Hg in a typical medical thermometer) to contaminate a 20-acre body of water and make all fish within it toxic to humans. 1/70th of a teaspoon equals about 970 mg, which is approximately 194, hundred-watt CFLs. I have not seen a calculation showing how much mercury would need to be mined and then disposed of once the entire world converts to fluorescent lighting. Some pro-CFL sites like to demonstrate how the mercury put into the air by electric generation plants to supply the additional energy used by incandescents is greater than that used in the production of CFLs.

Hopefully, the entire debate will be made moot with the advent of high power LED lamps. Both incandescent and fluorescent lamps could be made obsolete by the kinds of advances that are being reported for LEDs. The Science Daily website has run many stories in the last couple years on the topic. From what I have read, there is no as-yet identified down side to LEDs either in the manufacturing process or in the disposal thereof. One advantage to LED lamps is that typically they are constructed from an array of individual LEDs, so that a graceful degradation of the output occurs rather than a wholesale failure. It is not uncommon to see commercial truck tail lights with one or more LEDs from the cluster not working, yet the tail light is still useful.

As with all of these kinds of debates, the extreme proponents are as wildly vehement about their call for the complete abandonment of incandescent bulbs as the extreme opponents are about keeping their beloved Edison models. I think that a lot of the rejection of new paradigms like adaptation of alternative lighting, fuels, etc., is caused by the over-zealous, in-your-face, I'm-smarter-than-you attitude by the early adopters. Usually those people have no credentials for their nearly militant efforts at evangelization; they are simply regurgitating what they have heard from some other non-credentialed source.

I am personally an environmentally friendly person and do what I can within reason to help preserve the health of Planet Earth, but nothing makes me want to go buy a Hummer more than watching Al Gore pontificate about how he lives a carbon neutral life by virtue of purchasing "carbon offsets" to atone for his excessive lifestyle.

Fluorescent Light Bulbs Can Become 'Toxic Time Bombs'

Please make your comments on the RF Cafe Forum (CFL vs. Incandescent Debate).

Posted April 6, 2007