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Why LEDs Don't Beat CFLs Even Though They Should
TaeKwonDood writes "LEDs don't beat CFLs in the home yet, but it's not simply because PG&E is getting rich making people feel like they are helping the environment buying CFLs made in China that are shipped to the US using a lot more fossil fuels than they save. It's a problem of indication versus illumination. However, some new discoveries are going to change all that."
wat the f are you doing with the lightbulbs?
just my wallet. I got a set of LED GU10 bulbs for the flat because when we got in there were two fittings of 4x50W bulbs each, and with the energy saving from some LED replacements (~£10 for 4 at ~2W ea, normally ~£5ea but i found a deal) easily paid the difference, especially since i was having trouble finding CFL replacemetns. However they definately give off significantly less light than the 50W halogens, which is fine most of the time as i prefer a dimmer light usually, but can be a little frustrating if i find myself needing a little extra to look for something, The light is alot 'whiter' which took a couple of days to get used to but is fine now. They are also very directional, they light up one area very well, but are quite poor outside that area, so fine if you are after light in a particular area (they are often advertised as for lighting up some piece of art you want attention drawn to) but not so good if you want to illuminate a room.
an directionality. It's hard to beat CFLs and moreso some good quality fluorescent tubes get slightly more lumens per watt (although I saved 100 watts per hour in the kitchen - 200 instead of 300- by going with directed CFLs that shine line exactly where needed vs previous central flourescent tubes that were lighting from the center trying to sloppily spill light everywhere).
Since every Home Depot now takes any CFLs, the disposal is actually better than fluorescent tubes. Considering most electricity comes from coal, you prevent mercury release in the air vs incandescents. And no, you don't need a specialized clean up crew if a CFL breaks: http://www.snopes.com/medical/toxins/cfl.asp
Except for the oven, fridge, and flashing lights - CFLs are appropriate for most applications.
I would love to have LEDs. But they need to raise their efficiency. They don't generate heat as such, but AC->DC conversion does, index of refraction of the casing material presents a problem, as well that leds don't generate white light by themselves (they use phosphor?) and all that reduces the light given off.
It would be cool if those were solved one day, where they got near 90% theoretical max lumens/wax (683 lm/wt), where a 3 watt LED would give off the same light as a ~100 watt incandescent or ~23 watt CFL. Even 150 or 200 lm/wt would be a revolution. But it will take 5-10 years I suppose.
Because TFA is unavailable, I'll simply say that I replaced all CFLs in my house with regular light bulbs. The CFLs that didn't overheat and scorch the fixture dimmed dramatically in the first year (first and second generation). Even if they performed as advertised and didn't spew mercury, the cost to get in is not recovered by the power savings. I'm no longer an early adopter and the wifey loves her 200 watt light in the laundry room. Also, without the startup delay of CFLs the first step down to the basement no longer is an Indiana Jones leap of faith. I'm waiting for LEDs and by the time TFA is available they will be a generation better.
Better than MagLite:
http://www.surefire.com/
One of the big things I love about Surefire is the amount of engineering that goes into their products to make them as good, and as tough, as possible.
They even point out that while other flashlights have a higher candlepower rating, that candlepower is a flawed system of measurement and they're higher on the lumen scale (looking at intensity vs frequency, candlepower is proportional to the max value, and the lumen rating is related to the area under the curve). I love any company that's that committed to actual engineering of their products.
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I've heard that a room lit by LED doesn't look as natural, but then again, I haven't seen LED light fixtures to test for myself.
http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
Sounds about right. We seem to have to replace 6 CFLs for every one incandescent bulb. Any of the non-standard ones seem to be far worse (a dimmable CFL died after less than a day while not even dimmed, a couple of flood-style CFLs are on their way out after only a few months) but the marketing on 5-10x the lifetime of a standard incandescent bulb couldn't be more wrong.
I don't buy the mercury arguments and prefer CFLs for other reasons (I can actually get cool white and daylight bulbs, for one), but my experiences so far definitely give incandescents the win for lifespan. The fact that our electricity bill seems to be RISING as we switch bulbs over to CFLs is probably a separate issue, but we're sure as hell not seeing any energy savings either.
As for shipping, CFLs are quite a bit heavier than a twisted tungsten wire, so shipping a container of CFLs the same distance as a container of incandescent bulbs could well cost more too.
How are sites slashdotted when nobody reads TFAs?
The vast majority of light bulbs are imported from China. Incandescent, halogen, fluorescent, CFL, you name it, it's likely made in China. I own a hardware store and have watched over the years as production of GE bulbs has shifted from the US to Mexico to China. It was interesting to note that some of the specialty bulbs (for example, a bulb called Lumiline) had very high defective return rates when produced in Mexico, so GE moved manufacturing back to the US for a while until the bugs were worked out.
Anyway, this transportation cost objection is bogus IMHO. Incandescents weigh slightly less than CFL's, but they take as much "cube" space in container loads so the cost to transport is probably similar to CFL's.
"We make our world significant by the courage of our questions and by the depth of our answers." Carl Sagan
>Or until government regulates incandescent out of existence.
Which many of us hope will not happen. There is no suitable replacement for incandescent in MANY applications. My house has many such.
Flor is generally not dimable. Even those that claim to be really are barely and cost a fortune.
Flor saves NO MONEY when dimmed, even if you can find expensive dimable ones.
Flor bulbs do not fit in all fixtures, especially decorative ones and small ones.
Flor bulbs are UGLY in many types of fixtures, period.
Flor FIXTURES are UGLY in many types of applications.
Flor light is not pleasing to many people- it is too white/blue or harsh.
Flor fixtures often emit lots of RFI.
Flor fixtures often emit noise.
Flor lamps are not instantly on.
Flor lamps are also not instantly 100% bright, many taking MINUTES to reach full brightness.
Until you can address all or most of those issues, there are very valid reasons to prefer incandescent lighting in many situations. I, for one, have replaced about 1/3 of all my lights with flor, but the remaining can't be because of many or all of the above reasons. If anything, tax incandescent lamps to make them cost parity with alternatives, but do not attempt to eliminate MY CHOICE until there is a truly suitable replacement.
Disclaimer: I have no experience with LED "lightbulbs" like those in TFA, only LED flashlights
To me, the biggest hangup on going to LED lighting from CFLs would be the spectral issue. In my experience, "white" LEDs don't actually put out true white light, but rather several distinct wavelengths that look approximately white to human eyes. IIRC they lose some definition with red/green. Not as big an issue for a flashlight, but in room lighting I'd kind of want all the colors showing up. This may very well be solved by now, however. I don't know.
The meek may inherit the earth, but the strong shall take the stars.
The assumption was that the incandescent bulb was made in the US and the CFL was made in China. Therefore the extra fuel is incurred once in the life of the CFL.
Your point is good that, if a CFL lasts 8 times longer, you must make 8 incandescent bulbs, which consumes some amount of energy.
Just call them "Gucci designer LED's" or some such and stupid rich people will buy them by the thousands and the price will drop.
"I'd rather have a bottle in front of me than have to have a frontal lobotomy."
I've seen similar issues with specific outlets in my house. CFLs last about 2 months and incancesdents a year or two. The problem appears to be fluctuating power supplies. Our house's power isn't very stable... the vacuum cleaner, dryer, and other devices cause lights to slightly dim or flicker. I've solved most of it by separating the circuits, but the CFLs seem to be VERY sensitive to fluctuating electricity.
A CFL on its own circuit seems to last a long time.
E pluribus unum
sick of them.
They also need to make Led's smaller so we can have LED TV's.
I really want to switch to LEDs. I've become disillusioned with CFLs in recent years. The very first two CFLs we ever purchased, in the mid-nineties, -- my wife's reading lamp and the hard-to-reach light in the stairwell -- are still working. But in recent years (since maybe 2002) I've had a remarkable number of failures, often in the first month of use, and I rarely see more than a couple years of service. Oddly enough, I get longer service from the outside lights, which should be the harshest environment. The indoor CFL overhead lights (except for that stairwell light) last about a year. The worst service is from the CFL globe lights over the mirrors in the two bathrooms. I lose about one a month, and recently I've started replacing them with incandescents as they burn out.
I think part of this is due to putting CFLs in environments where they do not thrive -- anywhere you have heavy on/off duty cycles like a bathroom or occasionally used overhead. But I wonder also if CFLs in general haven't become (at least in part) victim to "value engineering", IE, making them as cheap as possible.
But anyway, what worries me about LEDs is that although they *should* give longer life, (50K hours vs 15K for CFL and 1K for incandescents) they apparently don't, judging by the LED array stoplights that have been put in all around the city. It's difficult to find one that doesn't have large parts of the array completely out or blinking madly. Around Christmas I noticed that some of them had been replaced with conventional bulbs. Looking at the technology, LEDs should do better, but it's all about implementation.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
I've been using CFL's since at least 1995, probably a lot earlier. Starting with the big Philips 'jam jar' types which lasted more or less forever - I still have some of the first lamps I bought, now more than 15 years old, they still work - and gradually moving to the more recent folded tube and even more recent incandescent form factor ones I have yet to see any trouble with them. They *just work*, save a *lot* of power and hardly ever burn out.
In other words, I completely fail to grasp the reluctance to change over, leading even to conspiracy theories and pseudo-science arguments against these dependable light sources. They may not be the best choice for all applications but they are a good match for most.
--frank[at]unternet.org
That is why they are great in torches, head lamps, and backlights - because you don't need complex optics to focus the light. White LEDs are still quite expensive though, so bulb made out of it would be a lot more expensive than a standard one.
The little snippet at the end of the post if off-base, but it is good to keep in mind that LEDs are significantly more environmentally friendly nonetheless. They last a long time, years and years, and they are very durable. They don't require toxic chemicals, and they are more energy efficient than CFLs.
It's actually harder than it seems. Just imagine trying to light up a room using a laser. How hard can it be, right? LEDs are *very* directional too.
It takes far more than a simple lens, or a simple reflector to manage to illuminate a workspace evenly using them. Reflectors work fine for incandescent/fluorescent and such non-directional light sources.
That's why we see LEDs thrive in many applications like flashlights and traffic lights and not others: those require directional light.
And even if you found a great way to do it, it would still add [likely significant] cost, and likely a fair amount of weight, if using optics. It would probably look like a huge catadioptric lens of a lighthouse (well, the inverse job, but a huge chunk of glass is what I meant). The best I've seen so far, is using a large number of lesser power LEDs...
The energy payback is within the first hour of use.
I figure you can fit in ~300000 CFL bulbs in a container.
http://www.google.com/search?q=12022mm+*+2352+mm+*+2395+mm+%2F+(1.7in+*+1.7in+*+4.4in)&btnG=Search
Wikipedia says it takes 85MW to bring a certain class of container ship up to speed.
http://en.wikipedia.org/wiki/Container_ship
Which works out to 1/50th of a watt per bulb. Thats such a small number, trying to calculate the cruising energy seems fruitless...
http://www.google.com/search?q=85MW+%2F+14000+%2F+300000
The experiance of everyone I know who has tried LED light fixtures is they simply don't have the ability to decently light a room (whether this is due to thier being simply less light output or whether it is some other characteristic of the light I don't know) while CFLs do. They are also FAR more expensive than CFLs.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Flor is generally not dimable. Even those that claim to be really are barely and cost a fortune.
...
My dimmable floods don't get quite as dim but they go from about 8W-100W equivalent. They cost a couple bucks a piece.
Flor saves NO MONEY when dimmed, even if you can find expensive dimable ones.
Huh? The switching power supply in good ones are perfectly capable of using the rated wattage which is way less than the equivalent incandescent.
Flor bulbs do not fit in all fixtures, especially decorative ones and small ones.
True enough, LED's will rule here.
Flor bulbs are UGLY in many types of fixtures, period.
How many fixtures do you have with exposed bulbs anyways?
Flor FIXTURES are UGLY in many types of applications.
Flor light is not pleasing to many people- it is too white/blue or harsh.
You can get them in just about any colour you want and better manufacturers have CRI's from 82-95, though you will pay a premium for anything &RT90.
Flor fixtures often emit lots of RFI.
Buy non-crappy ones.
Flor fixtures often emit noise.
Buy something not sold in China town.
Flor lamps are not instantly on.
My GE bulbs are on in about a second.
Flor lamps are also not instantly 100% bright, many taking MINUTES to reach full brightness.
Peak brightness is about 10-20 seconds depending on ambient temps.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
For about a year now, my home office has been lit with LEDs. I have 3 watt units on goosenecks that I switch on and twist for directed illumination, and arrays of RGB units that have tunable color. They all feed through the UPS that protects my desktop, and consumes, at most, a little over twelve watts (when all lights are on and RGBs are set to white light). I'm quite happy with the effect and level of illumination. The only downside is that the rest of the room is relatively dim, lit only with reflected light that spills from the desk, but remember, some lights are on goosenecks, so when I need light across the room, I just twist them to face that direction. If I need more light, then I switch on a single CFL for a few minutes until I'm done.
I buy these bulbs, at about $1.25 per. Their color temperature seems closest to true daylight to me, and I've tried almost all of the different bulbs marketed as such. I hate the orange-ish glow of the "normal" bulbs now, and hate all of the CFLs' color I've tried too.
No offence to the people at Purdue, but they're not even close to leading edge on this. Bluglass ( http://www.bluglass.com.au/) in Australia have commericalised gallium-nitride substrate, which can be produced _at room temp_ (not the 400-600 deg C required by sapphire), and as a bonus results in high-brightness LEDs to boot! This stuff is light years ahead of the material in the OP's story, both in technique and delivery to market ... you can buy a black box fab from Bluglass now :-) and start churning out your domestic LED "bulbs" to bump off CFL (sorry, could resist the light-year joke)
Thanks. Some actual information is way more helpful than the vague claims swirling about. I thought about trying to figure out where bulbs are being produced, but didn't have a lot of luck with the Google.
The projectors my school uses seem to follow the razor business model. $20 projector, $50-70 nonstandard bulb. Unlikely that company would switch to something that lasts longer. Unless they move to a completely closed unit (no replacing the bulb/fan/power supply).
I don't preview or spellcheck.
Sounds about right. We seem to have to replace 6 CFLs for every one incandescent bulb.
I think you may have a problem with your light switches, if your CFLs are lasting such a short time.
Something to remember about CFLs is that their life is drained by switching them on and off much moreso than for incandescents. On the other hand, incandescents' life is drained by keeping them on much moreso than for CFLs.
I had an experience where when we installed a CFL in a particular socket, the corresponding switch was faulty(it would not go all the way up or down unless you pushed it harder than normal), causing the CFL to flicker very quickly. That CFL lasted a few months, I think. Then, we installed a new switch, put a new CFL in there, and haven't had a problem since(a year so far).
You may have a similar issue, or a faulty source of bulbs.
Knowledge is just opinion that you trust enough to act upon. -Orson Scott Card
For something more compact [...]: a diffraction grating. Add a glass frosting on top of a couple of layered diffraction gratings to make the light more evenly diffuse.
A similarly simple/cheap solution would be to use a non-perfect parabola or convex mirror. The LED beam, though directed, is not infinitely thin. Therefore, putting it at the "focal" point of a shiny, non-perfectly parabolic surface or aiming it towards a matte convex mirror would also do the trick.
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So-called white LED spectra are produced just like the spectra of fluorescent bulbs: white LEDs are actually UV LEDs that illuminate phosphors with different inherent spectra to cover the visible range.
For a brief while, triplet R/G/B LEDs were put in one package, but those are (a) too expensive, and (b) suffer from dramatic white-point shift (color shift) as the three chips age differentially.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
You are either buying CFLs from a completely incompetent manufacturer, or simply have a bizarre situation where reality is bending around you.
Or he's compulsive about turning off lights when he walks out of a room for two seconds. CFLs don't like to be switched many times, so they're great in a living room where you tend to turn them one once at the beginning of the evening but maybe not so much in a frequently-used bathroom.
Dewey, what part of this looks like authorities should be involved?
Actually, try Dec 23rd-24th. I got some for 75% off. Not many people still putting up decorations that close to the holiday.