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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."
LEDs are not traditionally used for illumination not only because of the costs of LEDs, but because of the complex optics required to distribute the light. it's rare to see LEDs used for illumination, though it is making an entrance for some applications, like flashlights and even headlamps. As LED prices continue to come down and LED optics technology improves and cost stabilize, conventional LED lamp retrofits will become commonplace. Take a look at LEDtronics for some examples.
I've had nothing but frustrating trying to find an LED bulb that my partner won't moan about being all cold, dim, too bright, or all three. Me, I don't give a sh*t as long as I can see my toes.
The sooner these "new discoveries" filter down, the better if you ask me.
"And the meaning of words; when they cease to function; when will it start worrying you?"
CFLs made in China that are shipped to the US [use] a lot more fossil fuels than they save.
'Cause incandescents are all made in the US and don't share nearly the same shipping costs.
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
I have access to all kinds of LEDs, straight from a fairly large distributor, lots of high-end stuff and what not.
I work in electronics, so I'm more than able to design and build whatever circuit to power them in any way I please.
The only problem here is LEDs emit directional light. And there are no easy ways to "diffuse" the light...
Errr... could we have some actual numbers for that? Are we seriously asked to believe that the energy saved by a metric ton of CFLs over their lifetime is less than the cost of a one-trip transport on a freighter? Or is that just another bitter remark aimed at those silly little hippies who want to save their pwecious planet and their breathable atmosphere and their clean water?
-- Language is a virus from outer space.
Just like every other thing.
wat the f are you doing with the lightbulbs?
You're seriously trying to claim that the savings of CFLs are offset by shipment? Really?
I would go into the obvious math or the economics, but honestly this is just simply too stupid to even deserve further comment, except that it is a completely asinine, baseless statement that I'm sure will be picked up and repeated by a lot of ignorant contrarians.
They come in two color temps. "Cool White" is about the same as a white LED. Sterile and way too much blue/green. "Warm" is another name for sickly yellow and makes me think of those yellow incandescent bulbs used to keep moths away. Until they make a CFL that matches a normal incandescent I'm not switching.
Only the State obtains its revenue by coercion. - Murray Rothbard
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.
They were being used a diffuse eight-color lights composed of about 50 LEDs of the three primary colors. Probably saves a bundle on electricity and air conditioning. not as spotlight yet.
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.
Also consider the fact that stuff made in China does significantly more damage. They have little or no pollution control and are quickly poisoning the Earth, the workers are basically slave labor in poor conditions, etc.
The assertion that the cost of the emitter (LED) is the limiting factor, is just as laughable now as it was the first time this article was posted.
The run-on sentence in the blurb certainly doesn't help matters.
I did not against the idea that we need to protect our environment.
I against that people did not use their brain on this. People take the idea as if and retold the story without thinking.
Now that Environment Protection or GREEN have been GREENISM which were eating intelligent as food and turn out to be our biggest nightmare.
Why there are no legislation that people only can drink water instead of sodia is just time. Why we allow such laws pass is signal of a very ill society.
Using more money to go GREEN is against my common sense. STOP that, use our brain, do things correctly, not just follow others.
When the whole world think the same, terrible things happen.
Use your brian, please.
i bet they have a vested interest in selling those CFL lights, i bet they own stock in them or something along those lines...
Politics is Treachery, Religion is Brainwashing
China is the Western world's factory exactly because they have no pollution control and slave labor. If they set more rigorous standards for worker's rights and the environment, we would manufacture things in the cheapest country somewhere else.
Wow. Way to sneak in that lie under the radar. Politically motivated, or just simple ignorance?
In any case, no, the manufacturing and transport of CFL bulbs absolutely does not generate more CO2 than that saved by using them (assuming coal/natural gas powered, the only logical comparison in this case). Let's run some simple numbers.
Assuming an average 60-watt equivalent (12 watt nominal) CFL bulb with a lifespan of 10,000 hours, it will draw 120kWh over the course of its life. The 60-watt incandescent, if it lasted as long, would draw 600kWh. Of course, it doesn't last as long, but rather an average of 1/5 as long.
So the savings are roughly 480kWh for an 800lm fixture. That's the equivalent of over 400 liters of gasoline burned in an internal combustion engine, and that doesn't include the fuel used building, shipping and shopping for replacement incandencents, which as mentioned burn out far more frequently.
Now for some logic. How is it that a bulb which apparently requires >480kWh of energy to build/ship ($48 at $0.10/kWh) sells for a few dollars? Hint: it doesn't require >480kWh of energy to build/ship, or anywhere near that.
CFLs offer a massive net efficiency gain, and by extension, a net reduction in CO2 emissions. Even factoring in disposal costs at 5 times the manufacturing cost (silly), CFLs are a net win. So please don't spread that tripe!
A government is a body of people notably ungoverned - AC
If a 25W CFL replaces a 100W incandescent bulb, and the CFL lasts 8000 hours, it will save 600 KWHrs of energy. .11 gallons of diesel for the journey. That is about 6 KWHrs of energy.
If a shipping vessel can hold 35,000 tons of cargo and the shipping weight of a CFL is 1/2 pound, the vessel can hold 140 million bulbs. Of course there is not enough space for them all, but they can ship with heavier items, and I am assuming costs are allocated by weight.
If a 7,000 mile journey burns 875 tons of fuel, or 15.75 million gallons, then each bulb is allocated
Therefore, the shipping costs don't even come close to negating the energy savings.
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
Not to mention that they would cost a lot more if this were actually true. A little research reveals that shipping costs for a 4-pack of CFLs is much less than $1USD, and more like $0.05 to $0.25. That's pennies per bulb, and fuel costs are a fraction of that amount.
Since I expect to save $20-40 per bulb in electricity, I think that it is unlikely that more fuel is consumed in shipping over the life of the bulb.
John
Don't forget that compact CFL put out a ton of UV light that will fade anything in the house that isn't automotive rated. Just look around the room and visualize the room was outdoors in the sun for a year and that fade you will get using CFL. Artwork hanging on the wall will get the most damaged.
They have little or no pollution control and are quickly poisoning the Earth
Yeah, but I don't have to LIVE in China, so it's not MY earth, therefore I don't have to care.
Now bring me the remote and something edible wrapped in bacon!
Nothing worthwhile ever happens before noon
And who is to say that when/if the demand for these LEDs goes up it won't simply be these that are being imported from China.
Hmmm...
Container ships now carry up to 15,000 TEU (approximately equivalent to 35 100-car double-stack intermodal freight trains) on a voyage.
Since the distance from China to the US West Coast is roughly 6000 miles, a cargo ship fill-up would have set you back at least $8.5 million bucks in April 2008. How much fuel does a container ship burn?
It strikes me that shipping a light bulb will cost the about same whether it is incandescent, florescent or LED.
Little practical difference in weight or bulk or fragility.
But you won't making as many runs if the florescent or LED lasts five to ten years.
It also strikes me that 15,000 TEU translates into a hell of a lot of bulbs.
I have had the CFL in my hallway for 15 years.
I haven't changed a lightbulb in at least five, and even that was because somebody hit it with a broom handle. I don't remember much from when I was a kid but those other types of lights would die every now and then.
You're doing it wrong.
It is no longer uncommon to be uncommon.
Oy, where to start?
The current crop of high-flux LEDs are coming in at around 60+ lumens/watt for the LED itself. Once you factor in fixture losses (electrical and optical), you are down to somewhere between 20 and 40 lumens/watt out of the fixture. This is the same efficacy range that CFL fixtures are in currently. And CFLs are a mature technology, while solid-state lighting is not. Metal-halide and linear fluorescent lamps still have higher efficacies, but I would expect LED to approach these technologies over the next 2-3 years.
As far as the color you get out of "white" LEDs, it's not the angry blue-white you used to get and still get in the little 5mm LEDs. The current white high-flux LEDs put out a white light that looks as good or better than a CFL. Remember that white light is a broad, even spectrum of emissions, and you can't get that out of an LED without a phosphor. They've come a long way in the last 7 years (anybody else remember the green-white of the early Luxeons?).
From an optical perspective, LEDs are different from any other light source that is readily available. They approximate a point source very well, but, due to the substrate they are mounted on, are inherently directional. Every other source is omnidirectional, and this makes retrofitting LEDs into traditional fixture designs difficult. So expect LED fixtures to be designed from scratch, and don't expect good LED retrofits for the traditional lightbulbs in the near future.
Cost remains an issue, but it is coming down. You can get undercabinet LED fixtures that compete very well with fluorescent and halogen for as little as $40 at your local home center. And LED light fixtures have been available for niche applications (primarily colored light) for over a decade.
(I work for a manufacturer of LED fixtures)
sick of them.
They also need to make Led's smaller so we can have LED TV's.
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.
Except that commercial shipping is usually done by volume not weight. Only if the weight is extremely excessive does it matter for pricing. Shipping containers are usually charged by the container, not by the weight. They have a weight *limit*, but that is not the same thing. I can't imagine hitting the weight limit of a container with any kind of light bulb.
Trucks are the same way for large quantities.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
I am (would be) all for LEDs, but my honest experience is that they just do not cut it at many places.
One area is dive lights and other flash lights. While batteries last forever with them and they are a good thing as a backup/emergency light, they come nowhere close to a Xenon bulb or a HID light. Nowhere. Whatever the watts, lumen and other specs say, they are just not there.
I also have to agree with the dim/cold comment. Most of them are just emitting this hideous blue light which I do not want to sit in at my home. I use a combination of low-voltage halogen lights and fluorescent lights at the home, and when buying the fluorescent ones I aim for the "sun light/natural light" ones that emit a warm light inside. For the garage and other work areas I prefer the cold fluorescent lights as they are sometimes better to see things in (e.g bike repair in the garage or shirt ironing in the washing room).
For reading/computing environments nothing beats halogen lights: they can be dimmed as needed and they do not flicker. This is an application I imagine led light in actually.
Where else ? Additional lights (supporting a main source) or indicators : directional lights on vehicles, break lights and safety lights, inside lighting. For bikes as "blinkers" front and rear, for motorwikes they could be great for near surface illumination (e.g. a couple mounted on a fork on a dirt bike would give great treal visibility on slow technical sessions where you see NOTHING with a traditional light.
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
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.
I would love to see LEDs make that final leap. But, for the love of god, if someone makes a critical breakthrough please don't sell the intellectual property rights to an existing lightbulb company. Innovations have disappeared before.
The shipping costs are NOT unique to CFLs.
Blar.
A CFLs use 80% less energy than an incandescent bulb whilst produce the same amount of light. Incandescent bulbs are horribly inefficient and produce a huge amount of heat per Watt of light output. I recently calculated that a single 100W light bulb in our house (which is on most of the day), cost us 30Euros to run a year. Just that one light bulb. By replacing it with a (brighter) CFL we saved 24Euro per year! If you are not worried about the environment you should be worried about you wallet. This blatantly factual incorrect article should not be allowed on the front page of slashdot.
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
If it burned a lot more fuel to ship heavy containers, heavy containers would cost more.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
I can't wait until they put LED's into projectors.
My experience has been that the compact flourescent bulbs for a commercial style recessed can light are fine reliability wise whereas the ones that screw into a light socket aren't even worth screwing in due to unreliability. I believe this to be due to the fact that real commercial can lights that take the 24 watt compact tubes use a heavy duty external ballast. It is the ballast that typically fails in CFL's because little tiny components packed into a tiny space by incompetent people are doomed to failure. Some folks on another group have taken apart and analyzed the ballasts and it is not encouraging and potentially dangerous.
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.
LEDs only work in one direction because it's a diode. If you put it to a AC circuit it would only be illuminated during half the cycle. Use two in opposite directions and you can have light during both halfs of the cycle. AC->DC is not required.
Those truly concerned about the environment should be wary of the how improper disposal of CFLs will affect the environment. Also CFLs can't be significantly dimmed (like incandescents and LEDs) without making a horrid buzzing noise. If you buy the hype of the CFL, you are dooming us all to a dull world similar to the office in Joe vs The Volcano.
Let's say that you do pay extra for the incandescent light bulb made in the US. Let's further assume that number of times a user has to drive to the store and replace the incandescent light bulb is compensated by the increased mass, and chemicals, in the CFL. Even with that, one can't ignore the basic physics. A basic CFL uses at least 40 watts less than an equivelent incandescent. Most of that excess power is converted to heat. Unless one lives in a cave, or in a cold region, that heat needs to be removed, usually at a lower efficiency. Generally speaking then, that 40 watts results in an excess of at least 100 watts of inefficiency. This 100 watts, over the lifetime of the bulb, say 1200 hours, or 4.32 Msec, results in an inefficiency of more than 0.4 TerraJoules. A gallon of gas is around .1 megajoules. If it takes 4 gallons of gas to transport a single CFL from the factory in china to your local store, because I can buy a CFL for $3, about a third of the what four gallons of gas would cost.
This, of course, does not take into account that a CFL will last 8X longer than an incandescent, so we are really talking about 32 gallons of gas, rather than four.
Get real. We live in a changing world. As much I would prefer to ride a horse, or ride a bike, or take the bus, I know that I have to have a car. Change sucks, but there it is. CFL, like fluorescence, will exist. LEDs are providing us with new opportunities. Hopefully, before I die, there will be another new thing that will continue to make life interesting.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
I read the article - what the hell is a CFL, for us lay-people???
In real world usage CFL's do not last as long as incandencents. From a number of years of using them for both indoor and outdoor lighting, I'd agree with a general figure of 2/3 the lifespan of incandencents (though in some specific fixtures I'm seeing lifespans of CFL's much lower than that, like 1/5 the lifespan).
I don't know how that alters your calculations but it's a pretty big difference. I'm going to switch to either LED or back to incandencents because I don't think CFL's are currently worth the much larger cost, which offsets the lower energy used.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Oh, a hallway... one of the most used lights in a house I'm sure.
And the one's in your closets still work too, right?
please consider voting parent to 'insightful', or at least 'interesting'
605413? Yes, it's a prime.
"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"
Last I checked the regular light bulbs come from China as well. You replace them more often than CFLs by a significant amount.
There are a number of reasons to be picky about CFLs, starting with the dodgy off brands and the materials.
I hope LEDs take off. I think they have far more potential in dimmable applications.
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.
I've been using CFL's for about four years, some indoor and some outdoor.
CFL issues:
1) None of the CFL's I have used last as long as the incandescents they replace. One outdoor fixture in particular goes through about three CFL's a year whereas before I used to be able to leave a bulb in a few years.
2) Color is not great.
3) Lumen output is lower, usually too much lower.
4) Dimmable CFL's are hellishly expensive. I miss dimmable lighting, which often I turn low enough that I doubt a CFL would be saving me anything in terms of power usage.
5) I can often hear CFL's as a low background buzzing.
I'm going to switch to LED's for a few selected areas, and back to real lightbulbs for the rest of the place until LED's come down to reasonable levels for general use. CFL's are simply a transitory technology and not a very good one at that.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
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)
If you're looking for a low-UV bulb for an especially sensitive area, try our Saf-T-Gard bulbs.
So there's enough of a problem they make a bulb specifically to address it. Seems like he has a pretty valid point to me, even if UV emissions are not near that of daylight, they can easily still be enough to fade pictures pretty quickly - especially if you are using a dye based home photo printer and not a pigment printer. It will not take long before color shifts can occur even if outright fading takes longer.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
My new daylight CFL lamp damaged my laptop IR sensor.
I use the laptop remote to control my audio player software. One day it stopped working for no reason.
A moth later I replaced the lamp above my TV (on another room) with one similar to the CFL lamp in my bedroom (where I have the laptop), the TV remote control stopped working.
With quick electronics I made a IR meter, guess what? The CFL lamp was emitting IR like crazy.
I replaced my bedroom lamp with the old (warm) CFL but it was too late. The laptop IR sensor was borken.
Now, I have to live with a dead laptop remote. The TV sensor is OK, I guess it didn't have much exposure to the IR light.
For those who like ultimate whiteness light CFL lamps and with a HP dv6xxx laptop,
I REALLY RECOMMEND TO PUT THE LAPTOP AWAY FROM THE LAMP.
Energy usage in my room:
Tube headphone amplifier: ~20W (usually on 6-12hours/day)
Incandescent light: 40W (6-12hours/day)
21" CRT monitor: 130W (6-12hours/day)
6 PCs: ~900W (24/7)
While I could replace the incandescent bulb with a CFL (I don't because I don't like the spectrum), the power I save would be negligible, and I actually would save more power if I stopped participating in BOINC projects.
I went looking for LEDs for a gift for Christmas. I found some very nice fixtures at Lowes but the bright (1 watt/LED) three fixture string did not have its own switch: http://www.lowes.com/lowes/lkn?action=productDetail&productId=283277-82850-29110&lpage=noneUtiliTechatLowe's:3-LightBlackUndercabinet/RopeLight
In the end, I bought a desk lamp for about $25 at Target. There is no way to change the 20 (0.25 Watt) LEDs in the lamp, but they are suppose to last 30,000 hours so I would guess that there will be better lamps around before that one needs to be replaced. For sure, the transformer in the lamp isn't likely to last all that much longer than the LEDs. Perhaps the concept of replaceable light bulb needs to be reconsidered.
At the Museum of American History today, at the (otherwise very good) Edison display, I noticed that the "future" technology section did not mention LEDs at all.
The problem is that although the LED can last 200k hours, the electronics (including AC->DC transformer) don't last that long. The same applies to the ballasts in CFL's, and also for the LCD vs plasma TV argument. Anytime someone quotes lifespans of these things, they are not referring to the limiting factor.
Actually, caving (don't call it spelunking) is one of the areas that modern LEDs have absolutely taken over: the combination of efficiency, durability, longetivity, and small package size have completely replaced incandescent options (e.g., http://www.stenlight.com/)
Old-time carbide lamps still have limited application, mostly in giant caves and/or extremely long & cold expeditions, but Fluorescent has always been far too fragile in terms of packaging to warrant consideration.
It's actually more like two and a half days, according to GE. You need to take into account loading and unloading the boat, shipping from the factory, shipping to the store from the docks, the cost of fighting bad weather, packaging the devices, the cost of stores managing their inventory, et cetera. Which is, you know, not to suggest that 2.5 days is a problem or anything. Still, just so you know, someone who knows this process end to end has cooked up two days nine hours as an average to FooMart in middle america.
Still, thank you for being the first person to actually put effort into debunking this pathetically obvious myth.
StoneCypher is Full of BS
C. Crane's GEOBulb looks very promising in terms of the future of LEDs, but the price is quite painful. I'm personally using some 120-130 lumen candelabra LED bulbs, which delivers close to the light of a 25 watt incandescent.
The LED bulbs are now coming in different color temperatures, so things are progressing.
BTW, not all caves are cold. Generally, the ambient temperature is the year-round-mean of the outside temperature, but depth, geothermal activity, etc can affect this, and then you have extreme cases like the Crystal Cave of Giants, which peaks at around 150F -- too hot for humans to survive for long.
Most white LEDs are pretty poor at rendering color, usually much worse than CFLs. The high efficiency white LEDs usually have a poor color rendering index since they're usually dichromatic, consisting of only two colors of light, yellow and blue. Also, the LED colors often shift with temperature as well.
Wikipedia has a good description of how they work.
I think white LEDs will become a lot more useful for lighting in the future, but they're not quite here yet.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
GE still has their lamp plant in Winchester, OH ( I think Ohio). They closed the other North American lamp plant in St. Louis 3 years ago. My dad was the head mechanical engineer. There is still a specialty bulb plant in Matoon, IL. The rest of bulbs are made in Mexico or China. All GE CFL's are made in China.
May I please have my frontal lobotomy if I bring back the ashtrays?
No, it's just plain deviant. Congratulations.
A little Googling reveals that one of the largest container ships consumes a gallon of fuel every 28 feet, carrying a load of 11000 containers of 1200 cubic feet capacity each. That is going to work out to a fraction of a cent per bulb on a trip from China to Los Angeles or Long Beach.
My new daylight CFL lamp damaged my laptop IR sensor.
What? Everything hot emits IR. Incandescent bulbs emit roughly four times more infrared, than CFL.
I have two 25W CFLs (100W equiv.) in the same room as remotes, televisions, DVD/VCRs, etc. I've never had any problems.
It's one of two things:
A) The switching speed of the CFL voltage booster might've been pulsing infrared at a frequency too high for your sensor, which could've worn it out prematurely. The laptop sensor was trying to receive commands from your CFL bulb - hilarious. This kind of problem can be specific to the type of bulb, since different bulbs will have different booster frequencies. The problem bulb would have to be a very rare specimin (of the ultimate "low flicker", high frequency type).
B) Your laptop was poorly designed, the sensor failing was inevitable. You should fixate on repairing it, not how it failed. Grab a soldering iron and earn some geek credit.
It's in their name.
I blame geof's speakers.
I have some CFLs that ran for 18 hours a day for over 4 years.
They are old...purchased in 2004 or so. I haven't subjected newer ones to such treatment.
Blar.
I am forever puzzled by the recommendations of energy efficient bulbs for home use. Energy doesn't just disappear. If you have an inefficient bulb, most of the energy becomes heat, not light. But, if you are heating your home anyways, that's fine. What you are losing on the "light" bill, you save on the "heating" bill. Of course, in the summer, it may be a problem, and electrical heating may not be efficient, but in the winter if you are running an electrical heater anyways, I cannot understand why expensive efficient bulbs improve anything. Can anybody clarify?
It's simple - photon flux density in an LED is just far inferior to that output by a CFL. Add in inverse law and you know why people prefer fluorescent or HID for growing plants.
Disclaimer: I grow herbs using LEDs. Small ones like thyme and basil are just fine, trying to get anything fruiting is an entirely different story.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Thats definitely per cost, not per watt preventing room lighting. I suspect it is the same as CFL, many manufactures overstate the "equivalent light" factor causing a perception of dimmer. I bought led lights for my aquarium, just the 4 watt night lighting lights up 2 rooms ( not reading wise, but way too bright for a night light, the water diffuses the light nicely)
The directional nature also means to be truly efficient you would want more locations, the lasts (nearly) forever nature would tend to lead to a permanent mount.
So saving the cost of running thicker wires, fixture boxes, fixtures, 5 amp switches, etc should make LED lighting affordable for new houses/additions/remodels fairly soon.
(Especially for warm locations where you pay for all heat sources double, with AirCond)
Mine are good, all GE or other big corp.
They all work great, only one died in that the connector to the power broke on a twist action.
My location is temperate, maybe larger temp variations break em.
Liberty freedom are no1, not dicks in suits.
Many things are also manufactured in malaysia or indonesia, or even philipenes, or vietnam.
Liberty freedom are no1, not dicks in suits.
What the govts want is for local power generation demand to be reduced, even if it costs MORE in oil to ship the CFLs.
Thats just a monetary cost by the consumer thats a one time cost, and there after, its an ongoing lower demand for power. Which the govts like to do because they know they cannot generate more for all those millions of extra immigrants.
Thats the hidden agenda.
"Oh sorry, we want a 20% increase in population for economic benefits to corporates, but we dont want to spend billions in expanding the infrastructure of all cities"
Liberty freedom are no1, not dicks in suits.
but the marketing on 5-10x the lifetime of a standard incandescent bulb couldn't be more wrong.
It actually "is" correct, but only if you leave them both 'on' all the time for comparison. CFL's usually die because the starters burn out. It's the act of 'turning them on' that ages them. I threw 4 Watt CFL into a night-light to replace a 25-watt incandescent. Since 1999, I'm into my 3rd or 4th bulb. I think it was about 2006 when I last replaced it so maybe 20,000 - 30,000 hours for 1 bulb. That's extreme, certainly, but such life with an incandescent would be unlikely.
I still have some bulbs in use that I bought over 10 years ago when I converted to CFL's. I went around with a light meter to make sure I had same or better lighting. I found that 'daylight' balanced bulbs were better for color but worse for reading (you'd need higher wattage to provide equivalent reading brightness). I didn't find that CFL's were 25-33% of the electricity (as their labeling would suggest), but more in the 30-40% range.
So you can't claim CFL's are heavier per hours of illumination. So any claim that CFL's are heavier would have to be measured at them having longer lifespans on the average. But you need to use them appropriately -- if you put them where they are going to be turned off and on alot, they will burn out faster.
LED's still cost more and are not as avaiable as CFL. If CFL's are cheaper or on par and you can buy them at WalMart then they will sell better. Until then, CFL's are king.
It's only gay if balls are touching.
That's great for you - I'm glad you like CFL lights.
But now Congress is mandating that I must like them... and that is a problem. I have tried 7 different brands - none of them work. The first 4 brands simply burned out within a month. The next three have lasted a year so far, but the initial light output is so low that the light is useless and my wife complains - so I will not be buying any more, of course.
Honestly, I'd pay $50 a bulb if it really did last forever and give good light - but it looks like my power is not "good" enough (I live in the top floor of a 61 floor building - not like I can change my power).
Allowing you to buy CFL is great. Forcing me to buy CFL when they don't meet my needs is not.
Get your pitchforks - it's time to march against Congress again...
while (sig==sig) sig=!sig;
Real data, but let me put it in volume terms now.
A container from china costs from 2500$ to 3000$ to ship. They come in 45', 40' and 20' sizes. The smallest fits arount 33 cubic meters. At around 2 CFL per liter you could fit 66000. If we leave extra room let's say 50000. At 3000$ it costs 6 cents to get each CFL to the US. Now even if someone said "2 per liter? Baloney! the most you could fit is 20000!" well, fuel probably only accounts for 60% of the price anyway, so we are still talking cents.
We have less than 10 cents to ship versus 20$ savings. Come on!!! I think people have an aversion to anything china.
http://news.cnet.com/Sourcing-in-China-not-a-sure-bet/2030-1069_3-5561137.html
http://en.wikipedia.org/wiki/Containerization#Dimensions_and_payloads
I just did the posting I am quoting. I am logged on I can see my user (arthernan) at the top of the page. And the "post anonymously" check box is empty.
For accent lighting in my bathroom I installed a half dozen or so 12v recessed lights in the window sill and different colored wine bottles sit on the lights, but due to the heat of the incandescent bulbs I would have one burn out about every week. At $5 to $8 a bulb that gets expensive quick. So I found some marine LED replacement bulbs that cost about $20 to $25 and replaced them all. I haven't had a bulb burn out in 2 years now. Each replacement unit has a cluster of LEDs, perhaps 10 or so, and other than having to shorten the leads to fit inside the curve of the reflector, installation was a snap. The first one I bought for testing purposes had a bluish tint, which I wasn't happy about, but under a blue bottle it doesn't really matter. They come in warm (yellowish) or cool (bluish) since LEDs can't produce a full spectrum you can't get true white. After I was satisfied with the performance I ordered the rest with a yellowish tint. Blueish lighting reminds me too much of the damn florescent lights at work. The LEDs have long since paid for themselves. But I will NOT use CFL in my home. I don't care how much energy they save. If I wanted my home to be lit like an office I'd live at the office. Florescent lighting gives me a headache. If I could imagine a perfect Hell it would be lit with florescent lighting.
Lets make some real numbers in volume terms now.
A container from china costs from 2500$ to 3000$ to ship. They come in 45', 40' and 20' sizes. The smallest fits arount 33 cubic meters. At around 2 CFL per liter you could fit 66000. If we leave extra room let's say 50000. At 3000$ it costs 6 cents to get each CFL to the US. Now even if someone said "2 per liter? Baloney! the most you could fit is 20000!" well, fuel probably only accounts for 60% of the price anyway, so we are still talking cents.
We have less than 10 cents to ship versus 20$ savings. Come on!!! I think people have an aversion to anything china.
http://news.cnet.com/Sourcing-in-China-not-a-sure-bet/2030-1069_3-5561137.html [cnet.com]
http://en.wikipedia.org/wiki/Containerization#Dimensions_and_payloads [wikipedia.org]
What AC->DC transformer? LEDs sink a lot of current when they are over voltage, but they are diodes. Hook them up in series if you must -- half of them in one polarity and half in the opposite and the diode in them automatically rectifies things.
You might add a rectifier (four diodes) and a high frequency oscillator and treat it like a DC-DC problem and charge up an inductor to step down the voltage. But then you have to hook them all up in parallel. Just do it christmas lights fashion and forget the expensive DC-DC converter.
The only problem with LED lights is the high manufacturing cost, so they can't show up on the WalMart shelves for $5. But with a 200k hour lifespan, they are worth more than that. CFL ballasts I agree with you.
We seem to have to replace 6 CFLs for every one incandescent bulb.
Start buying a different brand immediately.
When I first decided to save energy by getting fluorescent lights, I bought a complete special fixture with a special bulb. The brand was "Lights of America" brand. I was totally pleased by the warm, pleasant color of the light, so I bought a bunch more and replaced almost all of the ceiling fixtures in my home.
Then they began to fail.
The light would go out, and I would try to replace the bulb... half the time, the replacement wouldn't work either, the whole light was fried (and the bulb was blackened and ruined when the fixture killed itself). When I was lucky and the replacement bulb worked, it was just a matter of time before it would die again with similar results.
So now I went around my house and replaced the fixtures again, this time with standard fixtures. But I'm putting in compact fluorescent bulbs. There is some brand sold at my local Home Depot that is available with a nice color temperature, and I have yet to have a single one burn out. If it does, it can't possibly require a new fixture, since CFL bulbs are self-contained and incandescent fixtures are tough.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
I would like to switch from incandescents to CFL's or LED's, but one big thing stops me - I like being able to dim my lights to variable levels, depending on a whole host of factors. I know the basics of electricity, like what the difference is between a volt, an amp, an ohm, a watt, etc., and how to evalutate DC circuit diagrams using Kirchoff's laws. I vaguely understand AC, and how it interacts with inductances, capacitors, etc...
So - can someone explain why it's not possible (or at least very difficult) to build a dimmable CFL or LED? I think I understand how dimmers work with incandescent bulbs - they increase the resistance in the circuit, and decrease the voltage drop in the bulb, as well as the current, leading to substantially less power expended, from P = IV.
Just to make sure I've got it right: A 120 W bulb on a 120 volt circuit must have a current of 1 amp through it because P = IV. (I'm ignoring the fact that we are dealing with AC rather than DC, but if I understand correctly, the principle is the same). Therefore, the resistance of the bulb is (from V/I=R) 120 V / 1 A = 120 Ohms. If I put an additional 120 Ohm resistor in series with our bulb, and assuming the voltage from the mains and the resistance of the bulb doesn't change, the overall resistance of the circuit is 120 ohms + 120 ohms = 240 ohms, and therefore the current through the circuit is 120 V / 240 ohms = 0.5 amps. The voltage drops across the bulb and resistor must sum to 120 V, and since they have the same resistance, the voltage drops across each must be equal - therefore they must each be 60 V. Thus the bulb only uses 60 V * 0.5 A = 30 Watts - 1/4 of the previous amount. Of course, the dimmer provides the other 60 V of drop, and the same 0.5 A is going through it as well, so another 30 W is wasted in the dimmer. This 30 W heats up the filament in the bulb much less than 120 W, so the filament glows much more dimly and much more shifted towards the infrared. An incandescent bulb would work whether the circuit was AC or DC.
How does one vary the brightness of a given CFL or LED? And if it's not in a direct fashion, by reducing the voltage available to the CFL/LED by sticking a resistor in the circuit, is there some way through clever electronics to sense the change in voltage, and convert that to a change in whatever it is that varies the brightness of a CFL/LED?
because while the volumes are similar, incandescents weight a small fraction of what CFLs weigh?
In hot areas you get to double up on savings, so to speak. The wasted energy in a light bulb is given off as heat. So if you live in a climate warm enough to need to cool your house, the lightbulbs just add to the problem. You get a 100 watt bulb that is giving of like 90 of that in heat.
CFLs are much better of course. They still give off heat, but far less per amount of light output. So you get a double savings. You cut the amount of energy going in to the light, and cut the amount of heat waste which cuts the amount of cooling you have to do.
All that aside, I love CFLs because they have higher colour temperatures. 6000k lights are nice and blend real well with LCD monitors (which I calibrate to 6500k).
I think people assume too much. An LED is more efficient than a CFL but not a regular fluorescent. A quick calculation comparing the 3 gives me this. Energy Efficiency: LED = 70 Lm/W, CFL = 52 Lm/W, Fluorescent = 83 Lm/W. Cost Efficiency: LED = 5000 H/$, CFL = 1100 H/$, Fluorescent = 8000 H/$. Clearly we shouldn't be using CFL's if we can buy LED replacement bulbs like the one I found on SparkFun but it would be much better to build new houses with fluorescent lights.
Think globally but act within local variable scope.
The directionality of LEDs is a function of the lens in front of the diode itself. The cost is a function of the materials used and rather expensive reflector/base substrate upon which the LED is manufacture. Currently they use a small sapphire base to reflect the LED back-light into the spherical front lens, with the LED at the focal point designed to produce a narrow focused beam forward.
Move the LED to a position that causes the light to be emitted in a broad cone instead of a tight focused beam, and you have your even illumination problem solved. Place the diode chip on a glass substrate (something being perfected at this very moment) and cost of LEDs drops dramatically!
The white produced by LEDs is made by using small Red, Green, and Blue LEDs in close proximity. You could even theoretically give each color channel a separate contact and provide special lighting fixtures the ability to produce mood lighting by shifting the color balance. You might have fixed settings for standard lighting balance types; Incandescent, Flourescent, Flame, Halogen, etc.
LEDs have superior efficiency (little waste heat), superior longevity, superior resistance to mechanical shock (a killer for incandescent lights, they'll soon have superior cost performance, and ultimately have superior lighting flexibility. Why would you use anything else?
EarthLED has a 100-watt equivalent LED bulb that sucks about the same amount of power as the equivalent CFL (13 watts) without the mercury. The reason it's using 13 watts isn't just the high-power LED inside-- it has a small fan inside of it to keep the thing from overheating (yes, the fan could fail, and the chip might fry well short of its stated 50k hour lifespan and long after the warranty expires...). It costs $80, which is good considering that a year or two ago they had a 40-watt equivalent for that price. I might spring for one once the paycheck is in the bank.
If that's still too rich for your wallet, there's a 40-watt equivalent for $40, and a halogen desk-lamp replacement 2-pack for $40. They're not as bright, but they might do the trick for small appliances.
"We are Microsoft. You shall be assimilated. Competition is futile."
Disposing of a CFL releases far less mercury than burning additional coal to power an incandescent bulb does.
The power factor of CFLs is around 50% which means that from an environmental point of view, they take twice the power that it says on the box. Just because it doesn't register on your personal wattmeter doesn't mean it doesn't exist. I think that is important in this discussion. I can see why the promoters of these lights don't want to talk about power factor, but I would have thought that there were some engineers on this forum who wouldn't let it pass so easily.
LEDs are not traditionally used for illumination not only because of the costs of LEDs, but because of the complex optics required to distribute the light. it's rare to see LEDs used for illumination,
I've started using LEDs as replacements for Halogen GU10 bulbs. The ones I have are a 3W single LED type which I tried as replacements for a few 50W Halogen bulbs. Though reasonable, these aren't nearly as bright as the original bulbs but I have seen some 4W versions advertised and may get those when more of the halogens burn out.
I would think that the issue with light distribution could be addressed to some extent with a small circle of "frosted" glass but I have yet to see any that do this (shrug)
It takes about 1000 tons of fuel (call it 200,000 gallons) to ship 2000 40-foot containers (each about 3000 cubic feet) from China to the US. At about 30 bulbs per cubic foot, that would be 180 million bulbs per shipment, or 900 bulbs per gallon. And ships runs on pretty cheap fuel.
By comparison, a truck (with one container) uses about 12 gallons of diesel to go 100 miles (do you have a light bulb factory that close?) - exactly the same 900 bulbs per gallon.
Comment removed based on user account deletion
I've still got lots of old incandescent light bulbs around that aren't used that much, e.g. in wardrobes, cabinets, etc, that are on only for a short time and then off most of the day. They last for ever that way.
When they die eventually, i'll have to replace them with LEDs, because CFL's don't like to be turned on and off so much and they need some time to warm up.
assignment != equality != identity
http://www.olino.org/us/
gives a nice summary of the qualities of available LED, CFL, etc lamps. CRI, Kelvin, Lumen etc.
LEDS became more usable in the last year. The only thing I'm waiting for is a LED lamp that can replace Solux halogens for color critical work, that will take more years. Especially red and blue colors suffer despite some CRI numbers above 85. The CFL's like True-light with improved CRI/Kelvin 5000 are acceptable replacements but do not have the same continuous spectrum the Solux have.
Ernst
...take some sanding paper and make sand your leds lightly - this will make the light much less directional. Yes, you will lose power and thus require more leds.
fair enough but for a _normal_ house there is a considerable saving.
What Is The State Of Solid State LED Lighting?
By Chris Rollins | December 29th 2008 02:12 PM | 12 comments
About Chris Rollins
Chris Rollins is a recent graduate in aerospace engineering from Cal Poly, San Luis Obispo. When he's not snowboarding, he's writing about or researching physics, astronautics, or science policy.... Full Bio
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It seems like they're already everywhere - if you look down at your keyboard, one is providing the little green indicator for your Num Lock key, while another may be frantically blinking to inform you of your waiting voice mail. On your next drive, chances are you will stop at a stoplight lit purely by LED's and perhaps may notice a blinker made up of small, bright lights instead of one bulb. LED's certainly are everywhere, faithfully providing indications of all kinds. But, with a few exceptions, the primary purpose of an LED is to indicate rather than illuminate, despite the fact that LED's do nothing useful besides produce light. A few new developments, however, may bring solid-state lighting into our homes very soon.
Little, but Bright: LED's may be poised to replace incandescent and compact fluorescent bulbs as our home or office light source. Photo Credit: MIT
An LED, or Light Emitting Diode, is a type of circuit element that emits light when electrical current flows through it in the appropriate direction. Like a normal diode, current flow is blocked when it travels against the direction of the diode. When a positive voltage is applied to the positive side of an LED, the electrons that flow are required to jump down in energy as they cross the diode - emitting the lost energy as light. This light is generated at one specific frequency, based on the characteristics of the materials used. When creating white light that may be useful for lighting, however, a blending of many colors is needed - something the LED does not seemed easily poised to accomplish, despite numerous advances in LED technology.
Red light was the first visible light LED to be produced, in 1962, followed by yellow and green. Much later, in the early 1990's, blue-spectrum LED's were developed - a huge advance in usefulness, since blue light can be combined with red and green to make white light. However, this approach was inefficient, and companies were scrambling to make a single diode that could produce white light on its own. Then, in 1993, a company named Nichia created the first white LED using a blue LED with a phosphor coating. The coating was the trick - it provided enough shifting of the light wavelength coming from the diode itself to create white colored light.
Why, then, aren't we using LED's - which are much more efficient than either incandescent or fluorescent bulbs - to light up our homes and offices? The major problem, of course, is cost. Current white LED's require a substrate made of sapphire and an additional mirroring layer to reflect light that would otherwise be lost. As a result, LED lights already on the market cost approximately $100, far too much for the average consumer.
Researchers at Purdue University have found one method of significantly reducing the cost of a white LED by eliminating the expensive layer of sapphire. Instead, they used silicon as the substrate (the material the diode is printed on) and zirconium nitride as the reflector. This had never been done before, mainly because silicon reacts with zirconium nitride and changes its properties. The researchers solved this by putting a layer of aluminum nitride between the silicon and zirconium nitride.
"One of the main achievements in this work was placing a barrier on the silicon substrate to keep the zirc
So this brings up three points.
1.) Why do all the wires in the house need to be connected, let alone connected to the grid? In some applications, why not build in a through-the-wall version of current garden lights? A solar panel (or miniturbine or whatever) on the roof connects to a small battery. The battery connects to, say, a 12v dc area light. This is particularly apt for small standalone structures like a gazebo or even a home office built inside something like a Tuffshed.Of course soffit vents are increasingly done this way already. Maybe lighting is next.
2.) What are the voltages where DC gets dangerous? How far could lines using such current realistically run?
3.) With Katrina followed by Ike followed by... I think that it's safe to say that we'll see more people who actually *like* the idea of a house with a backup second set of wiring hooked up to basic lighting, a phone charger, maybe a couple of fans and a peltier junction cooler. The time might come that they would be very glad to have that backup that just keeps puttering along just fine when the bigger system is down for the count.
Take a look at the spectra of newer LED grow lights. You're right, the older ones were spotty. This is now being addressed just fine. Fwiw, NASA is now planning to use LED arrays as the primary growlights for long-duration missions to Mars.
T8s can be made to 98CRI, which is typically specified for doctors offices. Unfortunately, there is little public pressure to provide higher CRIs in consumer lamps, so the 98CRIs are only in 5000K lights which is great for good lighting and lousy for mimicking the incandescents they replace. The other problem is repeatability of spectrum. If you get an incandescent lamp, it will have practically the same temperature (and CRI=100 of course) as every other lamp in the room. Even if it's not the same wattage or style (save the goofy color correction lamps) the spectrum is blackbody so it blends well. Get two different temperature CFLs in a room (and this goes for LED, too) and you've got a washed out version of disco lighting. That may not be a big deal when you first lamp your fixtures, but as soon as the first one dies it becomes a big issue unless you've stockpiled identical lamps ahead of time.
Is it just my observation, or are there way too many stupid people in the world?
I just did this with an led flashlight and it seems to work fine.
Now, once someone puts more than 45 seconds of thought into the problem, a more elegant solution will surely be found.
I am very small, utmostly microscopic.
But then again, one can always hope that GE and friends will decide to use overpaid American workers with bloated heathcare premuims due to obesity and simply deal with the environmental regulation as a matter of course.... ....or they could simply work Chinese laborers until they drop and pollute China with impunity and get a kickback from the shippers.
I can hear the collective "hmmm" and chin rubbing coming from the board room already.
I am very small, utmostly microscopic.
While I agree with some of your points, please allow me to disagree with your Mertz analogy.
IMO, the suitability of a CFL for a given application is directly tied to the construction and quality of the CFL and its electronics versus the application it is being used in. Some applications will never be good candidates for CFLs, I'll get to that in a bit.
The biggest issue with CFLs as I see it right now is that a lot of junk is being imported with nary a focus on issues that affect consumer utility. Instead, the focus is solely on the lumens/watt, which is but one aspect of how people benefit from a light. For example, most lamp manufacturers do not publish how long it takes their bulbs to come up to temperature, what ambient temperature effects are, nor the color temperature, nor the variability in color temperature, etc.
In other words, other aspects of the light not tied to the lumens being emitted are completely ignored and the cheaper the bulb, the worse the above issues tend to be. For example, I tried buying some CFLs for my in-laws at Home Depot and I was amazed how slow they were to come up to temperature, how nonuniform the light temperatures were, and so on. One bulb would be a dim yellow, the other more orange, etc. and none would have the same luminosity either. In other words, the QC in that factory on that run was completely and utterly off.
Then again, having bought them at Home Depot, I should have known better!
In my own home, I have used CFLs throughout, with a few exceptions. The only areas where CFLs are not used is one hallway that uses a combined light/movement sensor (CFL power supplies hate that due to the method which the light sensor uses) and then there are maybe 5 old sconces with exposed light bulbs where we prefer skinny traditional bulbs. Other than that, everything is CFL, including bathrooms, hallways, outdoor overhead lights, etc. None of these bulbs have needed replacement in over three years of use.
The brands I have had good luck with are TCP and Panasonic. The Panasonic gen IV bulbs we have are perfect replacements for globes, etc. even in antique light fixtures since they have the same approximate shapes as standard light bulbs. They are somewhat slow to warm up to full brightness (maybe 10 seconds - it's our version of a fancy dimmer effect) but we have had great luck using them even in applications that some bulbs are not rated for (i.e. ceiling cans, for example). The TCP springlamps have also been super, offering a wide range of almost instant-on CFLs in many color temperatures with even results. I've not worked for either company, not affiliated, your mileage may vary, etc.
Last but not least, the technology of LEDs will advance just as that for CFL has for the last 20+ years. At some point, manufacturers of CFLs will perhaps get together and come up with a industry standard for electronic dimmer wall switches to talk to CFL ballasts so that CFLs can successfully enter that application also. Unless such interoperability is assured, that is one application where CFLs are unlikely to have a lot of success. Being tied into a single-vendor solution (like the Leviton series of electronic ballast and switch combinations for overhead flourescent lights) is not a solution! And CFLs that can work around ancient rheostat, etc. technology are expensive and not very reliable.
How efficient does it have to be? I realize that incandescents are pretty inefficient, but is there a point where lights are 'efficient enough'? I mean, does it matter that a full-size fluorescent light gets 13 more Lm/W than LED lighting? What about the environmental/disposal aspects of the mercury used in Fluorescents - might it be worth giving up a relatively small efficiency gain, in order to get lights which are less toxic?
Also, there is the matter that people will always want to have the option of having small lamps which don't brightly illuminate an entire room - for those applications, your choices are LED, CFL or incandescent - full size fluorescents, obviously, aren't an option, in which case, it looks like LEDs have advantages over the CFLs (in terms of lifetime, efficiency, and toxicity).
I dunno about typical american practices but here in the UK all lightswitches are rated at least 6A and the standard lighting cable is rated at over 10A in most installation conditions (volt drop permitting of course)
So switching to more efficiant lighting will not significantly affect installation costs. Adding more lighting points on the other hand would probablly significantly increase installation costs (mostly in terms of labour to connect them all up)
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
A glass of cloudy water would do what you ask, quite easily.
Sure, as long as you don't mind destroying the energy efficiency that was the original reason for using LEDs in the first place.
It's definitely not trivial to take a directional light source and shape it so that the output is directionally uniform. I'm a cyclist, and I use LED lights for riding at night. They're just now getting to the point that they're reasonably priced, with decent power, and with a decent beam pattern in maybe a 10-15 degree swath for a single LED. And the ones that use multiple LEDs generally give weird looking beam patterns.
The technology is coming, but it's not fully there yet.
Everyone is assuming that LED's are wonderfully efficient - They aren't.
A cheap LED is only slightly more efficient than a 100w incandescent light.
Only a few very special, very expensive, LEDs can match the efficiency of a fluorescent tube.
And don't forget the cooling problems...
http://discussglobalwarming.com/blog
http://www.telegraph.co.uk/comment/columnists/christopherbooker/3982101/2008-was-the-year-man-made-global-warming-was-disproved.html
I see a lot of people have problems with CFL burning out earlier than expected. But no one wants to look at the quality of the power coming into the house as a possible cause. I know from experience that if there is a lot of noise or leakage from switches on a power circuit then the CFLs will fail prematurely.
I have a friend that says his CFLs flash when they are turned off on occasion. My response to this was to tell him to take them off the X10 (or similar home automation circuit). To my surprise he didn't have them on any automation or dimmer switch, it's just the crappy wiring in the house he's in.
As far as color/temperature quality goes. It's a personal preference. I prefer the warm whites, as the cool white or daylight color temperatures give me a headache. Even the incandescent "daylight" bulbs. I also prefer a brunette over a blond, and Guinness over Budweiser.
Yes, some viewers are indeed more aware. Remember when monitor refresh rates really mattered? A CRT@60HZ really, really bothers me. I can see the refresh(it looks like the screen is blinking), 70HZ usually fixed the problem, but normally found 85hz the easiest on my eyes. Yet, there's plenty of people who handle that 60hz monitor just fine. Otherwise it wouldn't have been a standard.
Given that people have managed to pick up information off of ethernet on the basis of blinking LED status lights on old hubs, LEDs can blink discretely, very, very fast. I can see a simple/cheap circuit that uses a single diode to simply chop off the negative voltage portion, resulting in lights that flicker at 60hz. A couple diodes would give you a 120Hz 'flicker', which most wouldn't be able to see. Add a capaciter to even even that out.
Hmmm... I'm already considering various possibilities...
I don't read AC A human right
I'm not sure which rules the LED league uses, but if it's anything like the NFL, I'll still prefer my Canadian Football League, thank you.
UTF-8: There and Back Again
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I was an early adopter of the CFL bulbs. I, too, noticed that the early generations of these bulbs 1) were slow to ignite 2) took up to a minute to get up to full brightness and 3) Did not last nearly as long as claimed.
It got so bad that I started taking a Sharpie pen and writing the date of purchase on the base of the bulbs so I could take them back for a refund when they did not live up to their guarantee.
However, within the last couple of years they have gotten noticeably better. They ignite faster, are up to full brightness faster, and they last much longer. Since we moved into our house a year ago and installed CFLs, I have not had to replace a single one.
A work that expires before its copyright never enters the public domain and thus enjoys eternal copyright protection.
Wouldn't a diffraction grating produce a bunch of rainbow patterns?
All of which is moot unless you are buying incandescent bulbs that were *not* made in China (or wherever the CFLs were made). It is a silly argument on the face of it, the kind of contrarian knee-jerk that you really should consider before voicing, and certainly before submitting as an article to a public forum.
-Ted
-=-=- Quantum physics - the dreams stuff are made of.
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
How is PG&E getting rich off of this? PG&E only operates in California, so they are certainly not getting rich off the excess energy used in China, or the energy cost of shipping CFL's to the U.S.
Having worked at PG&E in a relevant position, I can assure you that there is a strong correlation between efficient fluorescent adoption, and decrease in the amount of power sold by PG&E (which is exactly what they want for a lot of complicated reasons).
You are comparing a verb with an adjective, but the word "loose" is a verb too, "to set free" as in "loose the dogs of war" or to loosen. Better would be
lose = fail
loose = set free
Free Martian Whores!
Oblig. OnTopic comment: My new 'fridge has LED lighting inside. Makes sense that you wouldn't want a 20-40W heat source _inside_ Mr. Fridge.
You do know that the light turns off when the door is closed?
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
They don't generate heat as such
Yes they do. Powerful LEDs generate quite a bit of heat and require generous heat sinking. Just like everything else, the power that is not used to generate usable light is given off as heat.
AC->DC conversion does
No it doesn't. AC->DC conversion can be done at 90%+ efficiency fairly cheaply if you have a known and constant power requirment.
index of refraction of the casing material presents a problem
Not sure what you mean. It is far, far easier to take a directional point source of light and turn it into a flood than the other way around.
as well that leds don't generate white light by themselves (they use phosphor?)
So do CFLs.
And none of that is really that important. Here is a much better question: How much of the light that we generating is actually doing something useful?
I have recently bought a dozen LED wide angle soft warm "bulbs" that fit into a standard light socket. Even with the wide angle, however, the light is very dim (almost smoky) and is still confined to a small area - I would estimate 90 degrees, with the light growing very diffuse more than a few feet away. Although the brightness is comparable to a 20-watt bulb, it's really an apples/oranges comparison - as a 20 watt incandescent would fill the whole room with dim light instead of a four foot radius with very limited penetration.
I had visions of replacing CFLs in high-use areas with the LED bulbs and just leaving them on around the clock - but one look at the resulting light and my wife was having none of it. "The house looks like a cave full of cigarette smoke," she said.
Just to give you a cfl vs led comparison for these bulbs - if I put LED bulbs in all four outlets of my office ceiling fan/light, the light output is significantly less than a single, 13 watt CFL bulb. I would estimate that the single CFL is 60% brighter than the four LED lamps. The LED's use around 5 watts per bulb, for a total of 20 watts vs the higher light of 13 CFL watts.
Currently, I've found that CFLs are much more efficient than LEDs. I don't believe the lifetime claims of either (has there been an 8 year longitudinal study on which to base those claims?), but the light x watts x cost comparison is much better with CFLs. Many of the arguments against CFLs (noise, flicker, dim start, color) are outdated for most brands. If you buy five-year-old bulbs on ebay, you may run into these problems.
I believe that LEDs will be more efficient than current CFLs in ten years - but who knows how efficient CFLs will be then? And what other technologies, such as OLED wallpaper/posters, will have emerged by then?
I think you missed the getting rid of part, 6 amp switch is rated for 1200 watt situation. If 100 watts now lights your whole house, go look at your electric box, and count the lighting breakers, count the cost for them, and the cost to wire them, and run separate wiring from that to the switches.
Your 6 amp switch needs to pass enough current so if that light is shorted it will pop the breaker without damage, your breakers are rated to protect the wire, and switches.
Now that 1 Amp lights your entire house, and a voltage drop of 20% doesn't affect your lighting intensity at all. Your new entire house lighting wiring can be closer to a phone cable, and your switching can be accomplished by the equivalent of a set of dip switches.
Look under any light, or switch now, you see a 4"x2" box nailed to a 2x4 with thick wires taking every bit of the box up. replace that by phone cable, and a crimp on led, no need for any boxes, no need to plan to replace bulbs, just pull a small flexible 6 conductor cable through the house, where you want a light you drill a 1/16" hole, put a light, crimp on, no need to fix drywall, no need for separate circuits.
I probably would keep the big switches, but instead add a capacitor in the now freed space. Since led lights work equally on ac or dc, a diode, and a capacitor in the switch housing equals a complete lighting ups.
Our University moved to a new campus a few years ago, and the architectural firm tossed in some LED lighting. I thought it would be efficient and trendy, and I wanted to see first-hand how it performed (hey - I'm an engineer :-) ).
:-(
The result: Disappointment
You know those air-deflectors on the back of cars, with an LED-third-taillight, and how many of them seem to have a few dead LED's? Well, that's what our trendy-and-cool LED lighting is like, now.
Each fixture was comprised of about 10 individual white (ish) LED's, and I am estimating that about 50% are not working now, after only 3 years!
Sure, I've done Mil-Std 217 reliability calculations, and I understand that the operating-life *expectancy* for these LED components is high, but it's just not translating into reality. Maybe the manufacturing (of the finished-product) degrades the individual LED's... I don't know.
I just know that the light is harsh, the cost is high, the actual life is low.
My experience with CFL's mirrors that of some other posters: short life, even from the late-90's through 'til now.
So, I am resisting "green-wash", and I buy partly based on TCO (total cost of ownership), which is largely based on purchase-price, and operating-cost, and partly based on light-quality. In most cases, tungsten-filament wins out.
Just my $0.02 at the end of 2008.
Instead of building them in China, build them in EU, Canada, and USA. Overnight, you will see LED's rather quickly.
Can you prove this theory of yours?
If I were God, wouldn't I protect my churches from acts of me?
CFLs use less energy in the home. Shipping is the same as Tradition light bulbs.
What, you don't think they ship tradition light bulbs from China?
Is the poster sop damn afraid of change they half to create some self imposed bubble of ignorance?
The Kruger Dunning explains most post on
So here's a question. The Fine Summary states that CFL's waste lots of fuel just by being shipped here (The US). Are incandescents still made domestically or the submitter just being pissy?
On that page are additional images, one of them shows the product in use. There is a bright blue circle of light below the Nalgene bottle. It pretty much doesn't disperse the light.
The solution used for most good quality LED lamps is to mount multiple LEDs behind the diffusor - Red, green and blue LEDs are more than commonplace, and it allows to mix their outputs by software. Several brands (I'm most familiar with Phillips' Color Kinetics) allow for fully programmable installations. Of course, whole installations are _quite_ expensive, but they do offer even single lightbulbs.
And, yes, a LED lightbulb's lifespan will surely outperform a CFL's. The publicity still says that CFLs will outlast by orders of magnitude incandescent lightbulbs' lifespan, but my experience shows otherwise. Of course, I tend to buy cheap CFLs...
Limited anecdotal evidence suggests that mosquitoes are not attracted to LED flashlights they way they are to full-spectrum light. At least, Siberian mosquitoes weren't in July, 2006.
This is one area where a perceived failing of LEDs (lack of broad spectrum) is actually an asset.
TFP also claims that PG&E is getting rich off CFLs. I'm curious at how the PG&E program that allows me to buy a $2 bulb that would cost $12 out of state is making them rich.
Support SETI@home
This claim is certainly right wing propaganda. Incandescent bulbs don't just magically appear on these shores, and so a direct comparison of CFL vs incandescent is valid. The mercury content of CFLs is a little troubling though and so I greatly anticipate the introduction of widespread LED availability.
Salut,
Jacques
Correct on the advances, but sandbagging on the state of LEDs right now. The "most efficient" LEDs are all blue-ish, but slightly less "efficient" ones (here, efficiency is measured in lumens, which is a biological unit, not a physical one) are not so blue. I use 9 CREE XRE neutral-whites in my kitchen, they look great (and number 10, for the discount, is in my bike helmet spot lamp).
The power LEDs, both CREE and Luxeon, are available in a Lambertian pattern, which is not tightly focused, but can be tightly focused. My helmet has a 6-degree spot on it, it looks great. My bike is set up with two CREEs forward (one spot, one dispersed) and one plain Lambertian Luxeon red-orange to the rear (lights up everything behind me). Imagine, if you will, the delightful treatment these lights get on my bike, riding outdoors, in rain, in snow, etc.
I get all my parts (lights, lenses, current regulators) from ledsupply.com. I bought enough stuff from them this year that they sent me a Christmas card :-).
Self-promotion (and information):
Undercabinet lights: http://dr2chase.wordpress.com/2008/10/19/more-undercabinet-lights/
Bike lights: http://dr2chase.wordpress.com/2008/10/26/converging-on-a-design-for-cheap-bright-bike-lights/
Helmet (showing focus and Lambertian): http://gallery.mac.com/dr2chase/100060/IMG_0679/web.jpg
The information presented is really bad.
1) Waste energy from lamps serves as space heating. Pretty much all houses need space heating for the winter months. Winter is when we need lights the most.
2) I happen to use CFL's in my office. These are on 24x7 because I'm in and out a lot. Three (3)x15 = 45 watts x 24 hours = 1080 watt.hours = 1.080 kWh. At 10 cents this is about $3.00 per month and the waste heat goes into space heating and is therefor not wasted.
I happen to know how long my CFL's last. I got 7 years from the last ones. 7x25x365 = 60,000 hours. The model was a Panasonic EFT 15E28. These have been replaced with 14 watt Philips model 152-744 lamps.
Currently there are about 9,000 hours on the Philips lamps.
Since #1 is in effect for about 7 months of the year here in Calgary where I live, the savings are mostly in the replacement costs of the lamps. At 50,000 hours this is a capital cost of CDN$18 for the CFL lamps from Home Depot. It would be a capital cost of $84.50 for at least 100 bulbs @ 100 watts each.
The electricity costs for the three (3) CFL lamps over 50,000 hours is CDN$210. The electricity costs for the incandescent lamps is CDN$1,008. Total costs are CDN$230 verses CDN$1,092.50 and of course this is for almost 6 years.
It would be nice if they created a standard for that sort of thing -- especially if it were also used for all that electronic stuff that now uses wall warts. I'd love to see houses wired up with 240VAC (for the dryer, fridge, etc.), 120VAC (for other appliances), and 12VDC (for LED lights and small electronics).
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
Most quality bulbs have a higher quality of light than incandescent bulbs. Here is a double blind test: http://www.popularmechanics.com/home_journal/how_to/4215199.html?page=1
All CFLs tested rated higher than the incandescent.
Warm and cool white are things of the past (and have been for about a decade).
Please cite the numbers proving that shipping light bulbs from China costs more than the savings. Oh, and where do you think incandescent light bulbs come from? Oh yeah, China. Idiot.
You must have the worst luck EVER! I've had the same CFLs in my apartment, every single fixture including outside floodlights for over a year without a single failure. The ones outside have survived rain and cold (and are not in an enclosure, because the bulbs are so large at the 30W variety for the amount of lumens a flood requires out there).
Previous to living here, we had CFLs in my house (again, every single fixture, including bathroom vanity and kitchen ballasts) for 4 years. I think we had one burn out, and that was on the back porch where there was some heavy condensation that rusted the fixture itself, grounding it out.
I'm not sure where you're getting your CFLs, but find a new place. I've bought all of ours from Home Depot (before they started carrying the ones that fail to show the brightness value) and WAL*MART. For the odd shape/custom ones, I've always used topbulb.com.