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Friday, October 3, 2008

This was not the right application for a compact fluorescent light

Several months ago while talking with Cary Eskow of Lightspeed, he mentioned how important it is for the LED lighting industry to carefully frame the applications suitable for solid-state lighting and not try to pretend that LED lights are the perfect lighting solution for every problem. He used the CFL (compact fluorescent light) bulb as an example of how not to introduce a new lighting product. A variety of agencies, from government to utilities to lighting manufacturers, have presented the CFL as the perfect energy-efficient light source. Homeowners should replace all incandescent bulbs with CFLs; The initial higher price of CFLs was more than offset by its energy savings over its longer liger life.

There’s been a backlash against CFLs -- especially since the federal law was passed last year that mandates the replacement of all incandescent bulbs by 2012 -- by users complaining that the lights have a shorter life span than advertised. (There’s also concern over CFLs mercury content, but that’s a discussion for another day.)

My personal experience is that CFL lifetime is influenced by its application. Several months ago in a PowerSource post on dimmer circuits for a CFL I mentioned in passing that I had had poor luck with CFLs burning out early, and several readers commented on their likewise poor CFL lifetimes.

CFLs that are installed in either down lights or ceiling globes in my house have a much shorter life than those installed in a table lamp. A table lamp is probably the most benign environment for a bulb because the heat goes directly up without affecting the CFL bulb's electronics, which are placed in the base. In a down light, the can around the bulb tends to confine the heat to the bulb, causing it to run hotter and I assume shortening its life. Plus, because the bulb in upside down, as the heat rises it makes the bulbs electronics located in the base run hotter than it would in a traditional table lamp configuration.

I shot the temperature of a downlight CFL with an IR gun and got a reading of 160°F at the base, while the table lamp CFL was at 120° F -- a big difference and one that will affect the life of the electronics in a CFL, including transistors, which don’t like operating at higher junction temperatures.

Here’s a photo of the innards of one of the CFLs that failed: Note the brown, too-hot-looking marks on the plastic base. (If you want to take a part a CFL yourself, I recommend the how-to article at Instructables.)

Inside a CFL

Like any fluorescent light, a CFL is a gas discharge tube. It relies on an inductor acting as a ballast (the yellow/blue square) to limit the AC current through the tube. Because the inductor would have to be unreasonably large if the CFL operated at the line frequency of 60Hz, the CFL’s circuitry includes a frequency multiplier stage relying on several high-voltage transistors that enable the use of the smaller inductor at the higher frequency.

CFL pcb showing handwork

(Here’s a close-up of the pcb that shows the handwork on these lights that sell (my cost) for about $2. All that handwork means more opportunities for inconsistencies that can lead to increased failure rates.)

If you go to the Energy Star site, it now has caveats on using CFLs.

“How to Choose and Where to Use CFLs

ENERGY STAR qualified CFLs provide the greatest savings in fixtures that are on for a substantial amount of time each day. At a minimum, ENERGY STAR recommends installing qualified CFLs in fixtures that are used at least 15 minutes at a time or several hours per day.

CFLs perform best in open fixtures that allow airflow, such as table and floor lamps, wall sconces, pendants, and outdoor fixtures.”

In my house I have all of two table/floor lamps that meet Energy Star’s criteria for where CFL’s perform best.

I have to agree with Eskow that the CFL proponents have done a poor job of setting the stage for CFLs as a universal replacement for incandescents. If CFLs have a shorter life in some applications and should be selected with care, or specialized versions should be used, then that information should be made clear and emphasized.

In the meantime, I use CFLs where they are appropriate, and I look forward to LED lighting that both sips power and has virtually no pollution.

Related entries in: LED | Power Consumption | Power Sources/Controllers |

Reader Comments

(Add your comments)

at 10/3/2008 2:25:31 PM, Jonathan Williams said:
Agree. Now, how do we go about getting Congress to strike that ridiculous law? I use them in certain high duty cycle, benign environment applications, but I am loathe to replace the incandescents in closets, attics, candelabra fixtures etc.

at 10/3/2008 2:42:44 PM, Dale said:
We initially had short CFL lifetime problems, but then we read that fingerprint oil could shorten a CFL's life. Since we've been careful to never touch the tube itself, we've had very good lifetimes. Most of our CFLs are in down lights. Maybe we just got several bad ones in a row, but we'll continue to use a cloth to install them.

at 10/3/2008 2:43:50 PM, sandsa@pacbell.net said:
Incandscents, from my experience, have a shorter life when turned on and off abruptly. i.e. like most of them are, with a switch. The sudden inrush causes an abrupt mechanical expansion than can shorten life. I use CFL''s when I want one level of lite only. Otherwise,I use Incandescents with dimmers(the rotary or lever type WITHOUT push-on-off switch) and get better life than CFL''s. The filament is heated (relatively) slowly. With dimmers I can also get a different level of light as needed at different times of the day and night. By dimming incandescents we can set the mood from bright to "romantic". I hope they don''t rule out candles next! Edward Smith

at 10/3/2008 2:51:36 PM, Policebox said:
Would someone please explain how this impacts LEDs? The suggestion is obvious, but there are no details. LEDs use less power than CFLs (not including drive electronics), and so do not generate as much heat. Do they still generate enough to cause age effects? LEDs are not discharge devices, but they require a high efficiency regulated current source to maintain their energy edge. How does this difference impact the argument? This article seems very incomplete. If you are going to say they need to stage their introduction, you should say why. The fact that the CFL introduction was botched is a good reason to check. But if nothing shows up in the check, you've wasted your time making a fuss. Do the check first, then make a fuss if something turns up.

at 10/3/2008 2:56:21 PM, tommy said:
Good things that work well usually do not need laws passed by a congress that can''t seem to get anything right, like my low flo toilet that I must flush 2+ times. Engineer it right, market the truth and the buyer will recognize the value. Congress = low value Good engineering = Great value

at 10/3/2008 3:04:06 PM, jhcatch22 said:
It is mentioned that the transistors are likely to fail in the higher temperatures, but I would argue that the aluminum electrolytic cap seen in the picture above is the most likely item to fail in the CFL. Regardless, I have had a couple of smoking CFL failures, and it was a good thing I happend to notice the smoke before it became incendiary! My first choice is still incandscent with dimmers.

at 10/3/2008 3:49:22 PM, Lyeal said:
As I see it CFL devices should have been designed in the first place with appropriate margins on the parts so they could be operated in any position, in enclosed or open fixtures and still meet their long life hype on the packaging and elsewhere. I agree that Congress was nuts to ban incandescent lamps as others have pointed out the reduced power and long life with dimmers. Another approach is to buy 130 volt lamps which also last much longer but do give less light output.

at 10/3/2008 3:56:59 PM, skeptic about skeptics said:
Interesting article, but based on my experience and my friends, the implication that CFLs are over-sold is not warranted. The right question is not "will the CFL last for the advertised life," but rather "will the CFL last for long enough to have electricity savings that outweigh the initial cost?" And the answer is "Almost, always, yes." CFLs are heavily subsidized: 3 for 99 cents last week at Walgreen, for example. Power savings for the "100 watt" size are 70 watts x 28 cents per kwh (I was shocked, but that's what my San Diego electric bill showed.) That's 2 cents per hour. So if a bulb lasts 500 hours, that is a savings of $10, minus 30 cents initial cost. And almost every bulb lasts _several thousand_ hours, in my experience. Now factor in the labor time to change inaccessible light bulbs less often. Result: I use CFLs in EVERY non-dimmer installation in my house, including outdoors. I change a light bulb about 3 times a year, so far.

at 10/3/2008 4:07:14 PM, claudepgh said:
I have purchased some LED lights recently that have fairly good performance. One of them I put in the outside fixture above the porch and because of its low power consumption (3.5 watts) we leave it burn 24/7. It produces lots of light and almost no heat. Keep in mind that motion controlers will kill LED and CCFL lights because they are using a Triac which distorts the AC. This automaticly shortens the life of these new light sources. There are more than a few wrinkles that need to be worked out to make them perfect. Lights of America is who makes my test subjects. I have split them open and analized the circuitry. Anyone who is curious about how they are designed is welcome to ask.

at 10/3/2008 4:26:03 PM, Chris P said:
Apparently if you buy the wrong brand they don't work well. If you bought Philips CFLs - I have never had one go bad. Instead of saying that all CFL's are bad because you bought the wrong ones why don't you do some research on all brands first. People in the US are far to quick to buy cheap crap and then whine when it doesn't work.

at 10/3/2008 5:18:20 PM, Earld said:
I replaced all of the incandescent lamps in our house with CFL's 6-7 years ago. The electric bill dropped at least $20 every month. 2 of the original Phillips lamps, at $16 ea. are still operating. The failures have been infrequent. proper disposal has been to only problem. I'm waiting for LED's,

at 10/3/2008 5:51:46 PM, Bill K said:
Claims of 5 to 7 years life have never been met even with the more expensive older style units in my experience. The general public should not have been enlisted to replace all incandescents when the lamps have serious disposal problems and now the net cost is higher just to buy and throw away before energy savings are recovered. The fragility alone is a health issue that outstrips the energy savings.

at 10/3/2008 6:11:41 PM, TomNewYork said:
I too have had mixed results with CFL life. Some, COSTCO, have had high infant mortality. My main concern is the effect on the power grid when almost all the incandescent lights, and their resistive loads, are removed from the grid.

at 10/3/2008 10:58:29 PM, Gopal Darbari said:
Yes, the problem is accute and must be handled very carefully. But the problem with LED''s is not so simple. LED''s must be kept cool to get the right life. LED''s require heat management more accurately than electronic ballast used in CFL. Therefore, unless the heat is properly managed, LED lamp life will be shortened drastically.

at 10/4/2008 2:00:21 AM, cacudi said:
Policebox, Power LEDS (that I sell for a living) DO age: the best have an half-life of 50,000 hours (meaning, the time at which the lumens they generate become half). The decay is slow and begins immediately. Also, the light is not broad spectrum and contains some blue which is dangerous to look into. The warmer ight versions are less efficient and tend to veer towards cooler light with time. Heat is a special problem: Incandescents emit a lot of thermal (infrared) radiation, A LOT (proportional to the CUBE of absolute temp), and this brings heat away from the bulb. LEDs do not, light is cool. This is good, but you have to be extra careful to put GOOD heat sinking right behind the chip (if you don''t, these 50,000 become much much less, maybe even 10,000). Very few now do it, be it for being ignorant or because they want to have the same shape factor as with halogens at every cost. Some put the sink but later enclose the whole thing in a ceiling recess, making it useless - and then blame the manufacturer. Another great problem is that the lighting guys are attuned to cheap power supplies full od uncontrolled transients and spikes, harmless on lamps but deadly on LEDs. Thst''s why I am leaving this field of bozos and changing activity. Do not cringe for your prices. 2-3$??! Here in Europe we pai min. 9 euros for a 18W! You guys are all very spoilt.

at 10/4/2008 10:19:20 AM, Ed said:
I''ve used CFLs for years both in bulb down and bulb up installations. I mark on each bulb the date purchaced and date placed into service (I keep copies of sales slips to return bulbs that burn out before they should. You send back a copy of the receipt and the package info and receive a credit to purchase new bulbs.) I also sometimes date when the bulb is taken out of service due to failure to ignite, hum, whistle, burning smell, etc. I see about 3 year life in bulb down and perhaps 3.5 to 4 year in bulb up applications. In continuous burn applications (yes, I''ve used the 5w appliance bulbs in exit signs contrary to directions, but the box is large enough to dissapate the heat) I get about 10 - 12 months) Bulb is rated at 6000 hours, so you get what you pay for. I''ve never seen one that lasted what the mfgrs claim, either they use a much shorter time for burn/day or the power on/off cycles catch up with the cost reduced components.

at 10/4/2008 4:59:53 PM, Ken Sydney Australia said:
Three things concern me about CFLs. Firstly due to the large base they will not fit into some of my holders. Secondly the highest power CFD seems to be 18W and gives much less light than a 100W incandescent. Thirdly I am wary of the stroboscobic effect of any flourescent lamp which can make moving machinery appear stationary. OK that is rare but the consequences can be serious.

at 10/6/2008 4:28:28 AM, Darren Holdstock, UK said:
Ken - all valid points, but I can at least reassure you that CFLs don't flicker, at least not once they're warmed up. Unlike the old fluorescent striplights running at 50/60 Hz, CFLs run at 10s of kHz, and there's a sufficient phosphorescent time constant to maintain a continuous glow. However, you'd ideally still want an incandescent in your machine shop, as a CFL safety light that takes a couple of minutes to warm up (and even then gives a poor colour spectrum) is just a liability. Time to start stockpiling filament bulbs while they're still available.

at 10/6/2008 7:09:48 AM, Lightpro said:
I've designed Fluorescent lamp ballast for a large company. The brown marks can come from an end of life condition that occurs when the filament heater emitter is used up. It is called end of life and ANSI and IEC have end of life requirements. Essentially when the emitter material is used up the power to the lamp increase and most of it is dissipated at the lamp ends heating the glass near the filaments. The blacking at the ends is the material on the filaments deposited on the glass. Usually a lamp at end of life will have either a yellow or red glow near the failing end. I also agree that the electrolytic capacitors are usually the failure mechanism and related directly to temperature

at 10/6/2008 7:27:52 AM, W17053 said:
I still wonder what to do for my Oven and Refrigerator when incandescent are banned. I don't think using a mercury filled bulb is a good idea, but then again I am not a Congressman.

at 10/6/2008 11:39:06 AM, Mark said:
I have found LightsOfAmerica CFLs perform substantially better than FEIT. Many FEIT CFLs I have purchased (often for <$1 for a 100W equiv.) lasted less than 6 months on 2-3 hours per day. CostCo sells only FEIT and I plan to write a letter to them explaining how badly FEIT lights perform. To their credit, FEIT has replaced bulbs I have shipped back to them. However, it costs me $4-8 to ship them the burnouts so I loose money. Another issue I've found with the really small CFLs (e.g. the ones you can put in a chandelier) is that it takes many minutes for them to 'warm up' to full brightness. So, when you first flick on the switch, you get only a very dim light that then slowly gets brighter. I have also used dimmable CFLs and have found that they really don't dim to low light levels well at all and often flicker at low light and cause interference with my cable television. I don't recommend 'em. I've recently tried LED PAR 38 floods. The first lasted 3 months before totally going out. The company shipped me a new one. We'll see how long it lasts. It was a $13.00 bulb! For sure, CFLs and LEDs have a long way to go before they actually fullfill the promises on their packaging. I don't think I have saved any money yet. But, I have saved watts and I value that savings.

at 10/7/2008 7:53:13 AM, John said:
Maybe we should go to these: www.centennialbulb.org/

at 10/7/2008 8:58:30 PM, Tiptilix said:
I think that the correct way to answer the question is: "Does the CFL disadvantages outcomes the advantage of "low" consumption?" And I say that because it seem forgoten that the CFL is PULSING device, while the incandescent bulb, due to the thermal innertia has almost no pulses. I where glasses and I do not need to actually see the bulb type to tell you that it pulses. CFL hearts people''s eyes. And the bill will not be pyed by the CFL manufacturers. After me, the right use for CFLs is where you do not realy need to see details.

at 10/8/2008 9:23:50 AM, The Doctor said:
>>As I see it CFL devices should have been designed in >>the first place with appropriate margins on the >>parts so they could be operated in any position They probably *were*, originally -- but as with everything else in consumer electronics, it all gets outsourced to China and from there it's a race to the bottom as the Chinese manufacturers start trying to skim a few extra cents off the top of each unit sold by substituting cheap components of dubious pedigree whose "absolute maximum ratings" barely meet the expected *normal* operating conditions.

at 10/9/2008 1:15:48 PM, FarFetcher said:
The part I don't like about a ban is the lack of exceptions. Will the CFL work well outdoors at my Vermont ski house? Fumbling for a key without light in -20 F is not my idea of fun. A suggestion to put it in a globe may help somewhat, but what happens in the summer when the light is left on? I don't want to be changing the fixture to suit the bulb. Perhaps a reader with access to a temperature chamber could run a test and report the results.

at 10/9/2008 1:44:21 PM, Dufus said:
Here is another example of the US Congress sticking their noses where they shouldn''t. 1.- CFL may as well work outdoors for geographical locations where the average temperature remains above freezing. However, they are lousy -in the winter- if you live in the northern states. 2.- The mandate by Congress failed to "mandate" cities, towns and municipalities to create an efficient and accessible disposal for CFLs due to their mercury content, and that hasn''t happened and won''t happen any time soon

at 10/9/2008 1:56:06 PM, Kalos said:
For applications where CFL is not appropriate, halogen lamps give a useful 10%~25% efficiency improvement over ordinary incandescents. For this reason, sometimes a lower wattage halogen can be used in place of a higher wattage regular incandescent - especially where a clear halogen lamp is substituted for a frosted incandescent behind a frosted globe. Amazing how many people put frosted bulbs behind frosted globes and then wonder why the light is dim.

at 10/9/2008 2:09:44 PM, jeffreagan said:
I've had bad luck CFLs in bathroom and hallway lighting applications. These areas only require momentary lighting so the bulbs are required to go off and on all the time, which should shorten cathode life. Also in the dimmer application, I've noticed incandescent bulbs last much longer than those that are switched on in the normal manner. This should be true for two reasons: the dimmer ramps up the voltage thus avoiding the inrush surge-flash phenomena. Also the dimmer doesn't pass the full RMS voltage. Dimmed bulbs stay in service with excellent life in the applications I've seen.

at 10/9/2008 2:57:17 PM, Chris P said:
I have cfl's outside where it gets down to -35F. In the bathroom - in fact everywhere including spots. NO troubles. You guys are buying the wrong ones. Margery appears to represent the usual whiny stick in the mud American who doesn't understand their effect on the planet. Probably whines about recycling too.

at 10/9/2008 3:00:30 PM, Gregarious2 said:
Rocky Mountain Institute has an interesting paper comparing CFL with incandescent ( www.rmi.org/images/PDFs/Climate/C08-02_CFL_LCA.pdf ). Unfortunately, they missed a few technical issues mentioned here. After 10 years experience with CFLs at home and in work apps, I currently use dimmable halogen task lighting and love it. At .44/kwh, I would like a more efficient light source but CFL operation doesn''t fit my use profile. ( I rarely sit around with general room lights on for an hour or more.) I''m trying 5 watt LED MR16s in a few places and have been pleased so far.

at 10/9/2008 3:09:26 PM, henry said:
I just changed my dimmer fixtures over to CFL's. The problem is that they take several minutes to stabilize. CFL's work really well in lights that stay on for extended periods. Here in Southern California there isn't the cold temperature problem. When my family first began using CFL's the color temperature was terrible. There are now warm, bright, and daylight. They are much better. Warm CFL lights are also great for plant growth.Try that with an LED or regular light bulb and you get bad results.

at 10/9/2008 3:17:37 PM, Ray said:
I have tried several brands. One 'off brand' from a local supply house and GE brand. The GE brand comes on immediately and at full brightness. The other takes several minutes to come up to full brightness. I have about 8 of the off brand and all are the same. They slowly increase in brightness. Not good. I had some higher 150W wattage off brand a year ago, in a downward position, that go so hot after about six months use, I was sure it was going to catch on fire. So brands are different.

at 10/9/2008 3:24:07 PM, Rex Niven said:
What components actually fail in a CFL at end of life? Maybe it is the tube itself, or soldered connections. Your analysis seems to assume that a PCB-mounted part must be the problem.

at 10/9/2008 3:24:17 PM, Paul said:
I almost exclusively use CFLs, I have used CFLs and the circular fluorescent adapters that fit in Edison sockets since the early 1980s. The new cheap CFLs do not last as long as the vintage ones. I still have a few CFLs from the '90s which work reliably, but I have gone thru boxes of new CFLs. The magnetic ballast circular fluorescent adapters I bought in the 1980s still work fine, with a slight delay before they turn on. I hope that LED bulbs have improved reliability, since of the two that I have tried, one lasted 2 weeks, the other is not very bright. Indoor mercury is an issue, since the CFLs often fail with cracked glass, perhaps due to thermal cycling.

at 10/9/2008 4:21:47 PM, Alex K said:
Installed CFLs in every socket in the house. Removed globes where necessary, Installed shades/filters to correct the glare. Very noticable improvement in our electric bill. Did the same in our small business. Only a few replacements so far. Keep the law. Looking forward to LED, as well as better CFL though.

at 10/9/2008 5:30:03 PM, JAMES TYRER said:
The author seems to use the term CFL to referr to the screw in replacements with integral ballasts. Yes, there are problems with these. OTOH, the CFLs that have separate ballasts don''t have these issues. The better solution to the problem is to retrofit lamps to use CFLs rather than using the screw in replacements. There is issues with this. The ballasts cost more, but last longer. It is almost impossible to find sockets that are suitable to directly replace sockets with 1/8" pipe thread. For portable lamps, a wall cube ballast seems to be the answer. These seem to be unavailable. Perhaps what is needed is to develop better products to permanently retrofit light fixtures.

at 10/10/2008 12:17:56 AM, ELH said:
I''m surprised to notice that none of the commentaries have brought up the fact that CFLs have extremely poor power factors. Let me explain a little more. few weeks ago I conducted some measurements on the quality of power drawn by 7 different types of CFLs. First thing to notice was that while the actual drawn power was as stated on the label, they actually consume nearly as much the same amount in parasitic power. From my notes

at 10/10/2008 12:20:25 AM, ELH said:
My earlier post seemed to have cut a bit torso, sorry for that. Here's the whole comment: I'm surprised to notice that none of the commentaries have brought up the fact that CFLs have extremely poor power factors. Let me explain a little more. few weeks ago I conducted some measurements on the quality of power drawn by 7 different types of CFLs. First thing to notice was that while the actual drawn power was as stated on the label, they actually consume nearly as much the same amount in parasitic power. From my notes; 23W CFL had 40.8VA apparent power, 13W had 23.6VA and so on. Roughly the power factors varied between 0.57 and 0.63. Now, that's not even the ugliest thing about them. When you look at the waveform of the input current, what you will see, is that the current is a sort of high spikes that have amplitude values typically over 8 times the incandescent bulb of same wattage. The 13W CFL had a 1.2A peak current value! Incandescent bulb with the same peak value and PF=1 would be rated 195W! If a situation is reached where ALL the lighting is done with CFLs you will soon have problems like interference in other electric equipment caused by high pulsating currents in wiring, circuit breakers tripping because of high amplitude currents, AC waveform 'flattening' and network transformers overheating because of increased parasitic current and harmonics. In other words: a disaster! And in my experience, when you group more than few CFLs in same place they start to die early, probably because of mutual interference. Some of these problems might be less in 110VAC systems, but I fear the case is the same as with 230VAC.

at 10/10/2008 6:44:33 AM, JWL said:
I think a lot of us have missed the issue with CFLs. Yes they have cathodes but these cathodes are a filament at initial start just like a regular flourescent tube. Heat the mercury vapor to start electron conduction then the higher frequency ac voltage takes over. WHAT does burn out is the filament (cathode) because hot spots develope in it just like an incandescent lamp. This happens more often then the electronics burning out. Just take one apart and carefully break the tube without cracking the glass at the filaments you will see the filament which is thinned out slightly where this hot spot developed. Hey, but don''t throw away the electronics they 13 watt one will drive up to a 36 watt U tube fluorescent tube!

at 10/10/2008 7:52:04 AM, HTR said:
Have these devices been given a look by the FCC? They have been known to interfere with X10 devices. EMI/RFI concerns for communication equipment? No one else has posted any RF interference concerns. When the whole world is CFL, what will be the condition of HF communication bands with respect to noise levels? If it is such a great idea, why does congress have to mandate? Wouldn''t market forces do the job?

at 10/10/2008 12:28:02 PM, Mike Bibby said:
Darren has put his finger on the simple solution. In reckon I've got about 20 years left - so I've stocked 30 years worth of incandescent bulbs just to be on the safe side!

at 10/10/2008 1:04:47 PM, Matt said:
My house had 25 built-in light fixtures. Twenty years ago I decided to try CFLs. Only three fixtures could handle them. Why? The CFLs of that time were much bigger than the incandescents. They could not fit in most fixtures. And now the manufacturers are more honest about another problem. On the package or base of most they state "Not for use in totally enclosed fixtures." Of course, this is in the finest print. The electronic circuitry in the base needs good ventilation. I had one burn up when exposed, but with ventilation impeded.

at 10/12/2008 11:39:23 AM, Richard said:
We built our present house and occupied it in March, 1996. At least two thirds of the original incandescent bulbs are still in service. I've replaced the bulbs where lights are on for prolonged periods with the screw in CFLs and none have lasted for more than a couple of years. My wife and I do a lot of reading and we find the CFLs blur the print. We have decided they are unsuitable as reading lights. Perhaps this is an age thing as we are in our mid 70s. Another thing: we installed some high quality european made light fixtures. Beautiful, but the CFLs won't fit in them. If the law is not repealed, we'll be forced to buy a good supply of incandescent bulbs as backups.

at 10/14/2008 9:19:25 AM, Darren Holdstock said:
Richard, it's not your eyes, it's the CFL bulbs. Take a look at the CFL output spectrum [ioannis.virtualcomposer2000.com/spectroscope/amici.html] compared to sunlight or an incandescent bulb, and you'll see why. Also, the "equivalent power" rating is a lie - CFLs are always noticeably dimmer than the incandescents they claim to be able to replace. HTR has a valid point about EMI, and it's something I fed back to Farnell when they discontinued every single incandescent they had. I have two CFLs in my house, in hallway areas where their main function is just to stop me tripping over cats, and I have to turn them both off if I'm making a recording from FM radio. They're the worst source of continuous interference in my home, and if the incandescent supplies dry up completely I'll have to do my EMC chamber work by candlelight.

at 10/14/2008 1:23:14 PM, Roger said:
CFLs are great EMI/RFI polluters. They make more radio-type noise than some computer monitors. Tune a portable AM radio to an unused channel and hold it about 1-foot away and then turn the CFL on. CFLs may be incidental energy savers but they pollute in more ways than one. The fast-switching power transistors you mention cause harmonics to be radiated and coupled to the AC power mains. Those harmonics when multiplied by thousands create an electeical grid problem no one is talking about. For the full scoop search for a report on CFLs by Parsons Brinckerhoff Associates "Installation of Compact Fluorescent Lamps - Assessment of of Benefits" written for the Electricity Commission of New Zealand. The US government allows an inferior quality of lamp to be sold in the US. I am advocating the rejection of CFL use until a high quality lamp available and the lower quality lamp is off the market.

at 10/14/2008 1:39:36 PM, Ed Best said:
The real issue is that there is no single lamp source that will meet all needs. In my more than 30 years as a lighting designer I have used a broad range of lamp types as the application demands. Wrongly the public has decided that "energy efficacy" is the only important criteria for lighting. That's just a foolish approach. Be aware that the LED folks are going down the same path! Lamps need to be selected by application, time of operation, orientation, etc. There is no single solution!

at 10/14/2008 2:03:09 PM, rodxtal said:
I use CFLs everywhere they will fit, and have even replaced several fixtures to use them. My favorite reading lamp is a "daylight temperature" u-tube model. Expensive, but the color is better than the 60W incandescent that it replaced. There are also dimable CFLs that work well, I''ve been using a pair for about a year. BTW: an incandescent on a dimmer is less efficient than otherwise, due to the lower temperature. A greater percentage of the Planck curve (we''re all engineers here right?) slips into the infra-red. The dimmer also has losses due to heat and generates some EMI. I do have to agree though about the equivalent power and MTBF claims being exaggerated, but these are the time we are living in.

at 10/14/2008 2:06:29 PM, sbkenn said:
Incandescent lights are cheap to produce, cause little pollution in their manufacture or destruction, and in cold weather, the heat generated isn't wasted anyway(unless they are outdoors). Their inefficiency in producing light is only relevant in hotter weather, or where there are lots of them. LED's, hopefully will overcome those reservations, but from what I have seen, the really high power ones don't actualy have THAT long a life anyway !.

at 10/14/2008 2:25:08 PM, HZF said:
Does anyone know how long the CCFL has to be in use before the energy associated with manufacturing it is paid back? What's the carbon impact vs leaving the original bulb burning until is goes out?

at 10/14/2008 3:01:49 PM, pgdion said:
Actually the biggest factor on CFL lights is the brand you choose. I bought some cheap imports intitially (buyers choice and some brand that starts with an F). I had some failing after only a few months, a couple were bad out of the box, and one failed at first power up. I only buy the name brand now and I haven't had to replace any of them yet (I usually buy Sylvania but all name brands have held up well). I switched to CFL's almost everywhere in the house about 2 years back and it was clearly the best move ever. The energy saving is very noticeable from this one move alone. There are only a couple of places I don't use them such as in the recessed flood lighting in the rec room downstairs where I like the low dim of the flood lights for watching movies. Everywhere else, the CFL's are great.

at 10/14/2008 3:41:24 PM, Rod Schwartz said:
Good article. You mention LED lights and indicate they are lower power. Be careful with this since the ones I have tested are lower current but with terrible power factor (~1.7). This means that all your savings and more go out the window because of high peak currents. The best use for LED lights is in cold environments (cold storage plants, etc.) or hard to replace areas.

at 10/14/2008 8:39:41 PM, Jeff said:
I find that while the CFL's that I have installed are short-lived in downlight applications in general, they are fine in the closets and attic where the light is only on 5 - 10 minutes at a time. For the living areas of the home, I still use (and will continue to use) incandescent bulbs because they are brighter, longer lived, and less expensive. I plan to have a stockpile of those in the house long before they disappear from the shelves at the store. Congress has no business banning anything from us, but since we probably can't stop them, load up while you can.

at 10/14/2008 11:58:41 PM, WestfW said:
Hey; thanks for the pointer to my "Instructable"! Has anyone done any actual failure analysis on dead CFLs? I've dissected bulbs with noticeably swelled electrolytics, burnt resistors, and "open" PTC varistors, but I haven't tested the semiconductors, and I'm real unsure of the cause-and-effect relationships. I mean, I know that caps are known to have shortened lifespans at high temperatures; do the caps go bad with the resulting high ripple blowing other things? Or do other things blow first? People can't design a better CFL til we have a better idea how they fail (well, I suppose we could just make them more spread out...) What really annoys me is the CFL technology is 10+ years old by now, and there are still very few LAMP manufacturers that DESIGN lamps to use CFL bulbs. (or even better, spread out the electronic ballast in the lamp, and use some sort of new socket for the bulb-shaped CFL tubes. There's little doubt in my mind that the quasi-bulb shapes are a lot more esthetically pleasing than "normal" fluorescent tubes.

at 10/15/2008 1:26:43 AM, Steve Nordquist said:
CFL designs are great. I can get 5 years out of a kitchen globe by putting a gap from the fixture at tha top, but I can''t get notes on why I constructed those spacers to survive easily. I should also have changed the globe to pass UV. They ''work'' nicely in concert with the kosher lightswitches, which switch on a bit more casually--those, you know meet that ANSI 192 codicil to the lamp warrantee. Power factor at branch points has been great, and they outlast LED bulbs (esp. because of balanced A/C rather than transformer-balanced single-return branches, which let the rectifier/RC-inlet run in flyback mode in the LED lamps.... Your LED lamp design may vary.) CFLs stink in baths and bedrooms, and outdoor apps, because the harmonics of the flyback are audible in those situations in particular, you can''t get nice warming, skin-tonic IR out of a good CFL, and of course like LEDs they generally don''t know to change modes when on during the day to avoid overcurrent from filled excited states. Temperature variance can be a bother too. CFL fixtures are finally in common use, but the designs that sell easily haven''t passed the ''good'' design bar by much. Art glass shades do as told in most circumstances, thankfully. It is going to be fun designing hybrids. Maybe they''ll eject the smoking line capacitors by themselves? Meanwhile, take the jaws of life to those IR cans for down spotlights (safely....) UV for kitchen apps will need nice low-downconversion chips and lenses. Otherwise we''ll be convinced it''s in the visible range after all.

at 10/15/2008 7:18:56 AM, Bruce Mattson said:
This was an excellient article. Your research is faultlss. I applaud this article for pointing out the downside of these lamps. The mercury content of these bulbs does need to be addressed since disposal of them could be a problem, especially where ground water tables are close to the surface and contamination could occur if bulbs are not desposed of properly. Thanks again for a detailed article.

at 10/15/2008 7:26:51 AM, Brian M said:
Which congressman sponsored the legislation to ban ALL incandescent bulbs without considering the consequemces? Let's out him!

at 10/15/2008 12:38:42 PM, Mike said:
Just as with incandescents, CFL's can cause fires if not installed properly. However, CFL'c, as noted in your article, have more limitations with regard to how they can be installed in various fixtures. My comment is more about the overall energy/natural resource consumption of CFL's as compared to incandescents. First, far more components are required in the manufacturing proccess of CFL's. That depletes more natural resources and will, eventually, cause sharp increases in price. Next, CFL electronics generate harmonics and electrical noise as they employ switching power supplies. These result in the mis-operation of electronic equipment, such as CPU-based devices. Further, the harmonic content will reduce the capacity of electric utility equipment by causing additional heating of conductors and transformers. This will cause the utilities to replace equipment much sooner than nescessary; again causing price increases and the depletion of natural resources. This is, yet, another example of government taking the wrong steps without knowing all of the facts and effects of their actions.

at 10/15/2008 5:35:26 PM, JAMES TYRER said:
Well, it appears that nobody considered my first commet in the ones that followed it. Most of the issues raised can be addressed by permanently retrofitting lamps to use standard CFLs without the integral ballasts. Permanent retrofitting is changing the socket and installing a ballast. Separate ballasts are available with high powerfactors although an inductive ballast is probably adequate for residential use.

at 10/15/2008 5:48:16 PM, R squared said:
I have been using CFL's successfully for several years in the horizontal position in closed fixtures. The incandescents that had been used had very short lives. I have yet to replace a CFL, so I have no idea how long they will last. I also have two on table lamps that I have on timers as an anti burglary device and they burn for hours even though no one is there. None of my CFL's has failed yet and it has been several years. One that is in the horizontal position just passed 3 years and it is doing fine. I never had an incandescent last 6 months in that fixture.

at 10/15/2008 5:58:40 PM, WestfW said:
hi james: I've actually had worse luck with "150 W equiv" ceiling light with separate electronic ballast (30W (?) circular fluorescent bulb) than I've had with many CFLs. The ballast is not easily replaceable, and it's potted, so I can't even dissect it for parts. When it blows, I pretty much have to replace the whole fixture, which is a real PITA. I'd also think that moving the actual bulb further from the ballast circuitry would make the RF interference issue worse.

at 10/17/2008 4:55:23 AM, notohp2002 said:
I think it was 1997 that I replaced all my incandescent light bulbs with CFLs. In about 2 years I began to notice an energy savings. The CFLs used less energy but are only aboyt 1/2 the total used in a house, but the energy cost went up, which kind off doubled that CFL savings. I did find that a few lamps went bad in less than a year, but many lasted 5 years. The first try at CFLs by Sylvania was not too good, there was problems. I now have mostly 13 watt GE type which seem to be the best I have tried so far. I have even used the 13 watters in enclosed outdoor fixture {2 of them}They still last 5 eyars.

at 10/17/2008 5:44:00 AM, Dr Bob said:
While CFLs are more efficient at converting electricity to light they do not necessarily save energy. The reason - Incandescents also produce heat, take this away and you have to source this heat from elesewhere as this heat adds to your overall heating budget. Electricty costs may be higher for heat generation so there may be a cost saving using CFLs but there is no energy saving except in summer.

at 10/17/2008 10:49:12 PM, Techineer said:
A very good article comparing CFLs to other type lamps can be found at: sound.westhost.com/articles/incandescent.htm

at 10/19/2008 11:47:39 AM, Nagesh Padasala said:
Thanks for an excellant practical failure analysis on CFL. In asia power starved countries like INDIA are in a hurry to implement energy saving projects by replacing conventional filament lamps with CFL.Will they care u'r analysis? It is up to the certifying authorities to subject Life cycle test on random CFL lamps manufactured and then allow it in the market so that customers will not loose heavily by premature failures of CFL. Altrnativily CFL industry should try and evolve Higher temperature with standing electronics or thermal shielding to protect electronics to increase life time cycle on CFL. Regards P.S.Nagesh VIBGYOR ENERGY SOLUTIONS, Plot no 102,NagappaNagar, Chromepet West, Chennai-600044, TamilNadu, India Phone :91 44 22384753 E-mail :padasalanagesh@yahoo.co.in

at 10/20/2008 8:07:26 AM, CFL Fan said:
Think we should remember that the main objective of new lighting technologies is to save energy. If the net energy required to not only operate the device, but also to manufacture it is less, then perhaps the initial cost to the end user is something we should consider as an overall burden/benefit we all need to share towards the conservation of fuel sources, until new sources of energy can be effectively deployed.....

at 10/22/2008 11:43:38 AM, Chris PE said:
First of all , I am not Chris P and I don't like his comments. CFLs are not perfect , shortlasting and contain highly poisonous gas that can be released to home air. Spectrum of light contains blue , which is not the healthiest for our vision and if you look closely on most of them just like fluorescent they change color of everything.There are high quality CFLs , but they are sold only in specialty stores and they look like lightbulbs.The only difference is that they are double hermetized, so when an inside glass cracks(and it will like it does on most of CFLs) an outside baloon will keeo it contained.Otherwise , sorry ,But I will NOT replace all my bulbs with CFLs.They are good for garage,laundry room,( not bathroom because it will make you look yellow) ,hallways and outside light.Living areas should have natural light bulbs which spectrum is directed toward yellow(sun) not fluorescent (corpse pale).There is a happy medium without offending anyone and being "know everything".Use it Chris P.Be humble and learn before you post comments.Margery is a very knowledgeable engineer and she is humble in her great knowledge, which cannot be said about you Chris P.

at 10/24/2008 7:42:34 PM, cakesisbaking hotmail.com said:
if we would just have free power sources we should be able to choose our own method of lighting our bedroom. and way yea to the CFL tips and info offered here.

at 10/30/2008 11:00:04 PM, Jeannie said:
CFL's just don't last as long as they claim. I've thrown out two just within a year of putting them into ceiling fixtures, so the reports of not lasting long in "down-lighting" application surely do apply. There is something that does work very well, however, and I can't understand why they are not being used by everyone. They are little button and rubber ring devices that are used with your incandescent bulbs and they save not only electricity, but they truly extend the life of your incandescent bulbs. I have used them for at least ten years now, and somme of those bulbs are still working. The light is dimmed a little bit, but not enough to matter to me. They weren't expensive and they work!!! So why aren't we all using them? As I remember, they are supposed to change the ac current to dc which makes the bulbs last much longer. They work! They work well! Why are we being forced to deal with these expensive and polluting CFL's? Well, I would surely like to get some more of these other practical devices, but I can't remember the name. Can someone out there help?

at 11/4/2008 10:44:12 PM, Frank said:
Whatever you do, stay away from Bright Effects brands from Lowes. They're made by FEIT ELECTRIC(www.feitelectric.com) & there's tons of complaints on these: www.onebillionbulbs.com/cfl-bulbs/13297-Circuline/1923/US

at 11/5/2008 11:32:32 AM, Frank said:
This is why I NEVER want to buy a 1st year model Detroit car. In effect, you wind up playing consumer Guinea Pig, Beta group and the lessons learn for the mfgr come at your expense. Same thing here with CFLs except the learning curve seems to take alot longer to develop. I agree, they need to go slow and easy on banning incandescents, just like they should have done with phasing in of the 1.5 gal toilets. We consumers always get dragged around by uninformed experts and bureaucrats who fail to consider all the life-cycle issues.

at 11/6/2008 1:00:48 AM, Martin said:
I use CFLs in some of our pendant fittings, and in two glass shaded wall lights with the lamp inverted (tube uppermost) I have found that the CFLs in the wall lights have a shorter life than those in the pendants.This strikes me as very odd, as the report stating pendants run hotter makes perfect sense...although my glass shaded wall lights have open tops, and no vent holes in the bottom, so there can be no convection current to cool the lamp... I have also noticed that the CFLs in the wall lights lose output, and blacken quicker than those in the pendants. Any ideas for this happening? Finally, my general view on CFLs in the home situation. I have never had one last anywhere near as long as manufacturers claim, some have failed before incandescents in similar situations. They are good where you perhaps leave them on for long time periods, hallway, stairs etc, but you still can't beat an incandescent and dimmer in living rooms, bedrooms etc.

at 11/6/2008 8:34:16 PM, Not all CFLs are bad said:
I have six Panasonic EFT18LE-T 18W CFLs that I''ve been using for long hours almost every day for the past 18 years or so, with NO failures. They are still quite bright, though of I course I can''t remember how different they were when new. They run cool, and have no noticeable heat discoloration. I''ve moved several times during that period, and have run these lamps in all sorts of orientations, in a variety of fixtures. It IS possible to make good CFLs, but you can''t buy them for $1. All the ones sold by Costco are absolute crap--I''ve never gotten even a year out of them.

at 11/7/2008 8:26:47 AM, Fix for some (most?) dead CFLs said:
Somewhere I read that the component most likely to fail in a CFL is the large electrolytic capacitor, since presumably very low-quality caps have been used to save on costs. I haven't yet tried replacing the cap in a dead CFL, but it seems a worthwhile experiment. There are electrolytics available with high temperature ratings (note the ones used on premium computer motherboards), and one could replace the caps in new CFLs to make them more reliable.

at 11/14/2008 6:38:38 AM, DrewDc said:
I was an early promoter of CFLs in my home, but experience has shown me their faults. While I'm not denying their considerable benefits in energy efficiency, had I known the deficiencies of CFLs beforehand, it would have saved me a lot of trouble, time, and money over the years. One problem with CFLs is that they produce a significant amount of RFI. I use an attic TV antenna, and whenever someone is using CFL-equipped ceiling lights on the second floor, I see snow on certain channels. Second, most CFLs are not dimmable, and the ones that have dimming-capable circuitry remain too expensive for widespread use. Third, many lighting devices are incompatible with CFLs. I have an outdoor lamp equipped with a photocell, and when I replaced the incandescent bulb in it with a CFL, it fouled up my home's DSL connection.

at 11/14/2008 6:38:49 AM, DrewDc said:
I was an early promoter of CFLs in my home, but experience has shown me their faults. While I'm not denying their considerable benefits in energy efficiency, had I known the deficiencies of CFLs beforehand, it would have saved me a lot of trouble, time, and money over the years. One problem with CFLs is that they produce a significant amount of RFI. I use an attic TV antenna, and whenever someone is using CFL-equipped ceiling lights on the second floor, I see snow on certain channels. Second, most CFLs are not dimmable, and the ones that have dimming-capable circuitry remain too expensive for widespread use. Third, many lighting devices are incompatible with CFLs. I have an outdoor lamp equipped with a photocell, and when I replaced the incandescent bulb in it with a CFL, it fouled up my home's DSL connection.

at 11/14/2008 6:38:58 AM, DrewDc said:
I was an early promoter of CFLs in my home, but experience has shown me their faults. While I'm not denying their considerable benefits in energy efficiency, had I known the deficiencies of CFLs beforehand, it would have saved me a lot of trouble, time, and money over the years. One problem with CFLs is that they produce a significant amount of RFI. I use an attic TV antenna, and whenever someone is using CFL-equipped ceiling lights on the second floor, I see snow on certain channels. Second, most CFLs are not dimmable, and the ones that have dimming-capable circuitry remain too expensive for widespread use. Third, many lighting devices are incompatible with CFLs. I have an outdoor lamp equipped with a photocell, and when I replaced the incandescent bulb in it with a CFL, it fouled up my home's DSL connection.

at 11/14/2008 6:40:21 AM, DrewDc said:
I was an early promoter of CFLs in my home, but experience has shown me their faults. While I'm not denying their considerable benefits in energy efficiency, had I known the deficiencies of CFLs beforehand, it would have saved me a lot of trouble, time, and money over the years. One problem with CFLs is that they produce a significant amount of RFI. I use an attic TV antenna, and whenever someone is using CFL-equipped ceiling lights on the second floor, I see snow on certain channels. Second, most CFLs are not dimmable, and the ones that have dimming-capable circuitry remain too expensive for widespread use. Third, many lighting devices are incompatible with CFLs. I have an outdoor lamp equipped with a photocell, and when I replaced the incandescent bulb in it with a CFL, it fouled up my home's DSL connection.

at 11/21/2008 8:42:17 PM, Brinkworth said:
My opinion on all these objections on CFL are most probably due to: 1) understanding on their usage and 2) the poorly designed electronics. For confined places & places where we only need the light for short period of time, we should stick with the incandescent bulb. Secondly I think that it''s about time that they separate the electronics from the florescent tube.

at 12/1/2008 2:06:38 PM, Canada Mike said:
I use CFL everywhere at my cabin with wind and solar power. And I have about 8 failed CFL units in my junkbox. My biggest objection - for those of us up north is the energy savings claims. Consider a condo in Vancouver with 15 100 watt incandescent bulbs and baseboard electric heat. Today the temp outside is a balmy 9C, in Toronto 2C. What will be the savings for the "green" condo owner who replaces all the 100W bulbs with CFL? And unplugs all the wall wart phantom loads? And goes to an energy efficient refrigerator? And turns of their computer and DSL box after each use? The answer - for 8+ months of the year is zero savings. And in the summer months, lighting is used much less up north due to the very long days.

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