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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."
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.
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.
Sorry but I don't buy the optics issue. It really can't be THAT hard to put a lens or reflector in the armature and point multiple LEDs in different directions. If anything LEDs should be preferable to incandescents because it is easier to take something very directional and spread the light than it is focus the light from a divergent source. I think the main reason LEDs are not popular yet is cost and "it's not what I'm used to". Seeing the type of crap people will buy even when there are better alternatives I simply don't believe that something as sophisticated as the beam profile of an LED will be a huge issue.
yea it's all marketing. People buy what they hear about. It's the truth and I haven't seen any LED light fixture ads anywhere!
Balderdash!
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!
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The point is not the price but the environment footprint an heavier cargo consume more fuel. I'm not sure this is really signifiant here regarding the weight of cargo and the average weight of other stuff shipped but I may be wrong.
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.
"Better" without specifying or considering criteria is subjective. IMHO a Ferrari is a better car than a Porsche, but by what criteria? I can also say that the Porsche is better than the Ferrari, and not be contradictory because I'm considering different aspects, i.e., am I referring to asthetics, raw performance, comfort, reliability, or cost/hp, or am I even comparing the same model in each statement?
In your case, you're looking at lumens/watt without taking into consideration other factors, such as spread, fixture design, color temperature/purity (existing LED lighting I've seen so far would never work in a design studio or print shop, for example, nor a salon), and so forth. On top of that, some incandescent or even halogen or neon lamps are purely decorative, so LED need not apply in those cases. How would an LED lamp look in a chandelier?
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Have you done it recently? The CFLs I bought in the nineties are still working. The ones I bought last year aren't measurably any longer lasting than the few incandescents I still use. I suspect that now everyone has jumped on the bandwagon, there are a lot of crappy cut-rate CFLs being made. And I'm pretty sure that this isn't being taken into account in figuring overall real-world environmental impact.
Contributing to this, as Fred and Ethyl Mertz buy eight-packs of CFLs at Costco, they're certainly using them in situations where they don't work well -- like areas where the lights go on and off frequently. (I made this mistake initially -- couldn't figure out why CFLs were lasting months rather than years in the bathroom.) Which, as you point out, really is doing it wrong. CFLs work well in narrowly-defined environments -- they're not a replacement for every bulb in the house. The general public doesn't appear to realize this, and the retailers are in no hurry to correct their misunderstanding.
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A glass of cloudy water would do what you ask, quite easily.
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This is partly an interior design problem.
Color and texture.
Paint and paper.
The gas light wasn't oil or candlelight.
The incandescent lamp was harsher and stranger still. The Victorians had to think creatively about how to use these new forms of illumination.
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.
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I guess it's not the LEDs themselves, but you need electronics to down transform and rectify the AC. Now if that's left to the lowest bidder you can expect high failure rates. It's probably the same with the CFLs. Everybody is used to incandescents to fail all the time so it doesn't make a difference if they're crap.
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For something more compact and less wet (a consideration around compact electrical devices): a diffraction grating. Add a glass frosting on top of a couple of layered diffraction gratings to make the light more evenly diffuse.
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so using a 14W (75W equivalent) for reading lamps is probably a minimum.
There is one of the big problems with CFL acceptance. I don't know how they rate the lumens, but the human eye doesn't get a 75w incandescent equivalent amount of light in it from a 14w CFL. You need something more like a 27w CFL to match a 75w incandescent. So, when people buy a CFL that is 14W and claims to be a 75w incandescent equivalent, they feel like the CFLs are too dark. Better labeling would go a long way in improving CFLs reputation. Of course, they wouldn't be able to claim as great of energy savings, but 27w is still way less than 75w.
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.
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Stop buying the el-cheapo crap.
I used to buy the $3.29 CFL's they die, slow warm up, fell like they are on fire.
I switched to buying $8.99-$12.99 Sylvania CFL's and they are instant on even in 21degF temperatures in the garage feel cool to the touch even after running for 4 hours. and they dont change color like the crappy ones do after the first 50 hours.
If you buy the junk, you get junk.
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Agreed. The general public also doesn't seem to be the only ones when you hear about legislators considering legally phasing out incandescent bulb production and sales over the next N years. That may be more feasible if LED lighting can start working in the situations where incandescent lighting stumbles.
Laissez lire, et laissez danser; ces deux amusements ne feront jamais de mal au monde. - Voltaire
Does either company make a 5-pound 4 DCell flashlight built around a sturdy pipe that you would *not* want to be hit with? MagLites double as nightsticks, which is half their appeal. SureFire's "self defense flashlight" looks specifically built for security guards that are forbidden to carry anything useful as a weapon.
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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)
Yeah they looked awful. LEDs produce too much light in the more violet spectrums. Making each of them look like they are surrounded by a purple/black aura to me. The old style lights are a lot warmer and more inviting.
It was a bit off-topic, but it's not viral marketing, I'm an actual customer of theirs.
You are a customer talking about a product you use. That is one of the forms of Viral Marketing.
Back since I was a youngster, we just called it "word of mouth". Worked pretty well for good companies.
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That article repeats a bunch of CFL myths. I find it amazing to watch some in the geek crowd glob onto any "science" related conspiracy ("global warming is fake", "the Hindenburg didn't burn from hydrogen", etc) the same way tin-foil hat people glob onto the "moon hoax" or "there was no plane crash at the Pentagon on 9/11".
We even were treated to one in the header of this article:
"CFLs made in China that are shipped to the US using a lot more fossil fuels than they save."
Oh, really, is that so? Shipping cargo takes about one gallon of gas per ton of cargo per 500 miles. Shanghai is ~6500 miles from LA. Thus, 154 pounds can cross the Pacific per gallon of diesel. A gallon of diesel contains 130MJ. A CFL weighs perhaps a quarter pound. Therefore, it takes 211kJ of fuel energy per bulb. If we assume the big diesel engine is roughly as efficient as a power plant's electricity generation, we can compare them directly. 211 kilojoules is 0.05 kilowatt hours. If usage that bulb reduces 60 watts down to 15, thus saving 45 watts, it'd take barely over an hour to pay off the energy used in shipping it.
Of course, you also need to include train shipping energy consumption to get it to and from the ports, which is more like one gallon per ton per 300 miles, but that too is trivial to pay off.
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You also need to consider that your incandescent bulb still needs to be shipped to you somehow, and it may even come from a Chinese factory close to the CFL factory.
"CFLs made in China that are shipped to the US using a lot more fossil fuels than they save."
Oh, really, is that so? Shipping cargo takes about one gallon of gas per ton of cargo per 500 miles. Shanghai is ~6500 miles from LA. Thus, 154 pounds can cross the Pacific per gallon of diesel. A gallon of diesel contains 130MJ. A CFL weighs perhaps a quarter pound. Therefore, it takes 211kJ of fuel energy per bulb. If we assume the big diesel engine is roughly as efficient as a power plant's electricity generation, we can compare them directly. 211 kilojoules is 0.05 kilowatt hours. If usage that bulb reduces 60 watts down to 15, thus saving 45 watts, it'd take barely over an hour to pay off the energy used in shipping it.
You don't need math to debunk - just Economics 101. If shipping used more energy than it saved, then price of the final product would be too expensive. The fact that they can go for $1/bulb and are often given away for free (not often enough, but I've snagged a half dozen this way) is all the evidence you need to know that this is bullshit. Although it is nice to see the shipping maths (especially onegallon/ton/500miles).
And you also need to consider that the incandescent bulb will burn out faster, so you'll need 10 of them for every 1 CFL.
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.
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.
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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).