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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.
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").
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.
just my wallet. I got a set of LED GU10 bulbs for the flat because when we got in there were two fittings of 4x50W bulbs each, and with the energy saving from some LED replacements (~£10 for 4 at ~2W ea, normally ~£5ea but i found a deal) easily paid the difference, especially since i was having trouble finding CFL replacemetns. However they definately give off significantly less light than the 50W halogens, which is fine most of the time as i prefer a dimmer light usually, but can be a little frustrating if i find myself needing a little extra to look for something, The light is alot 'whiter' which took a couple of days to get used to but is fine now. They are also very directional, they light up one area very well, but are quite poor outside that area, so fine if you are after light in a particular area (they are often advertised as for lighting up some piece of art you want attention drawn to) but not so good if you want to illuminate a room.
an directionality. It's hard to beat CFLs and moreso some good quality fluorescent tubes get slightly more lumens per watt (although I saved 100 watts per hour in the kitchen - 200 instead of 300- by going with directed CFLs that shine line exactly where needed vs previous central flourescent tubes that were lighting from the center trying to sloppily spill light everywhere).
Since every Home Depot now takes any CFLs, the disposal is actually better than fluorescent tubes. Considering most electricity comes from coal, you prevent mercury release in the air vs incandescents. And no, you don't need a specialized clean up crew if a CFL breaks: http://www.snopes.com/medical/toxins/cfl.asp
Except for the oven, fridge, and flashing lights - CFLs are appropriate for most applications.
I would love to have LEDs. But they need to raise their efficiency. They don't generate heat as such, but AC->DC conversion does, index of refraction of the casing material presents a problem, as well that leds don't generate white light by themselves (they use phosphor?) and all that reduces the light given off.
It would be cool if those were solved one day, where they got near 90% theoretical max lumens/wax (683 lm/wt), where a 3 watt LED would give off the same light as a ~100 watt incandescent or ~23 watt CFL. Even 150 or 200 lm/wt would be a revolution. But it will take 5-10 years I suppose.
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
Actually, I have never found a LED bulb nor any CFLs that with a confortable color spectrum.
Also, most inexpensive CFLs lose their brightness very quickly and need to be replaced far sooner than what the manufacturer would have you believe.
No sig for the moment.
I've got a nice, tungesten-coloured LED right here that emits nearly omnidirectional light if I just remove the lens that comes with it. I don't think directionality is really any kind of inherent problem, just a manufacturing issue.
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.
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 really want to switch to LEDs. I've become disillusioned with CFLs in recent years. The very first two CFLs we ever purchased, in the mid-nineties, -- my wife's reading lamp and the hard-to-reach light in the stairwell -- are still working. But in recent years (since maybe 2002) I've had a remarkable number of failures, often in the first month of use, and I rarely see more than a couple years of service. Oddly enough, I get longer service from the outside lights, which should be the harshest environment. The indoor CFL overhead lights (except for that stairwell light) last about a year. The worst service is from the CFL globe lights over the mirrors in the two bathrooms. I lose about one a month, and recently I've started replacing them with incandescents as they burn out.
I think part of this is due to putting CFLs in environments where they do not thrive -- anywhere you have heavy on/off duty cycles like a bathroom or occasionally used overhead. But I wonder also if CFLs in general haven't become (at least in part) victim to "value engineering", IE, making them as cheap as possible.
But anyway, what worries me about LEDs is that although they *should* give longer life, (50K hours vs 15K for CFL and 1K for incandescents) they apparently don't, judging by the LED array stoplights that have been put in all around the city. It's difficult to find one that doesn't have large parts of the array completely out or blinking madly. Around Christmas I noticed that some of them had been replaced with conventional bulbs. Looking at the technology, LEDs should do better, but it's all about implementation.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
I've been using CFL's since at least 1995, probably a lot earlier. Starting with the big Philips 'jam jar' types which lasted more or less forever - I still have some of the first lamps I bought, now more than 15 years old, they still work - and gradually moving to the more recent folded tube and even more recent incandescent form factor ones I have yet to see any trouble with them. They *just work*, save a *lot* of power and hardly ever burn out.
In other words, I completely fail to grasp the reluctance to change over, leading even to conspiracy theories and pseudo-science arguments against these dependable light sources. They may not be the best choice for all applications but they are a good match for most.
--frank[at]unternet.org
That is why they are great in torches, head lamps, and backlights - because you don't need complex optics to focus the light. White LEDs are still quite expensive though, so bulb made out of it would be a lot more expensive than a standard one.
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