# incandescent bulbs **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [February 3, 2012, 1:03pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645 "2012-02-03T13:03:53Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![david\_42](https://avatars.discourse-cdn.com/v4/letter/d/cc9497/32.png) [@david\_42](https://boards.straightdope.com/u/david_42)\ **Post date:** [February 3, 2012, 6:55pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/21 "2012-02-03T18:55:38Z")
Never heard of a heatpump, eh? My heatpump gives me 3.8 watts of heat for every watt of electricity used, and that’s all the way down to -17C. As a plus, I now have A/C for the summer. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 3, 2012, 7:57pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/22 "2012-02-03T19:57:23Z")
> [@david\_42](#): > > Never heard of a heatpump, eh? My heatpump gives me 3.8 watts of heat for every watt of electricity used, and that’s all the way down to -17C. As a plus, I now have A/C for the summer. Of course I’ve heard of heat pumps. They just weren’t within the scope of the comparison I made. I mean, you saw the words ‘resistive heater’ in my post? ---
**Author:** ![dangab](https://avatars.discourse-cdn.com/v4/letter/d/3e96dc/32.png) [@dangab](https://boards.straightdope.com/u/dangab)\ **Post date:** [February 3, 2012, 7:59pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/23 "2012-02-03T19:59:52Z")
> [@Una\_Persson](#): > > Link to the column: [http://www.straightdope.com/columns/read/3035/why-are-eco-fascists-trying-to-ban-incandescent-bulbs](http://www.straightdope.com/columns/read/3035/why-are-eco-fascists-trying-to-ban-incandescent-bulbs) > > First off, resistance electric heating is typically one of the least economical ways to heat a house, even if you do get a co-benefit of light. > > Second, even in cold climates can still get a net benefit from CFL bulbs: one Canadian study found that replacing just 5 incandescent lights with CFLs slightly increased household heating energy requirements, but overall reduced electrical costs by 3.7%, giving a payback period from 2.5 to 6 years for the cost of the lights. > > Institute for Research in Construction. _Benchmarking of energy savings associated with energy efficient lighting in houses._ Parekh, Anil et al. NRCC-50874, 2005. > > However, there are special cases where one can claim if most of their electrical power is supplied by hydroelectricity or nuclear power, and most of their heating by gas, then CFLs could be a net detriment in terms of GHG emissions. Outside of regions in Canada, France, Brazil, and a few other places here and there, that is not likely to be the case. For most of the United States it certainly wouldn’t be. I live in Europe in a country where electricity is generated mostly by burning gas and, to a smaller extent, by using nuclear power. Now the thing is that traditional lightbulbs are going to be withdrawn gradually from the market in the EU. I cannot agree with this. I have been using both kinds of bulbs in my house for years, and realized that they have their own place but one kind cannot be used across the board reasonably. As for the prices of bulbs, the difference is huge, 10-20x. I suspect that device manufacturers are comfortable with this EU policy, to put it mildly, because the can market their high-margin merchandise without being cannibalized by the cheaper line. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [February 3, 2012, 8:44pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/24 "2012-02-03T20:44:03Z")
> [@Tom\_Scud](#): > > Further, if you’re going to account for heating costs saved by using inefficient light bulbs, you’d also have to account for additional air conditioning and other cooling costs, unless you live in a climate where you never even turn on a fan in the summer. They accounted for air conditioning costs in the study. If you never used any A/C, the breakeven point was much further along. ---
**Author:** ![HenryG](https://avatars.discourse-cdn.com/v4/letter/h/eb8c5e/32.png) [@HenryG](https://boards.straightdope.com/u/HenryG)\ **Post date:** [February 3, 2012, 10:07pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/25 "2012-02-03T22:07:37Z")
As well asignoring the benefits of heating from bulbs, enthusiasts (let’s be polite, eh?) ignore a couple of other aspects: - poor design of some of these new globes (more “shoulder” than incandescents) means they won’t fit existing bulb-holders, so there is the waste of throwing out the bulbs or throwing out your perfectly usable standard lamps - the claimed light output seems far less than from the incandescents they are supposed to replace. A new 15W is not comparable to the old 75W. To get the same output I need more like a 30W, so the running-cost saving are halved. Factor in the increased purchase cost and the econsomics aren’t compelling ---
**Author:** ![drewder](https://avatars.discourse-cdn.com/v4/letter/d/57b2e6/32.png) [@drewder](https://boards.straightdope.com/u/drewder)\ **Post date:** [February 3, 2012, 10:07pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/26 "2012-02-03T22:07:44Z")
I think we also have to take into account the dangers of CFLs that edison light bulbs don’t have. 1. a CFL contains mercury whch is very dangerous if the bulb breaks. > [@](#): > > From the EPA website > Before Cleanup > •Have people and pets leave the room. > •Air out the room for 5-10 minutes by opening a window or door to the outdoor environment. > •Shut off the central forced air heating/air-conditioning system, if you have one. > •Collect materials needed to clean up broken bulb: > ◦stiff paper or cardboard; > ◦sticky tape; > ◦damp paper towels or disposable wet wipes (for hard surfaces); and > ◦a glass jar with a metal lid or a sealable plastic bag. > > During Cleanup > •DO NOT VACUUM. Vacuuming is not recommended unless broken glass remains after all other cleanup steps have been taken. Vacuuming could spread mercury-containing powder or mercury vapor. > •Be thorough in collecting broken glass and visible powder. > •Place cleanup materials in a sealable container. > > After Cleanup > •Promptly place all bulb debris and cleanup materials outdoors in a trash container or protected area until materials can be disposed of properly. Avoid leaving any bulb fragments or cleanup materials indoors. > •If practical, continue to air out the room where the bulb was broken and leave the heating/air conditioning system shut off for several hours. I suspect that the mercury mining process is pretty destructive to the environment but I can’t say for sure 2. CFLs cause more migranes from those who get them. ---
**Author:** ![HenryG](https://avatars.discourse-cdn.com/v4/letter/h/eb8c5e/32.png) [@HenryG](https://boards.straightdope.com/u/HenryG)\ **Post date:** [February 3, 2012, 10:29pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/27 "2012-02-03T22:29:02Z")
Having read all the responses in this thread, and spent an hour searching the web, may I refer readers to [http://sound.westhost.com/articles/incandescent.htm](http://sound.westhost.com/articles/incandescent.htm) which I wish I read before I made my simplistic comments Cheers - HMG ---
**Author:** ![gamerunknown](https://avatars.discourse-cdn.com/v4/letter/g/6bbea6/32.png) [@gamerunknown](https://boards.straightdope.com/u/gamerunknown)\ **Post date:** [February 3, 2012, 10:46pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/28 "2012-02-03T22:46:47Z")
> [@](#): > > having government shove social mandates down peoples’ throats Yeah, curse them for ending child labour and whatnot. ---
**Author:** ![Michael63129](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@Michael63129](https://boards.straightdope.com/u/Michael63129)\ **Post date:** [February 3, 2012, 11:22pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/29 "2012-02-03T23:22:38Z")
> [@drewder](#): > > I think we also have to take into account the dangers of CFLs that edison light bulbs don’t have. > > 1. a CFL contains mercury whch is very dangerous if the bulb breaks. > > I suspect that the mercury mining process is pretty destructive to the environment but I can’t say for sure > 2. CFLs cause more migranes from those who get them. If your electricity comes from coal, as [mine almost certainly does](http://www.eia.gov/state/state-energy-profiles.cfm?sid=MO) (there’s a coal power plant just a couple miles away from where I live plus a couple more nearby, although there are two nearby gas power plants in Illinois), then [more mercury is emitted by burning coal](http://en.wikipedia.org/wiki/Compact_fluorescent_lamp#Environmental_issues) to power an incandescent than is used in a CFL and to power it (note also that even if no CFLs were recycled, they’d account for about 0.1% of mercury emissions in the U.S.). Now, not everybody gets such a high proportion of electricity from coal, but there are LED bulbs and I expect that they will improve enough to easily compete with and replace CFLs in the near future. Also, with regards to fluorescent lights in general, I have always wondered why they can’t make one that has no mercury in it; after all, white LEDs use a phosphor to convert blue light to yellow light, which mixes to make white light, so UV (produced by mercury vapor) isn’t necessary. Theoretically, you could even use a mixture of gasses that would produce white light in itself, then there would be no losses in converting it to a different wavelength with phosphors. ---
**Author:** ![John\_W.Kennedy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_w.kennedy/32/1031_2.png) [@John\_W.Kennedy](https://boards.straightdope.com/u/John_W.Kennedy)\ **Post date:** [February 4, 2012, 12:03am UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/30 "2012-02-04T00:03:44Z")
Incandescent bulbs are not remotely near sunlight, as any photographer knows. ---
**Author:** ![drewder](https://avatars.discourse-cdn.com/v4/letter/d/57b2e6/32.png) [@drewder](https://boards.straightdope.com/u/drewder)\ **Post date:** [February 4, 2012, 12:11am UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/31 "2012-02-04T00:11:38Z")
> [@Michael63129](#): > > If your electricity comes from coal, as [mine almost certainly does](http://www.eia.gov/state/state-energy-profiles.cfm?sid=MO) (there’s a coal power plant just a couple miles away from where I live plus a couple more nearby, although there are two nearby gas power plants in Illinois), then [more mercury is emitted by burning coal](http://en.wikipedia.org/wiki/Compact_fluorescent_lamp#Environmental_issues) to power an incandescent than is used in a CFL and to power it (note also that even if no CFLs were recycled, they’d account for about 0.1% of mercury emissions in the U.S.). > > Now, not everybody gets such a high proportion of electricity from coal, but there are LED bulbs and I expect that they will improve enough to easily compete with and replace CFLs in the near future. > > Also, with regards to fluorescent lights in general, I have always wondered why they can’t make one that has no mercury in it; after all, white LEDs use a phosphor to convert blue light to yellow light, which mixes to make white light, so UV (produced by mercury vapor) isn’t necessary. Theoretically, you could even use a mixture of gasses that would produce white light in itself, then there would be no losses in converting it to a different wavelength with phosphors. Really the enviromental issue is more of an afterthought for me. Having the mercury inside my house waiting to poison my family if someone drops a bulb is more my pressing concern. Also CFLs give me headaches ---
**Author:** ![Randvek](https://avatars.discourse-cdn.com/v4/letter/r/a6a055/32.png) [@Randvek](https://boards.straightdope.com/u/Randvek)\ **Post date:** [February 4, 2012, 2:03am UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/32 "2012-02-04T02:03:36Z")
Am I the only one disappointed that Unca Cece says that not having the need to build 30 more power plants is insignificant? Sure, that’s only a .5% savings, but when you consider the energy (and resulting pollution) that the US puts out, slightly annoying lightbulbs seems like a more than fair trade. ---
**Author:** ![drewder](https://avatars.discourse-cdn.com/v4/letter/d/57b2e6/32.png) [@drewder](https://boards.straightdope.com/u/drewder)\ **Post date:** [February 4, 2012, 3:54am UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/33 "2012-02-04T03:54:24Z")
> [@Randvek](#): > > Am I the only one disappointed that Unca Cece says that not having the need to build 30 more power plants is insignificant? Sure, that’s only a .5% savings, but when you consider the energy (and resulting pollution) that the US puts out, slightly annoying lightbulbs seems like a more than fair trade. It seems like an over estimate anyway since the power plants we already have seem to be powering as many incandescent light bulbs as we use and the number would naturally decrease with time as people decide to change their light bulb preference. ---
**Author:** ![Anthony\_Kaye](https://avatars.discourse-cdn.com/v4/letter/a/ed8c4c/32.png) [@Anthony\_Kaye](https://boards.straightdope.com/u/Anthony_Kaye)\ **Post date:** [February 4, 2012, 4:00am UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/34 "2012-02-04T04:00:04Z")
LEDs are just starting to take off here in Britland. They were a ludicrous £30 ($45) last year, but are now an almost reasonable £10-12. I came across one with a big ‘40’ on the box. Deciding this was Wattage equivalent I bought it. It was hopelessly dim. ‘40’ was lumens-divide by 3 to convert to Watts. However it only used 2W of current. It now lives in the outside light, giving me a dim but cheap view of the rapists, mass murderers, etc stalking the garden. A sucker for punishment, I bought another that took 9W current. This was much brighter. I put it in my bedside light. Next day I knocked it over and smashed the bulb-LEDs are much heavier than incandescents, due to the electronics in the base. It still works though-the glass cap is only there to diffuse the glow. Switching it on in the middle of the night is a bit fraught though- the shards of glass make it a bit tricky. Also the base of the bulb gets surprisingly hot due to said electronics- this is why it is ribbed. I’m now retired- it’s a sobering thought that, if these bulbs last as long as is claimed, they’ll be continuing to glow long after I have ceased to. I shall miss the old incandescents. They were of course a British invention. A fellow called Joseph Swann beat Edison to it by a year or so. They eventually agreed that Edison would have the patent rights in the U.S. and Swann in the rest of the world, finally joining forces in the Ediswann company. ---
**Author:** ![John\_W.Kennedy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_w.kennedy/32/1031_2.png) [@John\_W.Kennedy](https://boards.straightdope.com/u/John_W.Kennedy)\ **Post date:** [February 4, 2012, 8:31pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/35 "2012-02-04T20:31:10Z")
A great many inventors produced incandescent lighting systems throughout the 19th and early 20th centuries. Swan (note spelling) and Edison were only two of them. They do seem to have been responsible for the first large-scale installations, though. ---
**Author:** ![av8rmike](https://avatars.discourse-cdn.com/v4/letter/a/edb3f5/32.png) [@av8rmike](https://boards.straightdope.com/u/av8rmike)\ **Post date:** [February 4, 2012, 9:58pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/36 "2012-02-04T21:58:30Z")
> [@drewder](#): > > 1. CFLs cause more migranes from those who get them. Cecil’s assertion that “you’d be a fool not to use CFLs” also neglects people (like my girlfriend) who have vision problems. ---
**Author:** ![TBG](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@TBG](https://boards.straightdope.com/u/TBG)\ **Post date:** [February 4, 2012, 10:05pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/37 "2012-02-04T22:05:49Z")
Why does Cecil claim “Although halogen bulbs don’t offer much of an energy savings over ordinary incandescents, compact fluorescents sure do, and \*\*you’d be a fool not to use them whenever you could \*\*” (bolding mine) when the rest of his article doesn’t show it to be foolish at all? It’s a good, balanced article, IMO, save for this needlessly inflammatory line. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 4, 2012, 11:50pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/38 "2012-02-04T23:50:10Z")
What’s inflammatory about it? ---
**Author:** ![Blackfaer](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@Blackfaer](https://boards.straightdope.com/u/Blackfaer)\ **Post date:** [February 4, 2012, 11:54pm UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/39 "2012-02-04T23:54:22Z")
The heat gain is pretty minimal, and while the lost heat in the winter increases your heating needs, much of the country uses air conditioning or fans for cooling the other half the year, which is more wattage per therm than the heating costs. What I noticed Cecil didn’t come up with is that for color-sensitive applications, or for applications where dimming is needed, fluorescents and LEDs have serious deficiencies compared to halogen or incandescents. I actually work with light for a living, so my considerations aren’t that of your average homeowner, but if you’re trying to choose what socks you want to wear to match your shirt, I wouldn’t advise making those decisions under LED or Fluorescent lighting. The color rendering index (CRI) is a measure of how perfectly a light source will reproduce every color of the materials it is lighting. Incandescents have a CRI of 100, like the sun; halogens do as well. The light they put out is full-spectrum, there’s no spikes or dips in the light that generates what we see as white. Typical CFL lamps have a CRI in the 65-85 range. Fancy expensive CFLs can get up to 95, but that’s still not enough to reproduce every color. If for instance the tint that turns your green socks to brown is the precise wavelength that’s missing from the light source, you’ll see brown socks that will turn green when you walk outside. LED’s have similar problems but are a rapidly developing technology; 3 years ago the best CRI a white LED could get was about 40. Now they are in the 90s, but again still have flaws. As to dimming, if you need to be able to adjust the level of your lighting on a dimmer, you’re almost completely out of luck with CFLs - some can work with specially-designed dimmers but you’ll have to swap out your wall dimmer with a much more expensive one. LED’s can be dimmed but use a completely different technology that’s not compatible with just plugging it into your wall, and the pricing is even higher for dimmable LED systems than it is for simple replacement lamps, which as Cecil points out cost upwards of $50. That said, LED’s have a life expectancy dozens if not hundreds of times longer than CFL’s. As Cecil points out, Halogens aren’t that much more efficient than incandescents, and they get a lot hotter. But they are frequently used when you need a much brighter light - I work with 575-4000 watt halogens - and they provide a perfect CRI and complete dimmer capability with greater efficiency than incandescents, and depending on the individual manufacture can have a significantly longer life span than an incandescent. One problem with halogens, however, is that you shouldn’t touch the glass envelope (the outside of the bulb) with your skin - the oils we leave behind boil against the glass and create a weak point which causes the lamps to die early, sometimes with small explosions. ---
**Author:** ![Blackfaer](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@Blackfaer](https://boards.straightdope.com/u/Blackfaer)\ **Post date:** [February 5, 2012, 12:00am UTC](https://boards.straightdope.com/t/incandescent-bulbs/611645/40 "2012-02-05T00:00:59Z")
> [@John\_W.Kennedy](#): > > Incandescent bulbs are not remotely near sunlight, as any photographer knows. You’re talking about color temperature, but incandescents and halogens work just like the sun does, by generating combustion and outputting white light. The adjustments between the intensely bright and high-kelvin color temperature of the sun and the much dimmer and low-kelvin color temperature of the incandescent 60w light bulb is a necessary adjustment in photographic work. But it’s nothing compared to the changes wreaked by moving from sunlight or halogen/incandescent lighting into LED/CFL/Fluorescent lighting. Incandescents still have a perfect CRI, so once you white-balance your camera, you’ll get the same colors as you did outdoors. But fluorescents and LEDs only reproduce certain parts of the spectrum, which appear white to our limited 4-receptor eyes, but can completely change the appearance of colors even after white balancing. Incandescents ARE quite like sunlight; color temperature is only a minor change. Even a sunny day changes in color temperature pretty dramatically, just try white balancing right after sunrise on a cloudy morning and then using that balance to photograph or film something on a clear day just after noon. The CT change is even greater in this scenario than going from a warm day to a incandescent light. [Previous page](https://boards.straightdope.com/t/incandescent-bulbs/611645.md?page=1) [Next page](https://boards.straightdope.com/t/incandescent-bulbs/611645.md?page=3)