Talk:Compact fluorescent lamp/Archive 4

vs. LEDs
This is a continuation of a dicussion that began on my talk page. I changed an edit to match what the reference says--that 100 lm/W LEDs have been made in the lab--rather than to say that they are available. Another editor found some that have just become available that are are 100 lm/W, and changed the article back to claiming that they are available. That reference needs to go in the article in order to retain the claim that they are available, so I put a tag there as a placeholder for the new reference that I assume he's planning to put in. I also added a reference that lists efficacy of actual LED products that are much lower than the LEDs themselves, which is a more relevant reference point for this article, although it's useful to know that in the future LEDs could at least in principle be made competitive.Ccrrccrr (talk) 23:12, 4 January 2009 (UTC)
 * It would also be important to distingish lumens per watt of electrical input at the terminals of a practical lamp that could be sold at a hardware store in a lamp expected to last thousands of hours, vs. lumens per watt input at the junction for a diode sitting on a solid silver heatsink in a bath of liquid nitrogen that lasts for microseconds. A physics experiment is not a lighting altenative. Ligting efficacy figures must include all the ballast losses. --Wtshymanski (talk) 01:55, 5 January 2009 (UTC)
 * I extended your recent addition to include more of this, at risk of having more here than we should (should be in the solid state lighting article).Ccrrccrr (talk) 00:55, 6 January 2009 (UTC)

This is somewhat strong, a practical lamp could be made that emits over 100lm/W with LEDs. It would use the most efficient available LEDs, perhaps slightly under-run (0.7W or so each), on a modest heatsink, with a 90% efficient ballast.

However, this would not be commercially viable, as it's _lots_ cheaper if you're wanting 600lm (even if you're aiming for OK efficiency) to run the LEDs at 3W, not 0.7W, as you need 1/4 of the number of them, and the power used only goes up by 1.5* or so. And the ballast won't be 90% efficient in a realistic fixture either.

I'd ballpark a 1600lm cool white (~100W incandescant equivalent) LED lighting fixture taking 16W to drive it at ~$100 cost, neglecting profit. I've added language after the LED claim and reworded the DOE ref somewhat.

I need to find a nice citeable source for the 100lm/W figure, not a synthesis. http://www.cree.com/press/press_detail.asp?i=1227101620851 is interesting, though not relevant (prototype 160lm/W LEDs). LEDs are fun devices in some ways, but they are certainly not ready for 'ordinary light bulb' replacement yet. --Speedevil (talk) 10:14, 5 January 2009 (UTC)
 * We're not supposed to do original research here; it would be best to find examples of LED light products and manufacturer's quoted efficacy (lumens of white light vs. electrical watts input). Seoul Semiconductor was claiming a new record at 90 lumens/watt in Feb. 2008 (see for example http://www.reuters.com/article/pressRelease/idUS225604+26-Feb-2008+MW20080226 )in what looks to be something like a commercial product, not a lab experiment...but I haven't seen this incorporated into an actual product. This article should just point at the solid-state lighting article and not get too far into details - that's what links are for. --Wtshymanski (talk) 14:49, 6 January 2009 (UTC)

OR in the article - no - OR as an illustrative point on the talk page I don't see a problem with. Of course only citeable stuff should be on the article.

Having said that, what about a form of words something like: '''LEDs are dramatically increasing in efficiency, improving 5 times over the last 3(?) years. (ref luxeons first product to the current cree), and decreasing in price for given brightness. However, as of 2009, LED lighting products are typically at best as efficient as CFLs, and more expensive, though both of these may change. (ref: DOE, that link I found on 'upcoming 100lm/w' lighting solutions) For more information see LED lighting.'''

going into lumens/watt figure raises all sorts of issues, and is probably not really appropriate in here, plus something similar to the above words is shorter, which is almost always good.

--Speedevil (talk) 17:54, 7 January 2009 (UTC)

Efficacy
There is a graph that shows a significant difference between two incandescent lamps (220V and 120V) with the 120V being more efficient. The difference must be due to different manufacturers and has no theoretical significance. Only lumens/watt are meaningful comparison. Or, am I missing something? —Preceding unsigned comment added by Ck.mitra (talk • contribs) 09:53, 5 October 2009 (UTC)
 * It's well established that the efficiacy of incandescent light bulbs varies by wattage and voltage. In the 25 to 100 watt sizes used for household lighting, 120 volt incandescent lamps have higher lumens/watt than the same lamps made for 230 V. Very large lamps may be more efficient if made for 230 V instead of 120. Smaller lamps (a few watts) are more efficient if made for much lower voltages than 120 V.  --Wtshymanski (talk) 15:17, 15 October 2009 (UTC)
 * To add to the above. The efficiency of any particular lamp is a function of the temperature at which the filament is operated, the hotter the filament, the more efficient the lamp.  The operating temperature is a compromeise between high efficiency and lamp life, the higher the temperature, the shorter the life.  The life is determined by the rate at which the tungsten is 'evaporated' off the filament onto the glass bulb.  That rate is determined by the available surface area to volume ratio of the filament.
 * If we consider a 100 watt 240 volt lamp, it has an efficiency of 13 lumens/watt (or 1300 lumens for the lamp). A 100 watt 120 volt lamp has to have a quarter of the resitance.  This is accomplished by making the filament half as long and with twice the cross sectional area.  This filament has a lower surface area to volume ratio and can thuis be operated at a higher temperature for the same life.  A 120 volt 100 watt lamp thus has an efficiency of 17 lumens per watt (or 1700 lumens for the 100 watt lamp).
 * Other means of increasing the efficiency for a given life are; using a filling of a denser gas (e.g. Xenon in lieu of Argon); Using an even lower voltage construction (though the return rapidly diminishes especially in larger wattages); or using a halogen filling with a high temperature bulb (usually quartz).  Lamps with efficiencies as high as 22 lumens per watt with 4000 hour lives are readily available (though the efficiency is never advertised on the packaging).  It should be noted that a 20 watt Compact Fluorescent lamp using a 2700K (equivalent) phosphor only has a luminous efficiency of 24 lumens per watt (not the 60 lumens per watt claimed as that only applies to the 6500K equivalent phosphor). 20.133.0.13 (talk) 13:15, 21 December 2009 (UTC)
 * Low Kelvin lamps have lower efficacy than higher (bluer) lamps due to the characteristics of the eye. The people who hand out the Energy Star logo claim that any 20 watt CFL carrying that logo must produce at least 65 lumens per watt for a fixed-loutput screw-base bare lamp. This must be at the actual Kelvin CCT produced by the lamp, not at some other CCT. See table 4A, on page 6 of  which is currently cited in the article. --Wtshymanski (talk) 14:53, 21 December 2009 (UTC)
 * There are no lamps sold in Europe that have any 'Energy Star' marking. They couldn't be tested to that document anyway since it specifies a specific operating voltage and frequency which is incompatible with European lamps.  Further, the lower equivalent Kelvin phosphors really are less efficient than the higher ones in terms of real (not perceived) light energy output (due to the fact that they have to 'shift' the light frequency further).  No 20 watt lamp sold in Europe has ever claimed to have a luminous efficiency as high as 65 lumens per watt.  The standard output claim is 60 lumens per watt for a 20 watt bare standard B22 base lamp (or 1200 lumens), but this is a 'design light output'.  The commercial catalogues state (if you search the small print) that it is the user's responsibility to multiply the design light output by the efficiency of the chosen phosphor.  For a 2700K phosphor the relative efficiency is just 0.4.  This fits in pretty well with independent tests of 20 watt CFLs with 2700K equivalent phosphors (described here as 'incandescent white').  Those tests found no such lamp that exceeded 480 lumens output (or 24 lumens per watt).  The eye is less sensitive to longer wavelengths which makes it (by definition) impossible to have a lamp with longer wavelength have the same lumen output as a lamp with a wavelength nearer the peak sensitivity of the eye.  It is only the 6500K equivalent phosphor lamps that achieve anything approaching 60 lumens per watt.  Running an otherwise identical 2700K lamp together with a 6500K lamp makes it very obvious that the latter has a far higher lumen output than the former.  Indeed several perfect comparisons are visible from my desk as I type.
 * This was exhaustively documented and discussed in these very discussion pages a coule of years ago, but the discussion was quickly deleted by one of the resident environmentalists once he lost the argument. 20.133.0.13 (talk) 14:38, 22 December 2009 (UTC)
 * I wonder why a real environmentalist would argue in favor of adoption of a technology that used more resources and energy? Doesn't seem plausible. Surely the same European continent that produces standards dictating the shape of carrots has also standardized the performance of CFLs. The advantage of the American "Energy Star" program is that anyone can download the standard for free, while I suspect obtaining an equivalent IEC document costs hundreds of Swiss francs. Yes, lower color temperature white lamps have inherently lower efficacy than higher color temperature lamps, due to the response of the human eye - but if lamps sold at American hardware stores can beat 50 lumens/watt routinely, I'm sure the ones sold in Europe and the rest of the world can meet that as well.  The theoretical limit for white light is somewhere over 200 lumens/watt, so every lighting source has room for improvement - but there's no reason a whit CFL can't meet 60 lumens per watt (even with ballast loss). T8 linear lamps get up to around 100 lumens/watt (not sure if that includes ballast loss). I found that the UK has an Energy Saving Trust that labels compliant CFLs - how is this handled in your country? And again I ask, why all the fear? --Wtshymanski (talk) 14:22, 6 January 2010 (UTC)
 * At least this guy [] has done some research of his own, though it's frustrating that he doesn't go to the next logical step and run a lamp to failure. --Wtshymanski (talk) 15:37, 6 January 2010 (UTC)

Mercury Graphic Needs Updating
That data is for older CFLs, today's CFLs contain much less mercury and use less energy. The graph should be updated with the latest US DOE data which states that CFLs contain 0.4mg of mercury and release 1.2mg of mercury from electrical use over their lifetime. Versus 5.8mg of mercury used by an incandescent bulb.

http://www.energystar.gov/ia/partners/promotions/change_light/downloads/Fact_Sheet_Mercury.pdf (Pages  1-2)  —Preceding unsigned comment added by Jared999 (talk • contribs) 19:31, 16 February 2009 (UTC)

Jared999:

The graph should be indeed updated, or rather removed, as it is misleading - wrongly assuming that ALL electricity is generated by mercury-rich coal.

Also - it is easy to filter out mercury at a coal station (and some do), but hard to avoid it when you break a fluorescent bulb at home (you sould leave the room for 15 minutes to avoid inhaling the mercury vapor, according to a Sunday Times article).

I don't quite understand your numbers, they actually release more mercury than they contain?? And what about when they break?

Xmedh02 (talk) 21:48, 8 June 2009 (UTC)
 * Updated with 2008 EPA FAQ numbers, see below. --Wtshymanski (talk) 23:58, 27 December 2009 (UTC)

dangers
Some of these lightbulbs will cause housefires if connected to a dimmer switch http://www.wusa9.com/news/living_green_now/story.aspx?storyid=83615&catid=175 and because of the type of light that these lightbulbs emit, senior citizens who have had cataract replacement surgery cannot use them due to the loss of their natural eye lens. rumjal 11:09, 7 April 2009 (UTC). —Preceding unsigned comment added by Rumjal (talk • contribs)
 * One TV "news" report of ONE fire, allegedly caused by a CFL connected to a dimmer. Well, it's not much, but it's something - though I wish it was a citation to the lawsuit against the bulb manufacturer. More forensic facts would be nice - brand of lamp, brand of dimmer, location of lamp in house, etc. but that's more information than TV "news" can handle.
 * In a world where you now have to have shutters on receptacles to stop children from poking nails into them, and GFCIs built into the cords of air conditioners and hair dryers to prevent electrocutions when dropped in the tub, surely there's be a massive hue and cry against killer bulbs. Where's the Consumer Product Safety Commission announcements?
 * I don't even understand the mechanism that could start a fire. How does a CFL catch fire if *less* average voltage is applied? The first stage is a voltage doubler (in 120 V lamps) - that's why most CFLs don't dim, because the peak of a phase-controlled dimmer waveform is still the peak of the AC voltage coming in, it's only the RMS value that changes, and the voltage doubler is something of a peak-picking circuit.  I'd love to see a MythBusters-style expose of this, though it might take *years* of bulb abuse to see any failures. I've seen at least one CFL on a dimmer and it wasn't on fire, though it didn't dim properly. If the pass transistor in the inverter stays on too long, surely this just pops a thermal link like would happen at the end of life of the bulb anyway? How does this lead to a fire?
 * I don't understand the second part, either. After my cataract surgery I explicitly asked my doctor if there was any lighting situation I should avoid - though I was thinking of things like glow bowling where UV is deliberately emitted for visual effects. My doctor didn't warn me of any fluorescent lamp concerns. And there's got to be 100 million people who go to work every day under fluorescent lamps who have had lens replacements...where are the legions of the blinded? Certainly I read comfortably by the light of my bedside CFL.
 * Why all the fear? --Wtshymanski (talk) 17:08, 27 July 2009 (UTC)
 * The potential fire hazard when a CFL not designed for the purpose is used with a dimmer could come from the electronics in the CFL trying to maintain full power output to the tube and thus needing to draw much more current than normal in order to try and get the same usable power from the lower voltage output from the dimmer. Parts of the electronics in the CFL might then overheat (I'm thinking most likely the initial bridge rectifier, smoothing capacitor and/or any THD reduction circuitry that might be present). BrianDGregory (talk) 22:57, 23 December 2009 (UTC)
 * I would think it's also possible that many dimmers would not like the bridge rectifier followed by large smoothing capacitor type load a CFL is likely to present to such a dimmer and might be damaged by being connected to a CFL. Same for any situation where a semiconductor switches a lamp on or off. The unusual load might conceivably damage the semiconductor; in particular the initial surge as the smoothing capacitor charges up could be larger than the inital surge drawn by a conventional lamp bulb. BrianDGregory (talk) 22:57, 23 December 2009 (UTC)
 * potential...could...possible...might Yes, I can speculate too, but if it's a common problem, where are the papers by UL and CSA and IEEE and NEMA and all the other usual agencies that discuss the problem. There's a huge inrush on an incandescent light bulb, too - the article says 15 times rated current flows for a few cycles. For more than a year when visiting my lawyer's office I fiddled with the lamp in the reception area that had a dimmer, one incandescent and one CFL lamp - now, i wasn't watching it the whole time, but surely I'd have noticed if there had been a fire in the office (or if they'd given up replacing the light dimmer). From my observation, the CFL would not dim appreciably and instead would go out while the halogen lamp still had a dull red glow. In a world where you cannot import Kinder Surprise eggs into the US for liability reasons, surely someone in charge of protecting consumers would have investigated and published by now. --Wtshymanski (talk) 06:24, 24 December 2009 (UTC)
 * You said you didn't understand the mechanism. I explained a possible mechanism. I didn't say it was a common problem. However if your saying it's definately totally safe to operate a CFL for a long time from a much lower voltage than designed then you're being very foolish. Incidentally the one particular CFL you seem to be basing your argument on does seem to be doing as I suggested it might and drawing the much same power from the lower voltage, therefore it must be drawing a higher current. BrianDGregory (talk) 00:06, 6 January 2010 (UTC)
 * I look forward to a citation of a reliable published paper that discusses failure modes of CFLs attached to dimmers. Until then, further speculation is just that, and doesn't form a basis to advance the article. --Wtshymanski (talk) 14:08, 6 January 2010 (UTC)

This article appears pro-CFL biased
It mentions all the positive aspects of CFLs, but not the drawbacks like overheating (and dying) when installed for enclosed lighting fixtures, or inability to ignite if the temperature drops below freezing (porch lights), or the poor power factor which leads a 0.5 PF 15 watt CFL to draw 30 volt-amps versus 60 volts-amps for an incandescent. These things should be cited and added to the wiki-article. —Preceding unsigned comment added by 72.70.164.155 (talk) 14:49, 27 July 2009 (UTC)
 * It's all there, in the Design and Applications Issues section.Ccrrccrr (talk) 15:15, 27 July 2009 (UTC)
 * I think the power factor issue at least should be more prominently mentioned in the "Energy efficiency" section, as it, to certain extent, affects the claimed efficency. --193.169.48.48 (talk) 14:09, 22 December 2009 (UTC)
 * How? 20.133.0.13 (talk) 14:57, 22 December 2009 (UTC)
 * And don't forget to cite your sources here (preferably reliable ones no blogs), so we can verify the facts. --Nigelj (talk) 15:43, 22 December 2009 (UTC)
 * Replacing X kva of incandescent lamps with x/2 kva of CFLs will result in something like 1/4 the line losses, assuming they are proportional to square of current. It's going to be a long search finding reliable sources that claim CFLs are less efficient as a result. This argument gets trotted out by random contributors every few months on this article. Power factor has only a little to do with efficiency of lighting. --Wtshymanski (talk) 16:30, 22 December 2009 (UTC)
 * Yes, I see the point. While I agree it's irrelevant at the individual household level, the section starts with the savings at the national level. At that level I don't agree that it's completely irrelevant, but it is true that finding unbiased and verifiable study assessing the effects is difficult. OK, I'm withdrawing my comment, at least until I find some relevant information. --193.169.48.48 (talk) 09:05, 23 December 2009 (UTC)
 * Yeah, but, what's the source of the concern? A distribution system that was supporting an entire city with X MVA worth of incandescent lamps on Friday will certainly support X/2 MVA worth of CFLs the Monday after the great lightbulb switch. What are the "power factor" people really concerned about, since it's obviously not "extra" load on the power system? Don't forget that the household that just swapped CFLs for incandescent bulbs also has a couple of TV sets, a couple of computers and monitors, a microwave oven with a phase-controlled power supply, various thyristor-controlled appliances and power tools...household loads are non-linear anyway, and changing to CFLs helps in as much as it reduces total load.  --Wtshymanski (talk) 16:16, 23 December 2009 (UTC)
 * Hi, I'm a "power factor" person. What I'm concerned about is that with a general ban on incandescents, special-purpose lighting applications will become difficult. Every light relay will have to be oversized, every dimmer redesigned, etc. And I can't afford to wait for the industry to make consumer-grade versions of these things only to discover that they're too noisy or ugly or broken or incompetently designed or whatever. I need to continue using incandescents in my special applications while the CFL industry is catching up. For a garage, CFLs are fine, but not for studios, museums, etc. —Preceding unsigned comment added by 72.196.244.178 (talk) 20:40, 23 December 2009 (UTC)
 * Those aren't power factor issues. Again, x/2 is always smaller than x for all x - so what has to be oversized? Cite a paper listing the shortage of lighting controls that can handle CFLs. I'm not a lighting designer, but I get some trade publications and I don't see anyone complaining in print about inability to design lighting systems. Please point me at a reference that says we'll be in darkness because lighting designers can't provide a lighting design without using incandescent bulbs. The ban-the-bulb laws don't even apply to specialty lighting systems, there's so many exceptions that I bet even a left-hand thread base would be exempted.  The substitution rules as I understand them aren't aimed at freaky underwater explosion proof stage lighting but at the bread-and-butter A shaped screw-in bulbs (North America) found in household sockets - which is where most of the energy goes. And again, this isn't even the ban-the-bulb article anyway. Why all the fear ? --Wtshymanski (talk) 06:49, 24 December 2009 (UTC)

Reliability and quality
I'm a bit surprised there is no apparent mention of the generally poor reliability of the CFLs available in most retail stores. It's patent that the Chinese-manufactured CFLs incorporate poor quality components, leading to premature ballast failure. Some commentary on one of the major reasons to not use CFLs should be pr4esented.

Bigdumbdinosaur (talk) 22:56, 11 December 2009 (UTC)
 * You know what to do - cite it and write it. Surely "Consumer Reports" has reviewed 100 different CFL brands by now. Are the "Energy Star" labelled units any better? I've got a  bunch of Chinese made CFLs in the house now, but haven't run them long enough to get any failures...it's only been a couple of years. --Wtshymanski (talk) 02:05, 12 December 2009 (UTC)
 * There's some here  and they did find more expensive brands tended to die sooner but only tested a few (and the number available in NZ is not as much as in the US or EU anyway I expect). As far as I'm aware the vast majority of CFLs including those who did well in the tests are Chinese made. In fact I was under the impression it's the same in the US as well at least based on the rantings of those who think CFLs are some evil eco-conspiracy. And don't you get warranties in the US too? (Something we don't unfortunately get here) According to this 2 years  so if the CFLs are really prematurely failing, keep the receipts and take them back and perhaps the manufacturers will get their act together Nil Einne (talk) 19:46, 20 December 2009 (UTC)
 * I wonder if CFLs are made anywhere but China? Extreme elements of the carbon filament brigade are not going to be persuaded. --Wtshymanski (talk) 20:51, 20 December 2009 (UTC)

Risks of mercury from breakage
I came across which may be useful. While written for NZ, much of it would be universal as it uses reports and studies largely from outside NZ. I haven't looked into it in detail but it's intended to "provide a screening level risk characterization of mercury released from breakage of compact fluorescent lamps" Nil Einne (talk) 19:24, 20 December 2009 (UTC)
 * I had a look at it. It's pretty low key and doesn't seem to be making recommendations, aside from observing  that it's probably better to clean up a broken CFL than to let it lie. --Wtshymanski (talk) 20:51, 20 December 2009 (UTC)
 * I don't know about recommendations. I was more thinking about their analysis and evaluation of the risks which seems to be what the report is about, not specifically recommending what to do if you break a light. The current section on risk just says:
 * The amount of mercury released by one bulb can temporarily exceed U.S. federal guidelines for chronic exposure.[52][53] Chronic however, implies that the exposure continues constantly over a long period of time and the Maine DEP study noted that it remains unclear what the health risks are from short-term exposure to low levels of elemental mercury.
 * Which doesn't really say much. It also later mentions "created spikes as high as 25,000 ng/m3 in air close to the carpet, even weeks after the initial breakage" which is somewhat meaningless without any real explaination of that figure. For example, if the spike is say 2x the level you'd encounter everyday from living within 200 km of a coal power station, then that's quite different from if the level is say 100000x the chronic exposure limit recommend by many health authorites. Some explaination of the risk would be useful but it's of course not something we can do OR (as sadly seems common on these sort of things in article) on so the fact we have a source which has done some analysis is useful.
 * I'm not saying it's extremeley useful, it is based on other sources particularly the Maine one but their analysis of that might still be useful. And of course we are not simply looking for conclusions, this is an encylopaedia and while the section is shouldn't get too long, we aim to provide information, not make up peoples minds or become a how to guide on what to do if you break a light.
 * However as the source was apparently written for health authorites, it should be used with care, although that's little different from scientific papers or literature reviews (albeit this isn't peer reviewed).
 * Nil Einne (talk) 21:38, 28 April 2010 (UTC)
 * I would purely love it if someone could find a source saying something along the lines of "Sure, the mercury in a CFL is undesirable, but considering you eat your own weight in fat, sugar and sodium each year, and you're a pack a day smoker, a broken bulb here or there isn't going to shorten your life expectancy any meaningful amount.", but of course no-one is going to write such a thing in these risk-adverse days. I suspect any random cheeseburger is a bigger health hazard than a broken CFL - cry "Havoc!" and let slip the dogs of and.
 * Risks are funny things. A 1 in 30 million chance of a crib collapsing or a car acclerating creates a massive recall, whereas a 40% increase in stroke probability does not dampen the sales of salty food one bit. --Wtshymanski (talk) 21:52, 28 April 2010 (UTC)

Mercury emissions graph again
I've updated it with the July 2008 EPA fact sheet numbers, and I've probably mutilated the original in some way. Before I put it back into the article, here it is to look at. Any fixes in the next few days would be appreciated. --Wtshymanski (talk) 21:01, 20 December 2009 (UTC)
 * Looks fine, but replace the cooling tower with a smokestack (or just remove the images) because:
 * cooling towers don't emit mercury
 * not all thermal power plants need cooling towers (e.g. cogeneration plants, plants next to rivers or lakes)
 * dispel any association with nuclear power
 * If you add it to the article, mention that it only applies in the United States (the calculations use a national average for mercury emissions per power generated). Totsugeki (talk) 23:48, 20 December 2009 (UTC)
 * Thanks for updating the graph; looks great! As Totsugeki suggested, it would be a good idea to substitute a smokestack for the tower.  Seems like there should be consensus for adding it in now that it's up to date.Joren (talk) 00:49, 21 December 2009 (UTC)
 * A smokestack would be better but i'm not going to draw one - it was a struggle just updating the old image. Coal plants need cooling, too, but I agree that's not where the mercury comes out. The EPA fact sheet explains in detail the inputs to the figure, based on average US emissions of mercury per kwh over the whole of the US and the estimated emissions after landfilling a CFL. Everybody's coal plant emits mercury.  Could also mention that coal plants emit arsenic, vanadium, and other elements, aside from CO2 which might be the biggest single problem. --Wtshymanski (talk) 01:25, 21 December 2009 (UTC)
 * The Kane and Sell book I bought and have been using as a reference says (on page 193) that the average German kwh came with 0.037 mg of mercury, but that was a statistic from 1992 - I'm sure the balance has changed since then. The important thing is that emissions from landfilling lamps are small compared to what goes up the stacks. --Wtshymanski (talk) 01:32, 21 December 2009 (UTC)
 * revised again, got rid of the cooling tower, also got rid of the cfl spirals which were too small to show up now. i think it's ok. --Wtshymanski (talk) 06:30, 22 December 2009 (UTC)

Non-neutrality of article
After reading this wiki-article, I feel like running-out and buying a CFL right now. The reason I feel that way is because the article is slanted in favor of CFLs, and neglects to mention many of the known flaws of these new bulbs. That needs to be corrected. Theaveng (talk) 15:09, 4 January 2010 (UTC)
 * You'll have to identify non-neutral statements. More than half the entries of the table of contents talk about limitations and problems with CFLs. --Wtshymanski (talk) 15:20, 4 January 2010 (UTC)
 * Okay well maybe there's not a problem with the article. It was just the impression *I* got.  I felt as if I was reading a pamphlet released by NBC-GE to sell more CFLs.  But then that might also be my own personal bias, since as an electrical engineer, I consider CFLs an inferior technology.  Too many flaws (sensitivity to heat, slow to turnon, expensive, short lifespan in frequent on/off cycles, et cetera) for limited return.    Theaveng (talk) 15:28, 4 January 2010 (UTC)
 * [EDIT] I see the problem now.  This article is strictly controlled - nobody is allowed to make changes unless the change is pro-CFL biased.   Theaveng (talk) 16:21, 4 January 2010 (UTC)
 * So which statements do you think are non-neutral? The flaws are described at length. --Wtshymanski (talk) 16:39, 4 January 2010 (UTC)

I'll toss in my 2 cents... you gotta be specific about bias. We can't go on "general impression" because everyone's gonna have a "general impression" that their pet idea's been neglected. If something needs a citation, add a tag. If something's POV, come here and talk about it; use quotes so we know what you're talking about.

I agree; sometimes people have an itchy trigger finger with the reversions, and sometimes legitimate edits get thrown out in the mix. That's happened to me. I suppose it comes naturally after being subjected to lots of IP-edit spam. Just please tell us exactly what you want changed, use sources (try to find something more authoritative than blogs where possible) - and feel free to examine some of what you see as pro-CFL sources. They may not be suitable either.

(for what it's worth I guess I'm more pro-LED than anything else but that doesn't mean I gotta like some of the edits people try to pass off here)

Joren (talk) 16:54, 4 January 2010 (UTC)
 * "Pro-LED" or "Pro-CFL" makes about as much sense as being "pro-screwdriver" or "pro-hammer" - different tools for different jobs. It would be nice if arguments for or against technology X were based in reality. And it's not our job here to argue pro or anti anything, either - "Just the facts, Ma'am". It's really annoying when an edit flies screaming in the face of common sense. One should also contribute to articles without mutilating Wikipedia formatting or the English language. --Wtshymanski (talk) 17:09, 4 January 2010 (UTC)
 * That is more or less what I was trying to say. My views don't mean I have to like the edits being made here.  Joren (talk) 17:11, 4 January 2010 (UTC)

History of CFL bias
On the history of the CFL: there is a GE bias here I think. The history only reflects the account GE, which decided to not pursue the CFL. All of the big lighting manufacturers have been busy miniaturising some form of efficient lighting to come with an incandescent-lamp replacement product. GE favoured compact metal halide I think. It is a well-known and well publicised fact that Philips was first to have designed (not from leaked GE knowledge!) and marketed the CFL (the SL* depicted in the image). I will look into this later. MaartenGoWest (talk) 16:18, 27 January 2010 (UTC)
 * There's a little bit of history in the Kane and Sell book, some of which you might see in the Google Books preview. I'd like to see more history, and the GE stuff is not very well referenced either. I read (somewhere) that the spiral lamps were originally costly because they required a lot of hand labor - judging by the 6 pack selling for $9 at Canadian Tire, they must have beaten that even paying Chinese wages. --Wtshymanski (talk) 16:33, 27 January 2010 (UTC)

Design and Application Issues
I noticed a lot of the reversions seem to have been focused on this section and how it is organized. Certainly each of the bolded issues does not deserve its own heading - let's avoid cluttering up the table of contents with one- or two-sentence headings, ok?

Looking at it now, however, it seems to me that this section is too broad, covering a catch-all array of topics and a couple criticisms and controversies under the heading "design and application issues". I mean, we've got CFL-lifetime issues, safety issues, user experience issues, power issues, equivalent-incan-wattage issues, all under the same heading. Seems like we ought to be able to organize it better, but I'm not sure what to do about it. I think it could do with some refactoring under at least one or two additional headings; I didn't want to try doing it in the midst of an edit war, but at some point in the future we might consider splitting it up somehow. Any ideas?

Joren (talk) 17:37, 4 January 2010 (UTC)
 * It is a mess, and it might be feasible to have a separate article about the pitfalls of the technology. NJA (t/ c)  17:42, 4 January 2010 (UTC)
 * It would be very helpful to re-allocate some or all of this wide ranging section, strongly agree. Dimmable CFL in my opinion deserves a top level section of its own.  (MilkTheImp (talk) 15:51, 6 February 2010 (UTC))

Light Output?
There's no mention of the light output that I could see skimming the article. The bulbs grow dimmer with age being the closest. My own experience is limited, CFL's so poor that I didn't want to read by them when staying elsewhere and an electrician saying he would never install them in his own house because the light is so bad you'd damage your eyes using them. As I understand it they are sold as environmentally friendly but this is at the cost of performance, and possibly consumer eye health. I definitely won't be using them them until they get legislated as the sole saleable sort and I run out of regular bulbs. But I digress. Is there any unbiased information about their light output, especially in regards to using them as a regular reading light? 03:19, 7 January 2010 (UTC) —Preceding unsigned comment added by 203.25.1.208 (talk)
 * Sounds like subjective and anecdotal instances. CFL's get dimmer over their operating life but so do incandescents. The color balance of normal CFLs looks about the same as incandescents to me and I have never noticed any difference when using one or the other as a reading lamp. CFLs take a second to turn on and seem to get brighter over the first minute or so. Certainly testing labs have run tests of their output over their lifetime. Present ref 27 says a CFL can take 3 minutes to warm up. During that period, the color balance may be a bit different from what it settles down to, due to the different phosphors warming up. At Google Book Search, most references praise CFLs for their "greenness" in the ecological sense, but one claimed they could emit UV and that if they flicker it could produce eyestrain. Another source claimed that unshielded fluorescents emit an undesirable amount of UV and advised using approved UV filters. This may be more of a concern with conventional fluorescent tubes. Electronic ballasts in modern CFLs should eliminate the flicker seen with older electromagnetic fluorescent ballasts, since instead of the lamp going on and off at line frequency many times a second, it operated at thousands of cycles per second.  Edison (talk) 17:22, 27 January 2010 (UTC)
 * Given how toxic they are I wouldn't call them green! 118.208.169.73 (talk) 10:05, 4 April 2010 (UTC)

c.f.l
what are the name of the that is in charge of disposing c.f.l light bulbs? —Preceding unsigned comment added by 68.179.15.169 (talk) 22:10, 13 January 2010 (UTC)

Dimmable CFLs - as a section in its own right
Hi, I just added some salient new content relating to dimming, and the need for the dimmer switch to be power matched to the CFL load presented to it.

It is not easy to find the necessary information on the internet about this topic, there are as yet few outlets marketing the 'dimmable cfls' in a package with the necessary low-wattage dimmers.

This topic of dimmable CFLs in my view deserves to be set out in a section on its own, but I'm not setting out to do that, as a new poster to this topic.

Burying this in the 'issues' as a sub-heading is not in keeping with its releative importance. My contribution is not given citation as my contribution is (a) clearly the case to anyone with even a bit of background, and (b) I couldnt yet find a good citation. The experience of use of Dimmable CFLs along with dimmers designed for a minimum load of say 40W is that you soon destroy a £10 bulb after suffering an bit of severe flickering. As an aside, this will be remembered by people who share my experience of mismatched dimmers/dimmable CFLs as the pre-maturity phase for this application, like the phase where early TV sets would all too often explode or catch fire (anecdotally). Wasting £20 on two dead CFLs is my own public relations fiasco, no fires or explosions though. —Preceding unsigned comment added by MilkTheImp (talk • contribs) 15:43, 6 February 2010 (UTC) (MilkTheImp (talk) 15:45, 6 February 2010 (UTC)).

What's a ton?
Firstly, it doesn't matter, because the impact of CFLs are being compared as a percentage of other human emissions of mercury. Secondly, what units do you think the EPA meant when it said "tons" - it doesn't mean "metric tons", "shipping tons", "register tons", "air conditioning tons", "British long tons", or "wine tuns". I know Wikipedia doesn't work by common sense, but sheesh..... --Wtshymanski (talk) 04:45, 1 March 2010 (UTC)
 * While you're right it doesn't matter, it's helpful for the reader to know what units are being referred to particularly since this is an encylopaedia so we should aim for clarity and not needless confusion (after all if you replaced tons with units you'll probably find far more complaints).
 * And please remember that not everyone is an American so they may really understand or be aware of the the US's continual use of funny units and particularly if they're not use to any other ton, they may simply assume ton means the tonne and is the American spelling which is sometimes used in other countries too so is something some may have encounter (besides if the US ever gets with the program, they will be using ton to mean the tonne). And even if they were somewhat aware, they may not be aware how extensive this practice is so may not be aware or not certain that a scientific agency would continue to use such units in their public? communications. And of course even if they were aware, they couldn't be sure without checking the sources that the EPA didn't say something like metric ton but the metric past was lost at some stage in this article. And we definitely shouldn't be guessing, whoever made the change did I presume do their work properly and checked the sources to ensure they definitely did mean ton rather then guessing.
 * So it's entirely understandable that whoever it was may tag it and ask it to be clarified without wishing to waste their time to check the sources themselves because the US continues to try to confuse everyone and whoever added this in the first place did likewise (ultimately if whoever added it had bother to check the source they were using and make it clear what unit they were referring to in the first place this wouldn't be an issue).
 * Nil Einne (talk) 21:55, 28 April 2010 (UTC)
 * Hahahahahahaha, you know what's funny? When people implore others to 'use common sense' but their so called 'common sense' is completely wrong. I'm referring of course to the fact the Energy Star website explicitly says 'metric tons' so we can presume they actually mean the metric ton aka tonne and not the short ton, as this 'common sense' approach lead to. Whether they ever said ton, I don't know, archive.org doesn't appear to have this FAQ (last update was in 2008). I do know since the website says that specific FAQ was last updated "06/26/2009" it seems rather unlikely it said anything else at the time of this thread, unless they didn't properly update the last update time. Of course 'using common sense' in such a way on wikipedia is rarely a sensible idea as I've already pointed out and this example illustrates. Failing to actually check the source a worse one. Removing legitimate requests for clarification for such a poor reason an even worse one. Doing all 3, well no comment needed.
 * Nil Einne (talk) 22:28, 28 April 2010 (UTC)
 * And it seems Wtshymanski introduced the ton in the first place . Since this was in January 2009, long before the Energystar FAQ's last update, and archive.org is no use, I have no idea what the Energystar website said at the time, perhaps it really did just say tons. If so this would of course further illustrate why a 'common sense' based approach isn't sensible. If it didn't a reminder to actually clearly specify what units you're referring to, particularly when the source does and there is very obvious area for confusion even if the units don't really matter. And if you failed to, do check the source when someone points out you didn't rather then revert and argue for a 'common sense' approach. P.S. And now 3 hours later I can finally actually get to what I came here for, find out what CFL would be roughly equivalent to a 70W incandescent :-P Nil Einne (talk) 23:01, 28 April 2010 (UTC)

"Color temperature is in kelvins" Incorrect English?
Surely that should be "Color temperature is in degrees Kelvin". Or is this an US English thing? Or am I just plain wrong? (I've seen "kelvins" elsewhere on Wikipedia too) BrianDGregory (talk) 00:02, 7 March 2010 (UTC)
 * Remember that Wikipedia editors are "more Catholic than the Pope" and will use hyper-precise SI terminology that may be uncommon outside of specialist fields. You might argue that you've never heard anyone saying "kelvins" instead of "degrees kelvin", and get shot down in flames for original research by some 16-year-old basement dweller quoting the ISO announcement that henceforth the unit shall be known as "kelvins".  Have fun correcting this to what is actually used, but be prepared for a long and senseless quarrel with a monomaniac. --Wtshymanski (talk) 16:06, 7 March 2010 (UTC)
 * From my experience kelvin is far more commonly used then degrees kelvin, which isn't susprising since it's the correct usage and has been since 1968 (reasons being explained in the article). If it's true that degrees kelvin is more common in the US, I guess it says more about the state of education in the US then anything else. But I can't confirm or deny whether it really is more common in the US because my OR failed as Kelvin is a common name. I myself can't recall having read an actual reliable source use degrees kelvin before (however I don't pay enough attention that I tend to notice such errors in stupid or outdates sources), but a quick search confirmed my suspicion that there are such stupid or outdated sources. In any case, the chance you can change the correct and widely used kelvin to the incorrect and allegedly widely used degrees kelvin is slim to none. BTW the SI and ISO are largely unrelated. Also, before you say anything, I'm not 16 years old. Nil Einne (talk) 21:16, 28 April 2010 (UTC)
 * And becaue Kelvin was a real guy, and the unit named after him, his unit abbreviation has a capital letter but not the unit itself, like watts (W) but unlike lumens (lm), named after nobody. Fwiw, 16 C (celsuis or centigrade) works fine for me too. I've just been on an unsuccessful run-around to try to track down the background of the concept of the degree in units. A page needed! I have a hunch it is to do with arbitary scales of equal, conveninient subdivisions but does anyone know a solidly documented reason?  Trev M ~  15:03, 1 July 2010 (UTC)

EPA mercury emissions
Are there multiple credible reliable sources that states EPA got their figures wrong? A couple of citations can prevent many reverts. --Wtshymanski (talk) 15:44, 2 April 2010 (UTC)

Life span
The recent edits were reverted; "numerous studies" turned out to be one study and a consumer magazine report, and from what the wonky Google translation showed me, the references appeared to be making the exact opposite point from the deleted text (aside from the revelation that cheap goods aren't as good as quality goods). The Swedish link errors out so I couldn't even try Google Translate on it. If it's a real problem, there should be no trouble finding tons of English-language references that actually support the point. --Wtshymanski (talk) 15:25, 18 April 2010 (UTC)

"A 20–30% reduction"
The source quantifies the "just noticable difference" as around 2%. The article is talking about a change of 20%. How do you justify calling that "barely noticable"? – Smyth\talk 12:29, 18 July 2010 (UTC)
 * I don't care anymore.. Delete the whole article if you like. --Wtshymanski (talk) 14:00, 18 July 2010 (UTC)

Case to Ban CFL's
These are barely if any more energy efficient that incandescent bulbs if the whole life time from mfg to disposal is combined with the power factor issue, which experts (on local tv station) state cancel out the gain. Further, it is well known that CFL's do not keep up to the initial advertised rating. I have measured this on a 10 EUR top of the line 16w megaman unit, which claimed to correspond to 75w incandescent in the light output. After 6 months of use it still uses 16w but light output is closer to 40w incandescent than 75w. So you get ~25w reduction in nominal use, but factor in the things mentioned above, and the carbon emission cost of the thing due to the generators having to work harder because of the power quality issue will cancel out the carbon saving and leave us with the dozens of disadvantages listed in the article.

Power utility experts also said that because of increase in CFL use, household energy bill will be in future calculated differently to account for the power factor losses at the network, so you end up buying 10-100x more expensive lamps (at the moment) and the electricity bill will be similar to if you were using incandescent lamp after.

The disadvantages listed outweigh the advantages by a mile. And I don't think all the disadvantages are even listed, for example someone who had poor light vision told that they can't see anymore in places that have switced to CFL as the light level dropped that much. (healthy eyes can adapt better to the lower light level given time and the drop may not seem so large) — Preceding unsigned comment added by 213.243.178.205 (talk) 12:55, 14 November 2011 (UTC)
 * Citations needed. Power factor has been discussed repeatedly; most lighting has been non-incandescent for the last half century so it's not a big stretch to convert the remaining residential lighting. TV news is only good for keeping track of popular hairstyles and is notoriously inaccurate if it takes more than 15 seconds to explain an issue. EPA only gives the "Energy Star" rating to lamps that maintain light output. Generators emit less CO2 if they are producing one-third or one-quarter the amount of power that incandescent lamps would use. Utilities don't measure residential power factor because they don't care about it; it's only worthwhile to meter customers for power factor for large industrial or commercial buildings. If you use less electrical energy for lighting, your electical bill will be lower. I swapped out 360 watts of incandescents with 65 W of CFLs in my guest bathrooms and I find the light to be much improved (and I've had cataract surgery and two detached retinas). Again, I don't understand the fear; objections to use of CFLs would be more plausible if there was some science behind them. --Wtshymanski (talk) 16:43, 28 November 2011 (UTC)

Voltage of CFL

 * what is the ignition voltage for a CFL?
 * how much voltage is required for the high frequency ac current?
 * what voltage for the filament ?--Edukeralam (talk) 09:22, 23 June 2010 (UTC)

Lamp sizes
The picture would have been a little more honest if it had shown a 300 watt mogul-base incandescent next to the 85 watt CFL, and a 13-watt mini spiral next to the 60 watt incandescent. Might as well show a 4 foot long 40 watt tube, too. --Wtshymanski (talk) 00:47, 25 June 2010 (UTC)

Redundant repetition of repeated things that are unnecessary to say again
Do we actually need the section "Operation"? A CFL is just another fluorescent lamp and that article explains in mind-numbing tedious detail how the bulb works. How much of the Wikipedia do we need to recap in this article? Next we'll be explaining how the electricity gets to the bulb and how the human eye works...let's nip this in the bud. --Wtshymanski (talk) 18:36, 27 June 2010 (UTC)


 * Agree. Trimmed more basic theory from /Components/ but put link to fluorescents to say that's where info is. This is only indirectly stated once in the lead section as far as I can see, saying CFLs are a kind of flurescent lamp.  Trev M  ~  14:23, 1 July 2010 (UTC)

Brightness equivalent
Isn't it true that in reality, although the color of light from the CFL is [anemic] white, instead of the cozy yellow we are all used to, the reality is that even a higher up 42-watt CFL bulb isn't nearly as bright as a lowly 60-watt normal bulb (not to mention the 100- or 150-watt)?

This is the beauty of socialism - the governemnt FORCES us to switch, without asking what we want or leaving us our choices! Isn't it uber-hypocrytical to ban normal light bulbs, when in any metropolis there are millions upon millions of advertisement and neon lights burning 24 hours a day!

I want my bright, good old 100 watt and 150 watt incandescent light bulbs back!! --KpoT (talk) 22:45, 29 June 2010 (UTC)


 * 1) 42-watt CFL bulb isn't nearly as bright as a lowly 60-watt normal bulb' Not true. Check out lumens.
 * 2) No one's forcing you to do anything. Just search and buy them on line if you really want them.  Or fit low-voltage halogen lamps and transformers. The legislation is for those who don't really care and can't be bothered to do anything else.
 * 3) This is not a forum about lighting but a place for discussing improvements to the article.


 *  Trev M ~  13:59, 1 July 2010 (UTC)

instead of the cozy yellow we are all used to
 * More like piss yellow. And I'm used to daylight, not incandescent. Totsugeki (talk) 21:53, 4 July 2010 (UTC)


 * Brightness equivalency and comfort of light spectrum are not hand-in-hand, Comparing lumens is the best we can do now, but let's remember, best lumens come from monochromatic green light, which is by no means most comfortable to human eye.


 * What is really wrong in the article, is the bias towards official propaganda confusing people by calling electric energy just energy, Partial optimisation is one of the biggest dangers taught to engineers right after weaning off their diapers, but even higher studies in politics or economics do not seem to pay attention on wasting money in so-called savings. Example of this attitude is the table "Electrical power equivalents for differing lamps", giving impression that 60 W incandescent could be replaced by 9 W CFL with same light expectancy.


 * And last, but not least, write me, I can deliver you just about any incandescent lamp up to 150W with E27 base, even bigger with bigger E-bases ;-) They are just great for heating, and you get the light for free ;-) Of course, we will have to call it something else than light bulb, otherwise I could be sentenced for selling illegal dr... -- uups, -- goods. Seikku Kaita (talk) 12:15, 20 December 2010 (UTC)

Heating/Cooling
Can we either remove this section or explain it better?

Heat from lightbulbs contributing to heating the whole house is not cost-effective or efficient in any way. Firstly, electric heating is both more costly and more carbon-intensive than heat from most other sources, including natural gas. Secondly, the heat that is emitted from incandescent bulbs is not in the right place; it is concentrated around the bulb itself, heating the ceiling and the air above people's heads, neither of which is particularly useful.

I will remove in the near future if no objections. —Preceding unsigned comment added by Stanlavisbad (talk • contribs) 17:58, 11 September 2010 (UTC)


 * No, don't just remove it. Try to improve it. It has been through many iterations, and was considerably longer in the past with all the points you make clearly laid out. (I can find a version link for this if you are interested). Someone came along and said that that was too much detail and cut it right down. Now you say it not detailed enough and so you want to remove it altogether. If you do, someone will bring it all up again and it will have to be rewritten to clear up their confusions. One point to note is that many people do use electric heating these days, so that can't be discounted too. --Nigelj (talk) 18:31, 11 September 2010 (UTC)
 * Could we in the name of sweet reason please get *citations* before whaling on this part of the article? Sounds like OR to me; heat is heat, and if you keep the layer of air next to the ceiling warm, is it not possible that this reduces heat transfer from every other layer below it? But *I* don't have a citation for this and we all agree Wikipedia doesn't work on common sense (see above). --Wtshymanski (talk) 05:12, 3 October 2010 (UTC)


 * added more info on this. The section as it read was not very clear, it implied there was always a positive impact on energy use even when that has shown to be false were colder climates and older heating technologies exist (such as oil furnaces). Info added is also well cited. 207.81.141.208 (talk) 05:44, 3 October 2010 (UTC)
 * Can anyone find the BC hydro study? Journalists are notoriously innumerate, though I like to think the CBC can get the facts right.  It sounds peculiar to me; if you're relying on electric lights for a significant fraction of your home heating because it's cheaper than oil, why aren't you heating your home entirely with electricity? Most places *burn* fossil fuels to *make* electricity at no better than 50% efficiency, whereas burning fuel in your home heating system is at least 60% efficient; true, an electrical utility pays less per million BTU of coal than the householder pays per million BTU of natural gas. BC Hydro must be considering that most of their electricity comes from hydroelectric power, whereas home heating is natural gas. 45000 tons per year spread over a couple million houses isn't a lot, though, and I'd sure like to see the BC Hydro study. --Wtshymanski (talk) 16:10, 3 October 2010 (UTC)


 * Many Canadian's still reply on oil burning home heating. Additionally, many homes are equiped with older technology natural gas furnaces which, depending on age, maintenance and installation (or quality there of) can render a less than 60% efficiency. I'll see if I can dig up the original study for your review. 206.108.31.34 (talk) 15:44, 4 October 2010 (UTC)


 * Every 3rd house in Finland is heated with either direct or charging electric heating. Many of these houses have bedrooms upstairs, especially all the older houses, and any bigger houses. The climate is such that at leat 10 months of the year you use some energy to heating. During the one or two months when you do not need heating, sunset occurs after 10PM, if at all. Any of the claims against using classic bulbs downstairs are just void. Not to mention, every 3rd consumed kWh of electricity in Finland is free of CO2 or quick silver.


 * Comment on "heat is heat, and if you keep the layer of air next to the ceiling warm, is it not possible that this reduces heat transfer from every other layer below it?" :
 * Question is not about where the heath is produced, but where does it go? It cannot just vanish, it must go somewhere. If it cannot go through the ceiling, it must come down. Ever heard about heath radiators in ceiling? This warm ceiling talk reminds me about Good Ol' English Central Heating, where heaters are in the middle of the house (since it is against the English reason to warm the cold air by the windows) and heath pipes go outside the buiding (so they are easy to melt when, not if, they freeze).


 * There is one claim I'd challenge: CFLs could unload cooling AND save energy in 'energy efficiency savings' -- first you save the energy by not heating, then you save the same energy again by not cooling it. Doesn't this sound like counting the same energy twice?


 * These thoughts are here to calm down the heath of blood for those willing to bias the article towards the advert of Energy Saving Lamps. Seikku Kaita (talk) 12:51, 20 December 2010 (UTC)

X ray picture value
Undeniable high marks for coolness, but is it of value to the article reader? You have to zoom in quite carefully to see the broken filament, and I suspect anyone who knows where to look for the filaments anyway is not going to learn anything from the X-ray that wouldn't be better demonstrated by visible light photographs instead. Keep or remove? --Wtshymanski (talk) 05:02, 3 October 2010 (UTC)
 * In this particular case, wouldn't the broken filament be hidden by the opaque phosphor coating inside the tube? The X-ray view also shows components on the ballast board packed into the base. Component count correlates with reliability. Appropriately placed and worth keeping, IMO. __ Just plain Bill (talk) 01:41, 8 October 2010 (UTC)
 * Well, yes, but don't most things stop working when they are broken? And the component count is better illustrated by the visible-light photos of the ballast. Plus, I had to zoom in about 25X to see the breamk in the filament and I knew where to look. If I put my non-expert glasses on, all I see in the X-ray is shadowy grey squares, not components...but the visible light pictures I can relate to the insid of a TV or other consumer electronics. --Wtshymanski (talk) 13:57, 8 October 2010 (UTC)
 * The advantage of the X-ray view is that it shows everything in situ instead of disassembled and spread out. It gives a visual sense of the level of complexity involved. I see the filament break as a side issue to that. As soon as the complete image was on screen, there it was plain to see&mdash; didn't seem like excessive zoom was needed. I don't see the image as detracting from the article; is there a reason to get rid of it? __ Just plain Bill (talk) 15:13, 8 October 2010 (UTC)

energy saving light ? Says Who?
The first sentence indicates that the term "energy saving light" is specific to CFL's which I challenge. I have searched extensively and only found manufacturers using this term to help with driving sales and overall image of CFL's. I believe this should be removed until it can be well cited from 3rd party sources that CFL's are in fact "also known as". 206.108.31.35 (talk) 19:30, 7 October 2010 (UTC)
 * Did your extensive search include 15 seconds with Google Books? There were 400+ hits there when I looked, many of which refer to CFLs. I don't think you need to remove the phrase. --Wtshymanski (talk)
 * The phrase I often hear (and use) (in the UK) is 'low-energy light bulbs'. That gets lots of Google hits too. I wonder if these two have become more common in everyday use than some of the others we mention in the top sentence, especially 'compact fluorescent light' and 'compact fluorescent tube'. --Nigelj (talk) 22:08, 7 October 2010 (UTC)
 * Actually I tend to agree that CFL are no "energy saving light". They just use less energy input for the same amount of light output compared to incandescent light bulbs. Smells salespitch all the way. Comparision examples here. Electron9 (talk) 00:45, 8 October 2010 (UTC)


 * This seems to be mostly a marketing term used by manufacturers and a few enviro zealots. The term is widespread but is not exclusive to CFLs and even within google books there looks to be no specific correlation to CFL with the term being applied to LED and other technologies. It stinks of bias IMO. 207.81.141.208 (talk) 22:47, 19 October 2010 (UTC)


 * Says who? Says lots of people, but the question should be Why? Salesmen...
 * I have a constructive suggestion: replace the "or" before the "energy saving light" with "often advertised as". The British are once again better out with this, not claiming general saving of energy. The CFL itself saves no energy, it consumes more energy to make one, it makes comparative amount of light with less electric energy, or it makes more light with same amount of electric energy, compared to a traditional lamp. It may even cause additional energy consumption under certain conditions, but the CFL itself does not save energy. Anyone telling me CFL is the energy saving lamp goes to categories like "speed kills" and "http://www.dhmo.org/".
 * If just the people would say "The lamp that saves electric energy" or "electricity saving lamp" I would not complain that much.
 * "Save Electricity, burn the Rainforests Instead!" Seikku Kaita (talk) 13:35, 20 December 2010 (UTC)

More archiving
Moved some threads that haven't been active in months to Archive 4. If you're curious about something covered or not covered in this article, check out the talk page archives and see what's gone before. --Wtshymanski (talk) 20:46, 13 October 2010 (UTC)

Durablility new section
CFL bulbs are more durable against shaking and, similar to rough service bulbs found in trouble lights.


 * This could be the correct place for any statistics about actual burning hours vs promised life of CFLs, or information about decay due to cold or hot environment. Seikku Kaita (talk) 13:39, 20 December 2010 (UTC)

Basically we need to know about the maintenance factor of a CFL so that we can get an idea of the actual life rather than the one written on the lamps while its sale. — Preceding unsigned comment added by 125.22.54.142 (talk) 09:58, 10 June 2011 (UTC)

Recycling versus Broken Lamps
The subsection of this page entitled Broken and discarded lamps discusses the problems involved with broken lamps. It mentions that instructions for dealing with this problem are not always printed on the lamp packaging. It discusses the mercury problems when a lamp is broken, and how long these problems remain if the fragments are in a carpet. It talks about the meaning of "chronic exposure" to mercury.

This subsection began with a Main tag that stated: Main article:Fluorescent lamp recycling

However, the Fluorescent lamp recycling article does not address any of these issues. In this entire article, the only reference to broken bulbs in a household is the single sentence "A broken fluorescent tube will release its mercury content." It says nothing about the safety issue, the carpet issue, how long the mercury remains, etc.

Therefore it is wrong to tell the reader that the "main article" about Broken and discarded lamps is Fluorescent lamp recycling. That's why I removed the tag. &mdash; Lawrence King ( talk ) 18:38, 11 November 2010 (UTC)


 * Rather than removing it, it is relevant, so why not change it from 'Main' to 'See also'? --Nigelj (talk) 18:56, 11 November 2010 (UTC)


 * Done. Thanks!  I feel silly for not thinking of that. &mdash; Lawrence King ( talk ) 19:05, 11 November 2010 (UTC)

Hybrid CFL
Web searching only turns up the GE press release and the usual sage journalistic commentary on said press release. There's no product yet. Suggest we hold off adding it to the article at least till it hits store shelves. --Wtshymanski (talk) 01:32, 20 November 2010 (UTC)
 * Wtshymanski is right. Even though i have no idea how can we confirm this, we must mention that product didnt hit stores yet(?). GE's product also added. There are at least actual photos of that product, where wikipedians can refer to. —Preceding unsigned comment added by 79.167.42.139 (talk) 03:27, 20 November 2010 (UTC)


 * There are other hybrids than the yet-to-come GE. In Finland, you can find for example hybrids of CFL with LED already. This, of course, is a solution to a different problem than the GE will-be hybrid, but it is a hybrid, anyway. And this is a true electricity saver hybrid, LED is a real low power light source. Seikku Kaita (talk) 14:44, 20 December 2010 (UTC)

Power factor of CFLs and impact on supply-side power generation
Despite citing numerous neutral, third-party, non-commercial scientific sources from Europe, Canada and the U.S., all edits mentioning the CFL power factor debate have been removed post-haste. The issue of low power factor CFLs is much more relevant to the anti-CFL argument than the mercury issue (which tends to be over-blown). I strongly encourage open and honest debate about the power factor issue, and question which sources might pass your personal litmus test for inclusion in the article. Prguy72 (talk) 17:25, 8 December 2010 (UTC)
 * There are about 400 editors with two or more contributions to this article. I must have missed the numerous citations, all I found was a  worthless blog - so I pulled the whole paragraph.  The power factor item comes up every time a new editor discovers this article - take a look at the archives, this has been discussed at length.  It would be nice to have a valid, accessible, authoritative, reliable citation in case anything new has come up since 1994 which is when most of the interest at IEEE publications seems to have petered out in assessing the "impact" of CFL power factor on the distribution system. How many megawatts of *regular* flurorescents and halide lamps and other discharge lamps do you suppose are already being supported by the distribution system? This isn't the forum for debate...there's blogs for that. --Wtshymanski (talk) 17:49, 8 December 2010 (UTC)
 * And then there's the power factor of every other piece of electronic equipment that runs internally on something other than mains AC and so has a PSU - computers, TVs, satellite and TV set-top receivers, every kind of battery charger, stereos, hi-fi. Everything that has an electric motor in it - electric drills, saws, lawnmowers, food mixers, pumps, fans... etc etc. If people wanted to campaign against the use of all of these things, then they would have some credibility. But then they would lose it again as soon as someone did the sums. --Nigelj (talk) 10:12, 9 December 2010 (UTC)
 * Most of the world's electric lumens have been provided by some kind of discharge lighting since, oh, about 1950 or so. And what the carbon-filament brigade never explains to me is why replacing X MW of hotwires with X/3 MW of CFLs at 0.5 pf, reducing current by 33%, is somehow going to overload the system. Aside from kettles, frying pans, and the like, what household appliances actually still have 1.0 pf? And people who natter about the 4x-5x inrush of CFLs seem unfamiliar with the 15x inrush of tungsten filaments - you have to get specially rated contactors to switch tungsten lighting loads. Again, a citation to a paper that describes the changing nature of domestic loads would be of interest, but is beside the point in this article. --Wtshymanski (talk) 14:15, 9 December 2010 (UTC)
 * Of course! Street lights, fluorescent tubes in factories, warehouses, supermarkets etc. Yet it is a surprisingly consistent line of attack here. Someone somewhere must be driving it: publishing stuff that most people don't understand about W vs VA, pf, phase angle etc and blowing it out of proportion specifically against CFLs. It's mostly conspiracy-theory internet and blog noise, but someone somewhere is knowingly feeding it, I'm sure. Some actual published figures from the power industry would be interesting, but as usual this isn't them. --Nigelj (talk) 17:47, 9 December 2010 (UTC)
 * Minions of the carbon filament cartel? Those bamboo growers are powerful and ruthless and will stop at nothing in their attempts to regain control of the light-bulb industry. --Wtshymanski (talk) 18:55, 9 December 2010 (UTC)
 * They've got very sharp machetes and they know how to use them. We'd better say no more, if we want to sip our cocktails safely after sunset (on our CFL-lit verandahs), I think. --Nigelj (talk) 18:56, 15 December 2010 (UTC)

Mercury. Again.
EPA used the average emission of mercury per kwh in the US, not just coal plants, which would be higher. Let's have some perspective on quoting non-bulb-related studies of mercury poisioning till we hear of some authority banning or regulating CFLs because of it. --Wtshymanski (talk) 19:11, 9 December 2010 (UTC)
 * Environmental Engineering, 5th edition,Wiley 2003 978-0-471-41813-9 says that an acceptable daily intake of 0.03 mg of mercury for a 70 kg adult male human would provide a safety factor of 10 over the recommended levels of metallic mercury in food and water. Hmmm. 5 milligrams of mercury divided by 0.03 mg/day is 166 days. Does this mean you could eat two CFL bulbs a year and still stay below the toxic threshold?  Probably not, unless CFLs were the only source of mercury in your diet.  Makes you think, though.  Oh, and the book says that the "half life" of mercury in humans is about 74 days. --Wtshymanski (talk) 22:20, 9 December 2010 (UTC)
 * Qualified. Pregnant females and children shouldn't eat so much mercury. --Wtshymanski (talk) 04:11, 10 December 2010 (UTC)

The graph shows 14% of mercury in the bulbs escaping to the environment right? Where does the other 86% go? This whole section seems sketchy, while trying to tell us that CFL effectively reduce mercury release into the environment. How much mercury is left at he bulb plant, and how much escapes into the environment from there? The EPA put out data for the US, but if bulbs are made overseas what about the mercury back at the factory and its effect on the environment. Point is, too many question left unanswered to prove a net positive effect on the environment by the use of CFL. -- T HE F OUNDERS I NTENT  PRAISE 14:20, 23 March 2011 (UTC)
 * I look forward to a citation of a reliable criticism of the EPA numbers. The reference says that the mercury that doesn't escape to the air stays in the landfill site. --Wtshymanski (talk) 14:59, 23 March 2011 (UTC)
 * Once again, take up concerns with mercury emissions displacement with EPA, not with this article; if we're going to raise the mercury boogeyman here, we must also give "fair and balanced" coverage to what EPA says about mercury. --Wtshymanski (talk) 13:28, 12 April 2012 (UTC)

Frequently switched lights
I see little mention of the problem of frequently switched lights-- it appears to be discussed only with regard to cold cathode fluorescent lamps, where it is noted that CCFLs stand up to frequent switching better than conventional CFLs, which may have their life-spans substantially reduced by frequent switching. I have also heard that, during startup, CFLs actually draw more power than an incandescent bulb of the same light output.

This leaves me wondering, when replacing an incandescent bulb with a CFL in a location where the light is typically on for a short time (bathrooms, closets, hallways) whether it is possible that energy will be wasted, rather than saved. Do we need to pay more attention to this issue, and recommend that CCFLs or even incandescent bulbs be used in such locations? Does anyone know how short a typical use has to be before a non-CFL should be considered? -- Mwanner | Talk 20:30, 1 January 2011 (UTC)
 * It's not energy so much as lamp life; every fluorescent lamp start is a glow discharge that sputters a little active material off the cathodes. I haven't seen any documentation on this. The life problem is mentioned in the article. --Wtshymanski (talk) 00:00, 2 January 2011 (UTC)


 * Information on the considerable shortening of lamp life due to frequent switching (along with information on the extent to which they dim as they age) has frequently been edited into the article, along with reputable citations (including no less an institution than the Underwriter's Laboratory). Any edit is short lived and quickly removed (presumably by the resident environmentalists who are determined to leverage a change to CFL type bulbs when they are, in reality, far from the most environmentlally friendly solution). 86.145.136.160 (talk) 17:52, 29 August 2012 (UTC)

so irresponsible to advocate and encourage mercury containing light bulbs
The mercury content is rarely, if ever, disclosed on the packaging of these types of bulbs,and that is outrageous. They really should have a big giant mercury warning sticker on them in fact. The fact that it doesnt is very curious indeed.Thats all the world needs now is a new source of rampant mercury poisoning. Could it be industries like coal burning power plants and others, are trying to push these bulbs so they can easily SELL their waste products(e.g. their mercury)?! The article needs to discuss other alternatives to cfl bulbs, especially LED lamps/bulbs, which are safer and as effective(and almost unbreakable.)

Also there needs to be an update about how California is taking steps to ban standard light bulbs in favor of these bulbs. — Preceding unsigned comment added by Gawdsmak (talk • contribs) 08:02, 24 January 2011 (UTC)
 * See above. The amount of mercury in a CFL is less than in the average set of dental fillings.  Don't know what the bulb packages say in your part of the world (the world is a very big place), but on packages in my local stores there's an "Hg" symbol, and a warning that the State of California knows there's mercury in them thar bulbs. The mercury from coal plants isn't shipped out in bottles, but instead is vaporized throughout the local biosphere.  And if every fluorescent, HID, halide and  sodium lamp in North America all broke in the next 15 minutes, that's still less total mercury emission than ONE smelter at Flin Flon used to emit every year. You want to deal with conspiracies against our health, rip into cheeseburgers or tobacco, which are killing more people than mercury. Why all the fear?  --Wtshymanski (talk) 18:02, 27 January 2011 (UTC)


 * Average amount of mercury in human bodies at cremation in UK is 3g, mostly from mercury amalgam fillings (although much of this has migrated out of the fillings and resets harmlessly in other parts of the body). Average amount of mercury in a 60W equivalent CFL is down to 3mg nowadays. Thus you (on average) have the same amount of mercury in your body as there is in 1000 CFLs. Hope that puts things into perspective.
 * 81.187.162.109 (talk) 10:43, 4 March 2012 (UTC)

Early burnouts?
I've never had trouble with CFLs, but I've heard people say that their's have burned out early. There's a long discussion over at this "Bad Light Bulbs" blog post. One anonymous commenter hypothesizes that this could be due to spikes from the utility. Has there been much research into this? That is, has there been testing of a wide variety of brands and under a wide variety of real-world conditions rather than solely laboratory testing? I looked around but couldn't find much - Google Scholar shows an article from O'Rourke & Figueiro 2001 (Long-term performance of screwbase compact fluorescent lamps) which says at the end of the discussion section:"Post-mortem analyses were conducted to determine whether the lamp or the ballast had caused the system failure. After the system had failed, the test lamp was connected to a new ballast and the test ballast was connected with a new lamp. This procedure allowed determination of the failed component. In general, early system failures were caused by ballast failures. The majority of the system failures, however, were due to lamp failure." The above is a preprint, and this was apparently published in the Journal of the Illuminating Engineering Society (website doesn't go back to 2001). Google Scholar shows 7 articles citing O'Rourke & Figueiro, but it's not clear that they add much to the question. II | (t - c) 18:52, 15 February 2011 (UTC)
 * An anecdote: it happens. I use a clip-on bell reflector lamp as a worklight over the stationary belt sander. A few days ago the coiled CFL failed promptly when I switched on the sander and the dust-collecting shop-vac. Naturally all three units are supplied by the same 120V 15A breaker, so the lamp sees whatever induction spikes (or commutator spikes, in the case of the shop-vac) those motors put out. Came here to see if such a thing was known, and now this... thanks for bringing it up. __ Just plain Bill (talk) 23:40, 15 February 2011 (UTC)


 * I suppose this is covered to some extent at Compact_fluorescent_lamp, although it doesn't really talk about ballast failures. If you feel up for it, maybe including more would be nice - I think you might have more understanding of this than myself. II  | (t - c) 01:34, 9 March 2011 (UTC)

The PCB of the retrofit CFL
The details of the PCB is required as to how the ballast of the CFL works along with its circuit diagram. — Preceding unsigned comment added by 124.124.10.106 (talk) 09:54, 10 June 2011 (UTC)

2010 EPA vs 2008 EPA
Now EPA is saying 1.6 and 5.5 mg instead of 1.8 and 5.8 mg, still 3:1 ratio. Does anynoe think the bar chart needs updating for a visually unimportant difference? Does anyone have a reference saying EPA has missed the boat here and that CFLs in the wild on average only last 1/3 as long as EPA believes? --Wtshymanski (talk) 14:55, 29 June 2011 (UTC)

Alleged availability of recycling facilities
The last sentence of the second paragraph says "in the US many home improvement stores accept CFLs for recycling". Also, the last sentence of the first paragraph of subsection 7.3.2 (Broken and discarded lamps) says "In the U.S., The Home Depot is the first retailer to make CFL recycling options widely available". In the last two years, I have visited nine home improvement stores &mdash; four Home Depot, two Lowe's, and three mom-and-pops &mdash; and not one of them recycles CFLs. Government lists of participating recyclers near me have also completely disappointed me. I still have a few CFLs at (premature)-end-of-life that I want to recycle. I haven't yet found any research about the true participation of alleged recyclers; has anyone else done so? -JohnAlbertRigali (talk) 04:11, 15 July 2011 (UTC)
 * On the other hand, my local Rona and Home Depot both have bulb bins (though they won't take my old 4 foot tubes). We need a citation saying how many bulb bins are actually available. Did you ask your retailers why they don't have a bulb bin? --Wtshymanski (talk) 14:02, 15 July 2011 (UTC)

US centric
This article is severely lacking in data concerning contries other than the US. — Preceding unsigned comment added by 89.240.155.85 (talk) 15:48, 1 September 2011 (UTC)

How about an honest graph, instead of a biased advocacy graph ?
This is the Wikipedia entry for "Compact fluorescent lamp", not some sales pitch for CFL's (or is it?) Specifically, a bar graph labeled: "CFL" vs. "Incandescent", with a title of "Mercury Emissions by Light Source" should show the emissions comparison between the "CFL" and the "Incandescent" BULBS THEMSELVES, not the estimated emissions of some power plant a hundred miles away, under the assumption that everyone switches over, etc. etc. etc. This is ridiculous advocacy here. It's far from encyclopedic. Either change the TITLE of the graph to "the case for CFLs based on POWERPLANT emissions" or show an honest graph that doesn't put the powerplant qualifier in the fine print. An actual honest bar graph showing "Mercury Emissions by LIGHT SOURCE" in the CFL entry should show a big fat ZERO next to Incandescent. And if we are including emissions from everywhere, lets include the emissions from the CFL bulb factories and their suppliers too. 71.190.3.50 (talk) 05:02, 6 September 2011 (UTC)


 * Take it up with the EPA. If you can find a published graph, cite it. Yeah, everyone knows the bulb doesn't give off mercury while its intact. Only a Wikieditor would not get that point. --Wtshymanski (talk) 14:07, 6 September 2011 (UTC)


 * There is a strong incentive from government and environmental organizations to make people believe that CFL is a better alternative than incandescent light bulbs. Despite being a mercury hazard, having sloppy tolerances and quality in the electronic driver, producing potentially long term harmful blue-UV content etc.. Claims on mercury reduction only works when it reduces coal usage and when counting the ecosystem as a whole, lamp life claims only hold true when electronics will hold as long as the lamp itself, and other health problems won't increase the total cost.Electron9 (talk) 22:54, 14 October 2011 (UTC)


 * Well, yes, that's the point. As long as cheeseburgers are legal, there are much bigger health and environmental threats out there than CFL lamps. (A study comparing the incremental impacts of a single cheesburger vs a single CFL would be interesting.) If all of that could be documented from reliable sources, it would be an interesting comparison for the article. Is there any documentation?  Studies? Or have the government mind-control lasers gotten to all of the researchers? --Wtshymanski (talk) 17:33, 15 October 2011 (UTC)


 * Junkfood impact the health of those that eat it. Not other people. The relevance of CFL vs burger-poisoning is irrelevant to the scope. CFL-mercury vs coal fired mercury isn't. And yeah some governments push the dogma that CFL is all good. They are useful in some applications, in others that are a long term hazard. Electron9 (talk) 18:30, 15 October 2011 (UTC)
 * Well, if you generalize, you can consider impacts aside from that on the consumer. Monoculture of grains, industrial agriculture, hormone-injected feeder lots contaminating water tables, CO2 emitted in hauling beef thousands of miles to the consumer, etc. etc. - but without any numbers, it's all bar-room gossip. --Wtshymanski (talk) 20:53, 15 October 2011 (UTC)

Greenhouse Gas emissions
An edit pertaining to GHG emissions effects of CFLs was recently undone. This article is grossly misleading in that it suggests that burning natural gas for heat generates more GHG emissions than allowing incandescent lights to provide heat. Even ignoring the issue of transmission and generation inefficiency, the simple question that determines whether this is true is this: If I save one watt-hour of electrical power consumption, what energy source does that watt-hour come from? In most cases in North America this still ends up being hydrocarbon-based (coal, oil, or best-case, gas) generation. The only valid claim at that point is that local emissions, i.e. within a particular city, can be reduced. However, statements along the lines of "total greenhouse gas emissions [being reduced]" are grossly incorrect. Without sufficient research (I haven't found any cited here), the safe, valid claim to make is something along the lines of "while incandescent lights themselves produce zero GHG emissions when heating a home, and natural gas heat does, whether a net increase or decrease of GHG emissions occurs depends upon the source of the increased electrical power demanded by the incandescent light". Clearly, in the case of nuclear power, we have a net win. In other cases the picture is much more complex, and one cannot draw conclusion that overlook that fact. --Indigophox (talk) 02:19, 3 November 2011 (UTC)
 * I don't understand. If you want heat, burn natural gas in the local furnace, not at a power plant; even the best combined-cycle natural-gas-fired plant burns 2 units of gas energy for 1 unit delivered to the customer. Heating with hydro or nuclear electricity only reduces overall CO2 emissions if there's no other market for the hydropower or nuclear power; our local utility tells us to plug in CFLs so North Dakota doesn't have to burn so much coal. --Wtshymanski (talk) 14:57, 3 November 2011 (UTC)
 * That's exactly my point: Generally speaking, utilities try to use all of their nuclear and hydro capacity FIRST because it's the cleanest (and hydro, once the capacity there, is the cheapest).  So, consume an extra kWh to generate heat with a less efficient power, and in most cases 100% of that (or close) is going to be coal, or best-case, gas, which as you've pointed out is still substantially less efficient than simply extracting energy from the gas in a 95-97% efficient furnace.  However, someone felt the need to undo an edit pointing out the fact that, despite an IEEE journal article cited there, the net GHG emission impact of replacing a CFL with an incandescent bulb, during heating season, is still to increase GHG emissions simply because of where that extra generation capacity is drawn from. --Indigophox (talk) 21:26, 5 November 2011 (UTC)

Using CFLs in direct current (DC) lighting circuits
We use standard 23W (100W replacement) CFLs in our emergency lighting system at work, which is a DC circuit. Are there differences between AC and DC lamps?
 * Cool - can you point us at a citation for this? What voltage is the DC system? Does it work with any brand of CFL?  SOme types I've seen have a voltage doubler stage as input, meaning that they won't work on 125 VDC. --Wtshymanski (talk) 19:07, 30 November 2011 (UTC)


 * European CFLs (220-240 volt) just have a rectifier as the input stage. They will therefore work off DC.  In theory, the DC voltage should be around 300 volts to run such a lamp properly, but they apparently wotk quite happily of 200 odd volts.  You are correct that the 120 volt devices with a voltage doubler input will not work from DC.  London Underground, a few years ago replaced all their incandescent emergency tunnel lights with standard (UK 240 volt) compact fluorescent lamps which operate quite satisfactorily from the 200 volt DC emergency lighting supply. 86.145.136.160 (talk) 17:44, 29 August 2012 (UTC)
 * Now that I think about it, it's a little surprising that a second electolytic cap is cheaper than two more diodes (and maybe a few turns on the transformer). The reason for the voltage doubler on 120 V lamps would be good to know. --Wtshymanski (talk) 16:08, 5 December 2012 (UTC)
 * One would imagine that it would be easy to design a CFL with a simple rectifier input stage to operate from 120 volts. The only reason that I can think of is that by using a voltage doubler, it allows the manufacturer to use the same design and components downstream of the reservoir capacitor(s).  DieSwartzPunkt (talk) 18:07, 5 December 2012 (UTC)

CFLs as strong sources of ultrasonic noise
I've used an "ultrasound diagnostic tool" (normally used to detect leaks in air conditioning lines or vacuum lines) to listen to various household noises and I find that compact florescent lights are the strongest source of ultrasound in my house. This tool is not a scientific instrument that measures decibel levels, but it does present ultrasounds as audible sounds. I can stand several feet away from a wall and detect noise from a compact florescent light on the otherside of the wall. I don't think the device is inadvertently responding to electromagnetic radiation since I can put my hand in front of the device and effectively block the sound. It would be interesting to know if the ultrasonic emissions of CFLs have been quantified.

Tashiro (talk) 01:49, 4 December 2011 (UTC)

Museum conservation
Actually, just about *everything* damages artifacts in museums; it's a wonder they let them be displayed at all. Re-phrased the UV section to something like what I've seen in a few Google Books hits. They seem to be more worried about daylight than artificial light. Museum curators also worry about heat, so they don't embrace incandescents unconditionally either. Even just plain visible light still affects some items badly (and that's why, children, Grandma's old photo albums look so crummy). --Wtshymanski (talk) 15:32, 21 December 2011 (UTC)

Health effects...
"The cost effectiveness of battery-powered CFLs allows aid agencies to support initiatives to replace kerosene lamps, whose fumes cause chronic lung disorders in typical homes and workplaces in developing nations."
 * This seems little more than an advert for Sunlabob Ltd. I don't see any mention in the provided sources about how it were CFLs that made this possible. Battery powered fluorescent lamps are hardly a new invention, the fluorescent tube was invented more than 60 years ago. If anything, LEDs, not fragile glass bulbs, would be the logical choice for lanterns that have to be transported to and from the charging station. Would be cheaper as well, no need for the electronics that are used for ballast or voltage conversion and a much longer life.
 * And why you'd need a "village energy committee", a "village technician", "energy service management", "management software for data handling" and a rental system for 50 4-Watt rechargeable lamps?? Judging from the pictures I've seen, a few hundred led lamps with individual solar cells would be cheaper than the hardware for the charging station alone. Not surprisingly, one of the "risks" they mention in the folder is: "Villagers compare RE prices with grid prices".
 * I guess with their energy committees and the other bells and whistles people may not notice that all they got is a ridiculously expensive flashlight. Well, that, and also:
 * "extension of the number of working hours"
 * "Providing the opportunity to enter the carbon markets" What's one tCO2e worth,somewhere between 5$ and 50$? And they "save" one tCO2e for every half million hours they use the lamp...
 * I know, WP:OR... Ssscienccce (talk) 13:31, 11 April 2012 (UTC)
 * Well...they do use 30 or 40 litres of kerosene per lamp per year, from what I've read...but that's a long time to make a ton of CO2. Too much emphasis anyway; CFLs are really aimed at people who already have electricity in their houses. --Wtshymanski (talk) 15:36, 11 April 2012 (UTC)
 * I haven't got a clue of how actual carbon trading works so I used 500kg/MWh based on some British proposed norm for power plant emissions. And happy to get such a ridiculously high value. I wasn't particularly impressed with the whole Sunlabob project, maybe you noticed ;-).
 * Frustrating article to edit it seems, judging by the archives. Ssscienccce (talk) 03:49, 12 April 2012 (UTC)
 * I think carbon trading is a little more complicated than taking out a classified ad saying "Give me $50 and I won't set fire to this pile of charcoal briquettes in my back yard." About the only way I can see that as being relevant to keorsene lamp replacement is if some group gets together and says "We'll replace 1 million kerosene lamps with , this will displace 100,000 tons per year of CO2 for 3 years, give us $1.5 million dollars and take the credit in your annual CO2 report". It's not going to be something J. Random Villager is going to access, not even if he convinces his whole community to go in on it with him. I just read that the world spends $48 billion a year on kerosene, about 20% of all spending on lighting, but that kerosene only makes 0.2% of the world's lumen-hours; it's really expensive light! --Wtshymanski (talk) 13:25, 12 April 2012 (UTC)

Electrical efficiency
The article only mentions the luminous efficiency/efficacy but does not mention the electrical efficiency. The latter would be defined by the energy (not visual brightness) of the light emitted by the phosphor (of filament in case of an incandescent lamp) divided by the total energy consumed by the lamp in the same time. Emitted light is all radiation emitted by the lamp in a controlled way, i.e. as defined by the emission spectrum of the phosphor/filament. Here, the efficiency of the incandescent lamp should be in the high 90's if the whole near-Planckian emission spectrum is taken as "emitted light" (and only convective heat or far infrared radiation re-emitted by heated lamp components would not be counted as such).

Are there any citeable numbers about the electrical efficienty of CFLs (and if possible also LEDs)?--SiriusB (talk) 14:09, 16 April 2012 (UTC)
 * I don't understand the importance of electrical efficiency when it's functional efficiency that the end user cares about. I think the important measure is the amount of visible light produced. Electrical efficiency seems to me to be of only minor technical interest. Joja  lozzo  14:51, 16 April 2012 (UTC)
 * That's true. If a lamp's purpose is to turn electricity into (visible) light, then measuring or stating its ability to produce other kinds of emission seems eccentric. --Nigelj (talk) 22:20, 16 April 2012 (UTC)

Starting time: why "delayed-on" lights are manufactured?
This section fails to mention why "instant on" didn't take over "delayed-on" lamps. Obviously, "delayed-on" is generally the usability defect, and users will likely notice it and will be displeased. So why they are still manufactured? Is there any benefit to them? Maybe they are cheaper to make? Maybe they are more efficient? Maybe they have higher brightness? Any references/information about this? Yurivict (talk) 19:50, 19 April 2012 (UTC)

Lamps that heat the filaments before attempting to strike the arc will have a longer life, most specifically, they will last for significantly more lamp starts. If the arc is struck with cold filaments, the lamp will initially run as a cold cathode tube, until the filament heats up to thermionic emission temperature via bombardment with electrons and ions. During this short period of cold cathode running (probably just a few seconds), the filament coating will suffer a very high rate of sputtering (wear), equivalent to several hours running time. 81.187.162.109 (talk) 22:55, 4 May 2012 (UTC)

Patents not mentioned in cite
""It has been the most popular type in North America since the mid-1990s, when the final expiration of patents allowed its manufacture.""

The cite is: http://www.lamptech.co.uk/Spec%20Sheets/Philips%20CFL%20Tornado.htm but that link doesn't mention anything about patents, just manufacturing difficulty. Douglas (talk) 12:56, 22 April 2012 (UTC)

Health study
I added information from a peer-reviewed study on cellular health effects of CFL exposure from the latest issue of *Photochemistry and Photobiology*. It would appear that the new information is somewhat contradictory to a phrase extant in the health section which suggests that the negative health effects of CFL exposure are minimal. The source used to support that assertion is certainly not a peer-reviewed journal, and in fact appears to be a possibly interest-conflicted advocacy site, so it would seem prudent to amend that statement in order to avoid internal contradiction in the article. However, considering my lack of standing, I have chosen to leave any such correction to other, possibly more established authors. In any case, the latter portion of that statement (viz, that the use "double-walled" bulbs can help mitigate and even eliminate UV-exposure risks) is now corroborated by the journal article, which is a far more reliable source, so it may be best to simply remove the statement citing the "greenfacts" website altogether. I only wanted to point out the contradiction here on the talk page in hopes that it might be resolved quickly~ Thanks in advance.70.113.16.249 (talk) 05:49, 24 July 2012 (UTC)
 * I agree about the greenfacts site reliability but the new in vitrio study doesn't necessarily contradict it. It seems to fit together with single walled bulbs posing some risk and double walls mitigating it. I rearranged things a bit and I think it's working. It would be good to have a secondary source that takes the new results and sorts things out for us. Other than stating the results, there's not much we can do with a primary source without engaging in OR and synthesis. Joja  lozzo  12:22, 24 July 2012 (UTC)
 * No, I think that your re-arrangement was well executed, and I am very happy with the results; at any rate, you've done a much better job than I would have done, so I feel that my decision to leave the final reconciliation to a more-experienced author has been vindicated :) The point about additional secondary sources is well taken; the article was only *just* published in the most recent journal issue, so it's a bit soon for secondary sources. I will keep my eye open for any good and reliable secondary distillations of the journal article and report back to this space if I feel they would serve the benefit of this article.  Anyway, thanks again for your assistance! :)70.113.16.249 (talk) 04:03, 28 July 2012 (UTC)

Alab results concerning operating emissions
A recently reported study on CFL emissions during operation conducted at the private environmental laboratory, Alab, does not appear to have been peer-reviewed yet. I cannot find any record of publication in any scientific journals. I agree with those who urge caution in including these preliminary results in Wikipedia. We should wait until there are reliable sources to support it. Joja lozzo  20:33, 13 August 2012 (UTC)
 * Agreed. Earlier today I also searched Google Scholar for the author, the lab, and the topic, and found nothing. --Nigelj (talk) 21:59, 13 August 2012 (UTC)


 * I found another very reliable source (in German) with more detailed information on the findings here.TMCk (talk) 01:07, 14 August 2012 (UTC) Note: I too find it way too early to add this vage information to the article.TMCk (talk) 01:09, 14 August 2012 (UTC)
 * Good find. Though it's still a journalist reporting on what Braun (who is clearly qualified to make the assertion) is saying in an interview. No scientific sources (or any primary written sources) yet.  Joja  lozzo  01:47, 14 August 2012 (UTC)


 * I doubt that scientific sources about this study will come forward unless of course new studies are conducted and this one mentioned as the article I linked to is from April 2011. On a personal note, I believe that the toxics released from the plastic encasing of those bulbs is rather low and far less than that from other common plastics found in every household, thus making it a negligent issue in comparison (and not likely to get much consideration in studies in the future). But that's just my take on it.TMCk (talk) 21:04, 15 August 2012 (UTC)


 * Well first of all, how do you know if the smog is released from the actual plastic? Estrogenic agents like phthalates are used in certain plastics, but where is the phenol supposed to come from? Even if it was smog from the plastic, other household plastics don't get leached into the air because they aren't in contact with heat like the bulbs are. — Preceding unsigned comment added by BigMatow (talk • contribs) 03:45, 17 August 2012 (UTC)


 * A: The chemicals in question are used in the production of plastics. B: Products made out of plastic and exposed to great heat: Lamp shield, cooking uttensils incl. containers used in microwaves, electric grills/toasters, any electronics incl. the computer you're typing your posts on, hair dryers, etc. The list is endless.BTW, CFL's don't get as hot as incandescent bulbs.TMCk (talk) 13:40, 17 August 2012 (UTC) And phenols too are used in plastics.TMCk (talk) 13:43, 17 August 2012 (UTC)

VA rating
The VA rating in the waveform picture caption was written on the base of the bulb, not a calculation (that I did, anyway). I'm not sure how to cite a lightbulb. --Wtshymanski (talk) 16:22, 5 December 2012 (UTC)
 * I have never seen a CFL with the VA rating on it anywhere. Why would the manufacturer put the VA rating on the base of the lamp?  99.9% of the buyers are unlikely to know what it signifies. DieSwartzPunkt (talk) 18:10, 5 December 2012 (UTC)
 * In the absence of readable references here, I refer you to our articles: Power factor says that there are two reasons why a PF may be less than unity - one is reactive loads leading to phase shifts in sinusoidal current graphs, and the other is distortion of the current graph away from sinusoidal shapes. In the former case, it says that VA calculations apply, and in the latter it says that 50 or 60 Hz filtering can reduce the harmonics and set the PF back to unity. In the Volt-ampere article it says "Volt-amperes are useful only in the context of alternating current (AC) circuits (sinusoidal voltages and currents of the same frequency)" (my emphasis).
 * Both of these articles chime with my own understanding of the situation. In short, I believe that it is legitimate to calculate a PF figure for a fluorescent bulb or tube, but that it is not legitimate to use this PF in any straightforward way to deduce a VA rating for that bulb or tube. I am willing to read modern references that may cover this in more detail than was ever taught to me in my distant student years, but I don't have any of my own, and I don't think a number stamped on a bulb necessarily represents a very thoughtful treatment of a complex problem.
 * The reason people want to talk about VA is that in the case of reactive loads you can say 100 W with a PF of 0.5 needs 200 VA of generation capacity. Therefore CFLs with a PF of 0.2 use the same or more power than incandescent bulbs. I don't think this is true, and I don't want to see such arguments creeping into the article unless they have the highest level of sourcing. --Nigelj (talk) 18:55, 5 December 2012 (UTC)
 * Only on Wikipedia. Isn't PF = Watts/VA?  Isn't V*A = VA? NOw I've got to find the farkn' bulb again and find what's printed on it. Maybe the volt-ampere article needs fixing, too. --Wtshymanski (talk) 20:00, 5 December 2012 (UTC)


 * A 20 watt CFL that draws this power with a power factor of 0.2 is not drawing the same power as a 100 watt incandescent bulb. It is drawing just the 20 watts that it claims to be drawing.  It is drawing the same current as the 100 watt light bulb but 80% of this current is 'wattless'.   Both lamps are drawing 100 volt-amps (VA) but this tells you nothing about the power wothout the power factor.  DieSwartzPunkt (talk) 12:39, 6 December 2012 (UTC)
 * Remember VAs do not add up and are useless factors for capacity and/or total load calculations. i.e. 100 units of 20VA bulbs do not make 2,000VA of generator load. 100 bulbs rated at 20VA each could total only 1,000 VAs. 174.118.142.187 (talk) 04:27, 9 December 2012 (UTC)
 * Yes, but, if it's 100 similar bulbs, *their* VA will add - all the bulbs will have similar current waveforms. If you were to mix incandescent lamps, discharge lamps, motors, capacitors, and drives, adding up the VA might give a very coarse approximation to the total load. If your objective is picking a wire size, this might be good enough. --Wtshymanski (talk) 17:05, 9 December 2012 (UTC)
 * The point was there is no point to putting the VA rating on a CFL and they have never done it on the many brands I have dealt with. 174.118.142.187 (talk) 02:16, 10 December 2012 (UTC)
 * Wasn't on a bulb I looked at...maybe I read it off the Scopemeter. Can't recall, it's been a busy couple of months. --Wtshymanski (talk) 15:19, 10 December 2012 (UTC)
 * But you claimed above that it was. 86.145.244.183 (talk) 17:41, 10 December 2012 (UTC)


 * I think that 'picking a wire size' is one of the worst examples of when VA should be used. In a distorted current waveform, a peak may lead to an large instantaneous current draw. This may repeat for some microseconds every fiftieth or sixtieth of a second, but the current draw time-averaged over the full fiftieth or sixtieth of a second - and therefore the heating effect of the current transmission - is exactly equivalent to the actual power rating, in watts, printed on the packaging, regardless of the 'PF'. Equally, given the filtering effect of substations, transformers, and transmission lines, such spikes in the current waveform are hardly felt at all at the generating station. That is even before you account for the averaging effect of all the different appliances in use in homes and workplaces. Almost everything that has an AC to DC power supply built in - televisions, computers, printers, satellite and radio receivers, draw their current unevenly through each AC cycle, but you don't hear any nonsense about how they're going to lead to the downfall of our distribution systems and the end of civilisation as we know it. If we're going to talk about PF and VA as relevant to CFLs in particular, then we need some very good sourcing (not WP:OR) as to why it is relevant per WP:DUE. If anyone has any, please list them here, so that we can decide on due weight in this context. --Nigelj (talk) 19:07, 10 December 2012 (UTC)
 * To be fair these CFL bulbs are relatively new and every bulb brand has different methods of marking them so Wtshy may just have seen VA on some. These bulbs act similar to HID lighting and most people working in the distribution field will be aware of the third harmonic problems with three phase transformers not utilizing zig-zag windings or other third harmonic reducing techniques. This problem is magnified by the usage of neutral reactors to reduce fault capacities in large distribution sources. Three phase third harmonics all add up to triple levels in the neutral and makes a mess of sensing systems as well as distributes enlarged voltage harmonics to customers. It is becoming a big problem and utilities are having to replace multi-million dollar transformers with compensating designs. Finding references for this phenomenum? Not easily. Many EEs have a hard time understanding it. 174.118.142.187 (talk) 04:18, 11 December 2012 (UTC)


 * Wire heating is directly related to current and current is VA/V. Arms takes into account for different waveform. 1Arms means that it will induce the same amount of heating effect on a piece of wire as 1A DC. Cantaloupe2 (talk) 08:42, 30 January 2013 (UTC)

"Peter Braun" at "Alab"
I have searched for any original publication by a "Peter Braun" at a research center in Berlin called "Alab" and have only found the one Telegraph article citing Braun. Who is he and what are his qualifications? What is "Alab?" I have "a lab" in my basement, but my "research" should not be cited for extreme claims in Wikipedia articles. Has this research been published anywhere? This alarmist article in the Telegraph has been quoted many times by websites, but at present falls far short of verifiability. We do not make scientific claims based only on "research" cited only in a mass circulation newspaper. If Braun's research gets published, this would deserve another look. For now, it does not belong in the article. Edison (talk) 01:16, 26 April 2011 (UTC)
 * A simple google would have shown that this is not "a lab" but indeed a research center named ALAB in Berlin, http://www.alab-berlin.de/ where they test for "solvents and other volatile organic compounds (VOC, MVOCs), chamber testing, surface emission measurements, formaldehyde and higher aldehydes, asbestos, synthetic mineral fibers (KMF ) isothiazolinones, phenols / cresols, chloroanisoles, polycyclic aromatic hydrocarbons (PAHs)" and where a Peter Brown does indeed work.
 * I mailed him and asked about this particular study and got the reply that one of the CFL tests was done for http://www.ndr.de/ and one for: http://www.gesundheitstipp.ch/onlineartikel/1062832/Sparlampen_im_Test_Nur_6_sind_gut
 * Translation of the latter: "K-Tip tested the CFLs on electrosmog and harmful emissions. All lamps emit toxic gases into the environment, and create smog."
 * So, even if the alarmist Telegraph article was poorly written, it is based on real tests. Do consumer and safety tests need to be published in a scientific journal to count?
 * Lorielle (talk) 18:11, 10 March 2013 (UTC)