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April 22, 2008 8:50 AM   Subscribe

Unscrew America!! Flash 9 Activism designed to promote interest/activity in replacing regular old incandescent lightbulbs with energy-efficient CFL and LED bulbs.
posted by psmealey (69 comments total) 6 users marked this as a favorite

 
I hesitate to say this because I know the world is burning while I fiddle, etcetera, but I recently tried to replace the incandescent bulb on my night table with a CFL. The result was horrendous -- it was hard to read, and our bed suddenly looked like a bed in some sort of clinic. Yes, I should probably have tried a variety of CFLs before swapping the Soft White back in, because I know they have a wide range of color temperatures and so forth.

I'm typing this under the CFL I used to replace my desk light. It's OK. But when I look directly at the brightest area of the lampshade, my eyes hurt a little, as if there was a subliminal flicker. When I look at a similar shade hiding an incandescent bulb, my eyes whisper "Yes," as if the light was nourishing somehow.

I am not arguing against global warming, green politics, or anything else. We should certainly replace as many incandescent bulbs as we can quickly. I'm just sayin'.... does anyone else have this rarely-voiced reservations about the current state of CFLs?

Maybe I should conduct a double-blind test so I can make sure my brain is not deceiving my eyes.
posted by digaman at 9:03 AM on April 22, 2008 [3 favorites]


Unscrew America!
[Insert snide remark about George W. Bush here.]
posted by JDHarper at 9:07 AM on April 22, 2008 [3 favorites]


it's probably worth pointing out at some point that LED bulbs aren't "more efficient" unless you don't have to heat your house. That "wasted energy" from incandescent bulbs is presumably lost as heat, so it just results in you having to heat your house less. Of course, in the summer when you're not heating the house then it probably is wasted energy, but then you maybe don't really need the light on in the summer that much anyway. LED bulbs are probably a good thing (I've got lots in my house), but I'm always a bit cynical when the answer to ecological problems involves just buying more stuff.....
posted by silence at 9:07 AM on April 22, 2008 [2 favorites]


does anyone else have this rarely-voiced reservations about the current state of CFLs?

I do, for the same reason: I feel a buzz behind my eyes when I'm under a fluorescent.

Also, in my own experiences with CFLs, if I'm lucky enough to have a fixture which can house one, they are poorly made and break easily, so if I'm throwing them in the trash faster, the cost savings and pollution offset doesn't seem as realistic as promised.
posted by Blazecock Pileon at 9:08 AM on April 22, 2008


digaman's got a good point too. We tried replacing the three bulbs in our ceiling fan with CFLs, but we got some weird kind that take about a minute to get up to full brightness. You flip the switch, and the room is only slightly less dark than it was before.

And they made our couches look green.

A different brand of CFLs that I put into my bedroom light fixture failed within a month, when the selling point of CFLs for me is that I don't have to replace them for *years*. In go the incandescents, which give off a prettier light anyways.

The point is that CFLs aren't mature enough as a product to rely on yet. And, really, why not wait for LED bulbs, in development now, which contain no mercury and which won't need to be replaced in your lifetime?
posted by JDHarper at 9:11 AM on April 22, 2008


Broken CFLs are a pain to deal with. I hope LED bulbs get cheaper soon. (I've got lots of CFLs, mind you -- I'd just rather have LED bulbs.)
posted by Zed_Lopez at 9:12 AM on April 22, 2008


digaman, your concern is most definitely not rarely voiced. Not all CFLs are created equal, as you know. But it's true that even the best ones don't reproduce colours as well. You might try giving energy-saving halogens a shot. I'm not sure how much they cost, and they aren't as efficient as CFLs, but they produce light that's just as nice as incandescents and they use, according to Philips, 30-47% less energy. CFLs use, I think, 75% less, so the gain isn't as dramatic. But like you, I'm not a huge fan of the light that CFLs give off. Though I've found that the Philips CFL bulbs don't have problems with flickering, for what that's worth.

I really am not going to give LEDs a shot yet. Given the harsh, sterile light I've seen them put out, I think they're probably a few years away from being a decent alternative.
posted by Dasein at 9:12 AM on April 22, 2008 [1 favorite]


Also, in my own experiences with CFLs, if I'm lucky enough to have a fixture which can house one, they are poorly made and break easily, so if I'm throwing them in the trash faster, the cost savings and pollution offset doesn't seem as realistic as promised.

My experience has been a little different. I spend the majority of my time at home in the basement, where my office/rehearsal space/recording studio is. I have had CFLs installedin regular overhead ceramic fixtures for over a year and a half and going strong. I have had to replace incandescent bulbs in other locations 2-4 times in other locations over a similar duration.

Of course, I'm sure my mixer board, PA system, Mac, guitar and bass amplifiers more than offset whatever savings I'm getting fromt he CFLs, but that's another discussion for a different day.
posted by psmealey at 9:13 AM on April 22, 2008


That "wasted energy" from incandescent bulbs is presumably lost as heat, so it just results in you having to heat your house less.

Well, sort of. If your goal is to heat the air immediately around the light bulbs. Which it may be, I guess, if you're using them as a reading light in a place that you also want to be warm. But unless you've got some other kind of airflow going on, simply putting a point source of heat in a room isn't a particularly efficient way to turn electricity into heat.
posted by gurple at 9:14 AM on April 22, 2008


I've got tons of CFLs in my ceiling fans. They're fine and, surprisingly, don't cause any buzz in any of my audio junk (of which there is a lot, much of which is poor quality and very susceptible to such things). Color temperature seems close enough, and the only one I've had to replace so far was in a really lousy lamp, which I'd assume caused it to fail. Plus they weren't terribly expensive. I'm okay with these things so far.
posted by uncleozzy at 9:19 AM on April 22, 2008


I actually like CFLs and probably have them in 90% of my fixtures. You have to be sure and look at the color temperature rating if you are sensitive to that sort of thing, and I stay away from no-name brands because some of them don't last and they tend to take longer to get to full brightness. Sometimes, though, I actually like that they don't come to full brightness right away; when I am in a very dark room I don't get dazzled with bright light as soon as I flip the switch. Unfortunately I have noticed that a lot of ceiling fan manufacturers have started putting candelabra sized sockets in their light fixtures which makes CFLs harder, but not impossible to find. The other problem is that dimmable CFLs are very hard to find, at least where I am. On the other hand, they are great for hard-to-get to fixtures where I only have to change them every few years. I imagine in a few years LEDs will replace them, it seems that technology is moving along pretty fast.
posted by TedW at 9:23 AM on April 22, 2008


I worry about LEDs being oversold. They don't last forever (their brightness slowly dims, and heat exposure shortens their lifespan) and their color spectra is uneven and noncontinuous (meaning that objects illuminated by white LEDs can take odd colors, and can contribute to harsh/sterile lighting). For now they look like a good alternative but they're not a last resort.
posted by ardgedee at 9:25 AM on April 22, 2008


I agree that some CFLs don't belong in some places though I wouldn't call this reservation "rarely-voiced". It's the first thing nearly everyone says after how much energy they save.

We just use them places where the quality of light isn't so important and/or the hours of light are high. Main, dark hallway: Yes. Above bathroom mirror: No.

I haven't found incandescents to be that incredibly awesome at color either, though. Every year, when it starts being light later in the evening, I'm struck by how different the inside of the house looks lit by the sun. So perhaps the issue less about inferiority and more about retraining the eye to accept a different subpar situation.
posted by DU at 9:27 AM on April 22, 2008 [2 favorites]


...the only one I've had to replace so far was in a really lousy lamp, which I'd assume caused it to fail...

Heat can cause CFLs to fail prematurely, which is why some are labeled "not suitable for enclosed fixtures." I have also read that some CFLs fail early when mounted upside down, also because of heat. That may or may not apply to your fixture, but it is something that not a lot of people seem to know about CFLs
posted by TedW at 9:29 AM on April 22, 2008


Cheap CFLs suck for light quality. I prefer full spectrum 5000K lamps, but some people prefer the the warmer 3200K ones. In particular, I like the Sylvania CFL23EL/MINI5K for 100W replacement and the CFL13EL/MINI5K for 60W replacement.

They're not dirt cheap -- they run about $7 per -- but they put out good, solid light with good (but not perfect) color rendition. There are better color lights out there -- the trick is to look up the CRI (Color Rendering Index.) 100 is perfect, as in incandescent, 70 are typical for cheap fluorescents. These lamps are either 87 or 91, depending on which spec sheet you believe.

If you prefer warmer, try to find the 3200K version of these - I haven't seen them, but I haven't looked. Given the rate of replacement and the rapidly rising cost of electricity, the payback time is dropping rapidly.

Now: Where to not use CFL:

1) On autoswitches. CFLs don't have a burn lifetime so much as they have a cycle lifetime. Flick them on and off a hundred times a night, and they'll fail quickly.

2) In real cold. They get dimmer with cold, so on cold winter nights, they're not really happy outside.

3) In enclosed fixtures, unless they're specifically rated to be there. CFLs react poorly to heat, enclosed fixtures can trap heat. There are CFLs rated for this duty.

4) Installed the wrong way. Many CFLs are rated to burn base-down only. Burning them base up concentrates the heat on the ballast, and it fails. This seems to be less of a problem on newer lamps, and there are CLFs made explicitly to burn base up -- often, these are also rated to burn in enclosed fixtures.

As with all things, you get what you pay for. $1 hypercheap CFLs suck. Don't buy them, or if you do, don't judge all CFLs by their performance.
posted by eriko at 9:32 AM on April 22, 2008 [9 favorites]


their color spectra is uneven and noncontinuous (meaning that objects illuminated by white LEDs can take odd colors, and can contribute to harsh/sterile lighting)

This is something I don't get about LEDs. There is (or was) this huge race to get pure white LEDs. But you need more than one LED to light a room anyway, right? So why not use a bunch of reds, blues and greens (of varying wavelengths to even out the spectrum)? Put the whole thing in a single package so it seems to be emitting white light and bam, you are done.

In fact, ISTR that that was exactly what they were doing with white LEDs in the first place (otherwise how are you going to get white light? there's no white photons). So maybe the issue is that finding those varying wavelengths and making them cheap isn't so easy.
posted by DU at 9:33 AM on April 22, 2008


Hm, I wasn't aware of the enclosed/inverted problems. Nearly all of mine are mounted upside-down, and have been burning for over a year that way. Must be okay for these guys. I'll have to read the label next time I replace one.
posted by uncleozzy at 9:45 AM on April 22, 2008


Honest and ignorant question: Is it really environmentally friendly to actively go through your home, rip out all the incandescents and replace them with CFLs?

I've been replacing with CFLs gradually as my incandescents burn out (with decent results), but what about the waste of the incandescent bulb and the energy that went into producing it? What about the energy that goes into the packaging that comes with the new CFLs?

I get that CFLs last a really long time, so perhaps a year's worth of life isn't that big a deal in the long run, but it seems strange to be exhorted by environmental groups to throw something away. Has someone examined this tradeoff in a straightforward fashion?
posted by gurple at 9:49 AM on April 22, 2008


> So why not use a bunch of reds, blues and greens (of varying wavelengths to even out the spectrum)? Put the whole thing in a single package so it seems to be emitting white light and bam, you are done.

A few problems with that: it makes for a bigger package and it generates color fringe in shadows and highlights. Primarily, it doesn't guarantee an even color spectrum anyway: If the three diodes can't cover the full spectrum evenly and with proper falloff where they overlap, for all that work you'll end up with a 'white' light considerably less appealing than what you were trying to replace.

An acquaintance did interior decoration in a room illuminated by LEDs. It looks like the architect solved the color problem by embedding the light in recesses near the ceiling, so that the lamps' output was mediated by the color values of the reflecting surfaces. In a situation like that, too, designers can experiment with detailed, balanced light installation. It's pretty far removed from small, convenient gadgets that screw into lamp sockets.
posted by ardgedee at 9:50 AM on April 22, 2008


All the CFL bulbs I've tried in regular living quarters (they're fine in the garage, I've decided) range from ghastly-harsh-depressing to subtly wrong. It's like, I can see, but the room still feels like it's dark. Or like the light's not bouncing around the room correctly. It feels like a spotlight coming from the light source instead of filling the room with ambient light.
posted by straight at 9:51 AM on April 22, 2008


> They're not dirt cheap -- they run about $7 per -- but they put out good, solid light with good (but not perfect) color rendition. There are better color lights out there -- the trick is to look up the CRI (Color Rendering Index.) 100 is perfect, as in incandescent, 70 are typical for cheap fluorescents. These lamps are either 87 or 91, depending on which spec sheet you believe.

If incandescent is 100, then I don't have a lot of faith in this index. Incandescent lights give off a warm, yellow, but flawed color. Shouldn't sunlight be 100, perfect?
posted by meowzilla at 9:56 AM on April 22, 2008 [4 favorites]


I guess it's also worth noting that perfect evenness across the full visible light spectrum is presumed unnecessary and possibly unappealing. What human eyes usually want is a 'pure white light' that's biased in different ways for different contexts.
posted by ardgedee at 9:56 AM on April 22, 2008


I <3 my CFLs. I really don't know what you're all on about, my whole house is nearly incandescent-free.
posted by Skorgu at 10:00 AM on April 22, 2008


I think LEDs will mature pretty quickly -- this is something I've been watching in the caving community for a while, now. When cavers first started to switch over to LEDs 5 or 6 years ago, they were invariably blue-hued and feeble, even the ones with the 12-bulb arrays that were 700 dollars. Recently, though, I've had the pleasure of borrowing a Stenlight on a couple of trips, and they're both bright as hell, and indistinguishable from incandescent in color (my Nikon D50 thinks they're green, but I can't tell). I think I'm finally retiring my Guy's Dropper (carbide) lamp, as soon as I can afford one.

Compact Fluorescents will hopefully be a short-term stop gap until LEDs get affordable. I live in Texas, where we run the AC 9 months out of the year, so the savings battling the heat on incandescents will be good for me, too.
posted by Devils Rancher at 10:06 AM on April 22, 2008


I bought a couple of the Philips Halogen√° bulbs mentioned by Dasein. I'm happy with them, though I wish I could see an independent test of their light output & energy consumption. I don't like the CFL mercury disposal problem; none of my electricity is from coal so I wouldn't be reducing another mercury pollution source by switching to CFL.
posted by D.C. at 10:13 AM on April 22, 2008


To actually comment on the Unscrew America site, it is pretty neat and fun to navigate, but with all movement I feel queasy after a while, like I have been watching Cloverfield or The Blair WItch Project.
posted by TedW at 10:15 AM on April 22, 2008 [2 favorites]


What colour or type do you use Skorgu?

I'm looking for one that isn't so harsh. I have a few spots around the house that I have to have the incandescents in because of the harsh light that the CFLs give off. I'd switch all of them if I could fine a warmer replacement.
posted by joelf at 10:17 AM on April 22, 2008


I'm always a bit cynical when the answer to ecological problems involves just buying more stuff.....

Everyone should be cynical in this way. Unfortunately, for most Americans, shopping is easier than thinking. CFL's are good for some applications, not so good for others. Using less electricity is pretty much good all the time. You don't have to make a purchase to do so.
posted by oneirodynia at 10:21 AM on April 22, 2008


Caution: Do not use LEDs in Boston.
posted by Artw at 10:30 AM on April 22, 2008 [5 favorites]


If incandescent is 100, then I don't have a lot of faith in this index.

Incandescents rate 100 because they put out a smooth spectral curve of light across the spectrum. So does the Sun -- but the peak of that spectral curve is higher -- 5200K, as opposed to the 3000K of incandescent lamps.

Both emit light that close to the Black Body Radiation Curve. A Black Body is a theoretical construct of a object that absorbs all energy that hits it, reflecting none. As it warms, it will glow with a characteristic spectral curve -- the peak of that spectrum moves higher in frequency as the object warms, so a 5200K black body will emit light that appears bluer to use than a 3000K black body.

Our brains can adjust to that, though, which is why the CRI for both is 100. Fluorescent spectral curvers aren't black body curves -- they have spikes and dips, depending on frequency, thus, they don't render colors accurately.

The opposite of a incandescent lamp in CRI is the low pressure sodium lamp. Very efficient, but it has a CRI of 0 -- it emits all of its light in few very narrow bands of yellow, so our color vision is at a loss when it comes to seeing colors under that lamp. The more common High Pressure sodium does have at least some other colors, but it still has a miserable CRI of 22.
posted by eriko at 10:31 AM on April 22, 2008 [14 favorites]


They're not dirt cheap -- they run about $7 per -- but they put out good, solid light with good (but not perfect) color rendition. There are better color lights out there -- the trick is to look up the CRI (Color Rendering Index.) 100 is perfect, as in incandescent, 70 are typical for cheap fluorescents. These lamps are either 87 or 91, depending on which spec sheet you believe.

This is why I only use CFLs in the basement and garage. The light tends to be crappy and frankly it's a hell of a lot easier just to grab a soft white incandescent .
posted by MikeMc at 10:32 AM on April 22, 2008


Where to not use CFL:


5. In bedside table-lamps, and in any lamps that kids or pets can easily knock over.

CFLs release mercury when broken and it's a hassle to clean up thoroughly (also see link above). Don't put them in lamps that can be knocked over.
posted by LobsterMitten at 10:34 AM on April 22, 2008


I have a couple of CFLs in my house, and they're fine in the applications where I have them.

The problem I have with CFLs though is that we have an awful lot of recessed lighting, and a lot of it is on fancy Lutron dimmer systems, so CFLs won't work there. Plus, CFLs do contain mercury, which is a concern to me, in that their end-of-life requires either special disposal or specialized recycling. And lastly, I firmly believe that CFLs are a transitional technology, and that LEDs really are the way forward - the jury's still out on the dimmer problem, though - so I'd rather not replace all my incandescents with CFLs and then have to replace the CFLs with LEDs.

The Lutrons (like most solid-state dimmers) work not by lowering the voltage to the lamp, but by varying the mark/space ratio between 100% on and 100% off; this works fine for incandescents but will likely suck donkey balls (sorry, technical term) when used with LEDs, which have almost instantaneous on/off characteristics, leading to horrendous flicker when dimmed.

Maybe we should go back to candles.
posted by kcds at 10:37 AM on April 22, 2008


Interesting, I've never heard some of the limitations of CFLs before - especially mounting orientation and installation in fixtures. I replaced all the bulbs in my apartment with CFLs last year with the generic Home Depot brand, and I haven't had a complaint yet. They're mounted upside down in enclosed ceiling fixtures and I haven't lost one or been disappointed with the brightness or color. Then again, my apartment is bright red so maybe it could use some cooler light.
posted by backseatpilot at 10:42 AM on April 22, 2008


The heedless, headlong, irrational and fundamentally stupid rush to CFLs has just about cost me my appetite for all intiatives 'green.' If we can't get something this simple right, what real hope is there for the ever-lengthening menu of insanely intricate and almost intractable environmental difficulties we must somehow chew our way through in the next 50-75 years to avoid demographic catastrophe?

Aside from the issues of mercury pollution (which cut against CFLs absolutely decisively, in my opinion), consider this from the BBC about direct health effects of exposure to the blue light of CFLs:

Low-energy bulbs 'worsen rashes'

Low-energy light bulb
Energy saving bulbs could reduce carbon dioxide emissions
The switch to energy-saving light bulbs may put thousands at risk of painful skin reactions, health charities warn.

Fluorescent bulbs can exacerbate skin rashes in people with photosensitive skin conditions, experts said.

The government is planning to prevent the sale of conventional bulbs by 2011 to cut carbon dioxide emissions.

Several groups including the British Association of Dermatologists called for exemptions to allow those affected to continue using traditional bulbs.

But representatives of the lighting industry said there would be alternatives to fluorescent lighting available.

Health conditions which can involve some form of light sensitivity, include the auto-immune disease lupus, the genetic disorder Xeroderma Pigmentosum (XP), certain forms of eczema and dermatitis, photosensitivity, and porphyria.


I think this problem is much, much worse and more extensive than this article suggests. ADD and ADHD, for example, are beginning to look as if they have an autoimmune component, as well as autism and autism spectrum disorders, along with schizophrenia and its many fellow travelers, and I believe blue light will turn out to worsen all these conditions as well.

I also think the malaise digaman captures so perfectly:

But when I look directly at the brightest area of the lampshade, my eyes hurt a little, as if there was a subliminal flicker. When I look at a similar shade hiding an incandescent bulb, my eyes whisper "Yes," as if the light was nourishing somehow.

is due to a parallel action of blue light in neurotypicals.
posted by jamjam at 10:49 AM on April 22, 2008 [1 favorite]


So why not use a bunch of reds, blues and greens (of varying wavelengths to even out the spectrum)? Put the whole thing in a single package so it seems to be emitting white light and bam, you are done.

Because life isn't that simple and your eyes don't really work like that. Saying that your eyes see "red,green and blue" components is a drastic simplification of reality. They only approximate to that - in fact we sense across the whole spectrum but seem to do some rather complex subtraction of some sensors from others to approximate RGB. It's not possible, for instance, to reproduce the full gamut of visible colours using Red green and blue lights. Viewing things under pure red green and blue spectra isn't the same as viewing under full spectrum illumination and there will be colour artefacts. That said - a lot of lights in my house are LEDs (they aren't much more expensive than normal lights at the local supermarket these days) and I really like the quality of the light - it feels a bit like moonlight. I was going to hypothesise that moonlight might also have an odd spectrum and quickly googled it and came across THIS nerdlicious page which probably deserves a FPP of its own.
posted by silence at 10:56 AM on April 22, 2008 [2 favorites]


ardgedee : I worry about LEDs being oversold. They don't last forever (their brightness slowly dims, and heat exposure shortens their lifespan)

Yeah, but in fairness, most of the new high-output LEDs rate their lifespans in 10,000 hour increments. That's more than a year of constant run time, and when it does reach that point, it still will be capable of producing light, just about half as much. Plus they are far more shock resistant (more useful for portable lights, but still.)

Regarding the heat issue, I know that an increasingly common tactic is to take a higher wattage LED and under-power it to keep the heat down. I don't know if the LED bulbs use this trick, but it's a simple way to keep the heat concerns minimized.

It might not last forever, but it will certainly outlive most incandescents.

(The color spectrum thing is a bit of an issue though. We want to figure out a way to use them on fish tanks in our house and it's been a bit of a chore.)
posted by quin at 11:03 AM on April 22, 2008


silence: it's probably worth pointing out at some point that LED bulbs aren't "more efficient" unless you don't have to heat your house. That "wasted energy" from incandescent bulbs is presumably lost as heat, so it just results in you having to heat your house less.
Best-case, that's a break-even -- if your house uses electric resistance heat. Virtually any other type of heating is more efficient and more cost effective. Its generally cheaper (and more ecologically sound) to get heat from your furnace.
posted by Western Infidels at 11:10 AM on April 22, 2008 [1 favorite]


For extra fun the madman that owned our house before us was a big fan of halogen lamps, lots of them, in recessed fixtures in the ceiling. They put out a LOT of heat. I tried replacing them with CFLs, the dimmable kind because all of this is on a dimmer (a dimmer that also heats up a lot), and the CFLs flickered and died. So now it's back to the halogens. i guess I could replaced them with regular incandesants, but that doesn't seem like much of a step forwards. I have a suspicion that everything needs to be ripped out and replaced in a very expensive way.

Our plumbing had some similar innovations that required expensive replacement. oral of the story: never buy a house from an engineer who likes "doing things himself".
posted by Artw at 11:19 AM on April 22, 2008


Artw - where i live (in france) you can get drop-in LED replacements for halogens in most supermarkets. They're the same form factor - you just replace the halogen bulb with LED ones (there are varieties for both low voltage and mains voltage). The main issue is that the LEDs tend to be a lot less bright than the halogens, but whether that's acceptable or not depends on what you're using them for. I've seen them in supermarkets in Holland and other places too, so I suspect you can find them pretty easily.
posted by silence at 11:32 AM on April 22, 2008 [1 favorite]


How do LEDs do with dimmers? I suspect that the switch just varies the resistance using some kind of coil (which, as i've mentioned, gets quite hot).
posted by Artw at 11:34 AM on April 22, 2008


As fun as it is to get everyone to Buy New Things, especially disposable things with mercury in them, I'd like to see at least as much energy put towards, for instance, making light shelves and similar innovations an assumed part of any building project or retrofit. Conserving energy's good; not needing energy in the first place is a lot better.
posted by regicide is good for you at 11:37 AM on April 22, 2008 [1 favorite]


Artw most dimmers turn the bulb on and off very quickly. Whether it works with LEDs or not depends basically on how fast it does this pulsing. If it's too slow it will be unpleasant. LED drivers designed for the job operate thousands of times a second so the flickering is imperceptible. It's possible if yours were designed for halogens they might be quite slow, but you would have to research the exact type of dimmer to find out.
posted by silence at 11:46 AM on April 22, 2008


I'll probbaly buy an LED light as a test case, to see how it works. I've a suspicion that, because as I've said my h ouse has had it's electrics operated on by a mad man who was into doing things on the cheap, the little sliders that operate the dimmer might not be doing the pulsing thing and might just be changing resistance. Would the heating of the dimmer switch be normal if it used the pulsing?
posted by Artw at 11:48 AM on April 22, 2008


I use CFLs in hard-to-reach spots (I've not yet had one burn out) and almost-always-on fixtures (the light in the hallway). The cheapo ones make me want to scratch my eyes out, but the "warm" variety from Home Depot are actually OK. I don't use them in places where I read or write though. I should point out that my office has old-school tube fluorescents, which are dreadful, but I also get a lot of natural light, so that mitigates that awfulness.

So: Sun>>Incandescent>CFL>>Tube fluorescent>being poked with a stick
posted by Mister_A at 11:48 AM on April 22, 2008


(Wow, I've just derailed the blue into something that would probably sit better on the green - that's a first)
posted by Artw at 11:49 AM on April 22, 2008


Silence: I was going to hypothesise that moonlight might also have an odd spectrum... and then I thought about it for a minute and realized that the moon is a reflector, not an emitter. :-)

The other strange but in retrospect obvious thing about moonlight is that when taking a picture of the moon itself, you have to meter for an object in full daylight. Which, of course, the moon is. That's why it's so difficult to get a picture of the moon and anything else at the same time.

On CFLs: I've replaced most of my bulbs with them, as they've burned out. They have a noticeable warm-up period, which takes getting used to. The light is not the same as incandescents. But for the most part, I'm happy with them.

I just did a lot of work on my house, and installed three recessed fixtures. I chose fluorescents for those -- the ballast is in the fixture itself, they don't take regular screw-in CFLs. They work very well, and use a lot less energy than comparable incandescents or halogens.
posted by rusty at 11:51 AM on April 22, 2008 [1 favorite]


Silence - Really? I thought that was how mosfets worked. Last time I looked it up, everywhere was suggesting dimmers worked by clipping the AC waveform.

In the UK at least, dimmers don't work with CFL or LED lights. CFL flicker or don't come on. LED stay lit until you get most of the way down the dimmer, and then they just turn off.

In fact... Ask Mefi...
posted by twine42 at 11:57 AM on April 22, 2008 [1 favorite]


How do LEDs do with dimmers?

Depends on the driver -- most LED drivers have enough capacitance so that the LEDs would either be on or off. If the driver ended up switching with the dimmer, your LED would blink at the chopper rate of the dimmer -- which would drive you nuts, because LEDs switch on and off so fast (no glowing hot filament to cool down.)

This is the way you dim LEDs -- by turning them on and off rapidly, with more off for dimmer light, but you need to switch them much faster than an incandescent.

The problem with LEDs is twofold.

1) Very small light source, almost a point source (effectively so from any distance.) Thus, shadows are very hard. Arrays of them end up being even stranger looking, you have multiple points sources.

2) Those very small light sources can generate a lot of heat -- and because they're so small, getting the heat away from the LED before it fails is becoming a very untrivial problem as the power density increases -- plus, you need to have as much of the LED open to air so that it can emit light.

3) They're just not that bright. Even the stunningly bright ones are still hitting only a 100 lumens -- and they only emit in a cone, around 110-140 degrees. (Arguably, they shouldn't be rated in lumens, they should be rated in candela, which has an area component.)

There have been demonstrations -- a Osram Opto 6 LED cluster, drawing 22W, put out 1000 lumens. Impressive, but my 23W CFL puts out 1600W. At lower power draws, the heat was easier to deal with and the efficiency -- lumens/watt, got quite high -- but then it was only putting out 300 lumens.

I think LEDs might never really become useful area lighting lamps. I could be wrong, but I suspect that other technologies will be the replacement for incandescents. The hardest thing to deal with is the energy density and heat density issues -- those LED dies are very small, so even leaking a a tenth-watt or two as heat means real problems, never mind a full watt.
posted by eriko at 11:58 AM on April 22, 2008 [2 favorites]


Good linkage!

Hmm. Looks like I'm probably sticking with what I've got until I can rip the whole thing out :(
posted by Artw at 12:01 PM on April 22, 2008


twine42 I'm happy to defer to your greater knowledge of mains lighting dimmers - I'm sure you're probably right. However, I just checked out the "lutron" dimmers that have been mentioned on this page and from what it says there it seems they use a kind of cheap and nasty form of pulse width modulation .

"This dimmer component actually turns light on and off very rapidly - 120 times per second."

Looking at their diagram it doesn't seem to actually 'clip' the waveform (like the dimmers you mention) - it seems to do something more like gateing it. But - to finally answer Artw's question 120hz is going to be nowhere near fast enough to stop an LED looking flickery - so don't do it.
posted by silence at 12:21 PM on April 22, 2008


I replaced all the bulbs in my old house with the more expensive kinds of fluorescent bulbs that produce a more "incandescent" color, the cheap ones are too blue/purple incolor and have bad flickering problems. I still prefer a 60 w incandescent bulb for reading lights in lamps and that kind of thing, but it was a good move for three very important reasons. I also do it in the apartment now and it is a lot better.

First, and obviously, I saved a lot of money on the power bill moving from 100 W bulbs to 15 W bulbs considering I had probably 40 different bulbs in the house. They aren't quite as bright

My neighborhood power is funky because my regular bulbs never last more than a couple of months, I would literally go through 12 bulbs in 2 months. Some of my fixtures have to be removed from the wall before the bulb can be replaced and some are hard to reach so it was a big improvement there.

During the summer it made the house a lot cooler because it was a fairly large house that was hard to cool because of its long winding shape. We also only had swamp coolers because it is the dry desert here and they are decently effective and a lot cheaper than A/C, but it takes longer to cool a house. CFL and LED produce a lot less heat so are better in this situation.

New Efficient plasma light bulbs that could replace halogens and others. This might be an interesting new alternative to both CFL and LED.
posted by hellslinger at 12:37 PM on April 22, 2008


Good quality CFLs have better colour, but even with crummy ones -- gosh it's nice to not be replacing bulbs around the house every month.

As for future lighting, I think EL panels will be lovely. Just make my whole ceiling light up, please.
posted by seanmpuckett at 12:44 PM on April 22, 2008


I'm replacing all my bulbs with ROTFLs.
posted by Pollomacho at 12:49 PM on April 22, 2008


> Even the stunningly bright ones are still hitting only a 100 lumens -- and they only emit in a cone, around 110-140 degrees.

I'm seeing up to 190 lumen for some Luxeon LEDs. But otherwise I agree with the point of your argument.
posted by ardgedee at 12:50 PM on April 22, 2008


I get how CFLs are more efficient and all. But I hate my house feeling like a convenience store. It's almost impossible to use dark surfaces, especially deeper paints. I red-did my parents' office with a medium-ish green and dark wood floors, and with CFLs in the 6 recessed ceiling fixtures, it looked like a morgue. Replaced the CFLs with normal 60w bulbs and dimmer switch, and even at half-lit, they just murder the CFLs and add a warmth to the room that CFLs never would.
posted by ninjew at 12:52 PM on April 22, 2008


We have two main overhead fixtures downstairs in our home office, and each takes two bulbs - we put a regular CFL and a so-called daylight spectrum CFL in each fixture and that seems to produce the right blend.
posted by Zinger at 1:11 PM on April 22, 2008


Eriko, fascinating stuff. My enthusiasm for LEDs has dimmed (pun intended), but wow! You are one smart cookie!
posted by Mister_A at 1:32 PM on April 22, 2008


Jesus, that plasma bulb looks like magic. Hope that tech is made home-usable.
posted by lumpenprole at 1:34 PM on April 22, 2008


59 comments and no one mentioned that CFLs screw in just like incandescents?
posted by Big_B at 3:44 PM on April 22, 2008


Fuck it, I'm going laser.
posted by Artw at 4:03 PM on April 22, 2008 [1 favorite]


I'm seeing up to 190 lumen for some Luxeon LEDs

Could be, haven't looked at a recent spec sheet -- but I was talking white LEDs. Of course, maybe they have 190 lumen whites now.

I know they have 200 lumens in Red, but if you hate CFLs for the color rendition, red LEDs are really going to piss you off.
posted by eriko at 4:13 PM on April 22, 2008


psst! psmealey, there's a misspelling in your tags! It's causing a buzz behind my eyes!
posted by flapjax at midnite at 4:42 PM on April 22, 2008


eriko: I have an LED lightbulb, a Lemnis Pharox, in a table lamp. The box it arrived in says the bulb puts out 230 lumens.

The light output is a little weak (feels like a 25W or 30W). I don't have any CFLs with which to compare light quality, but next to an incandescent, the bulb's light doesn't have much of that yellow/warm emphasis. All that said, it's Not Bad, and if a 400-500 lumen bulb comes out, I'll try it.

The box also says the bulb is rated for 50,000 hours and puts out 4W. I tend to switch on the lamp for about 6 to 8 hours a day. I'll keep an eye on whether its brightness declines over the next year or two.
posted by Jubal Kessler at 5:02 PM on April 22, 2008


eriko: on review, I think you were probably referring to single LEDs. The Lemnis website has a video of a news segment that includes a cutaway of the bulb, and my recollection is it's a cluster of four or five LEDs.

So I imagine each LED doesn't put out 230 lumens. The bulb casing is opaque and diffuses the light pretty well, so I'm wondering if the 230-lumen measurement is for the light measured with the casing on rather than per LED.
posted by Jubal Kessler at 5:08 PM on April 22, 2008


We switched to CFLs some time ago with no problems but one -- the pause before lighting creates a real hazard when you use it as a stair light, since the habit is to flick and step... well before the thing turns on.
posted by Durn Bronzefist at 5:38 PM on April 22, 2008


> Plus, CFLs do contain mercury, which is a concern to me, in that their end-of-life requires either special disposal or specialized recycling.

Which, of course, they're not getting. With Walmart pushing CFLs massively to Walmart's customer base? Most people just toss dead ones in the trash and they go straight to the landfill.

Frankly I like harsh alien sterile blue light--makes the velocity ghosts easier to see. I have no incandescents left in my house, they're all fluorescent and I specially look for the 6500K jobbies for everywhere except the bathroom mirror where there are two 6500s and two 5000s. But I really hope this turns out to be merely a somewhat ill-considered rush to an oversold new technology and not an actual disaster, with the Superfund people having to buy up landfills all over the country and shut them down over mercury contamination. I get my MDR of mercury in my tunafish, thanks.
posted by jfuller at 5:51 PM on April 22, 2008


When we remodeled our Florida house last year we installed a bunch of recessed can lights in the ceiling, there are about 20 in all on 5 circuits. We installed CFL's and they have worked great. There is a slight delay when you turn the switch on but we have gotten used to it. I tried some LEDs but my better half absolutely hated the color. The coolest thing we did, was install this stuff under the kitchen cabinets over the counter and sink. It's way bright, really efficient and instant on. We also installed some in different colors on different circuits above the cabinets as a ceiling wash and it gives off a pretty cool "Austin Powers Groovy Baby" kind of glow. We just added these to our rental stock for our business and they use the latest tricolor LEDs, everybody who has used them raves about them. Hopefully the technology will become more affordable to the home user.
posted by HappyHippo at 9:06 PM on April 22, 2008




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