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Comments: 400 +- News: Lifecycle Energy Costs of LED, CFL Bulbs Calculated on Monday November 30, @11:34PM
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kdawson
on Monday November 30, @11:34PM
from the pla-hol dept.
from the pla-hol dept.
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necro81 writes "The NY Times is reporting on a new study from Osram, a German lighting manufacturer, which has calculated the total lifecycle energy costs of three lightbulb technologies and found that both LEDs and CFLs use approximately 20% of the energy of incandescents over their lifetimes. While it is well known that the newer lighting technologies use a fraction of the energy of incandescents to produce the same amount of light, it has not been proven whether higher manufacturing energy costs kept the new lighting from offering a net gain. The study found that the manufacturing and distribution energy costs of all lightbulb technologies are only about 2% of their total lifetime energy cost — a tiny fraction of the energy used to produce light." The study uses the assumption that LEDs last 2.5 times longer than CFLs, and 25 times longer than incandescents.
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Great assumption (Score:5, Funny)
Re: (Score:3, Informative)
Or they never work at all.
Re: (Score:3, Funny)
Assuming LEDs last 2.5 times as long as LEDs, we conclude that LEDs last infinitely long and there is nothing superior except for LEDs.
The study was commissioned by an LED manufacturer. In order to reach the desired result, they had to redefine 2.5 as the multiplicative identity. At least they're up front about it. ("Up front" being, in fact, quite important-- you don't want to see what they did to the associative property.)
Re: (Score:3, Interesting)
To be honest, after having spent more than $400 in LED bulbs (that's not many bulbs trust me), most of them have died after a year or so. I'm talking about the bulbs, not the LEDs of course. I have no doubt they still have 25000 hours in stock, buit without the electronic to light them, it's very little use.
My blog on the subject [palmdrive.net] (in french...)
Re:Great assumption (Score:4, Funny)
ME TOO!
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Re:Great assumption (Score:4, Funny)
That divide by zero could mean undefined and could be infinity. This leads me to the startling conclusion that LEDs don't actually produce light, but actually consume darkness. There is a strange event-horizon inside of LEDs that prevents us from observing what's going on inside. On the inside, I postulate that the mechanism inside of the LEDs let's virtual pairs of "no-tons" and "anti-no-tons" form, orbit, collide, and destroy one another. This releases the occasional photon. There is virtually no heat from this, since no-tons, by nature, are incredibly low energy particles. This must happen at a tremendous rate for the "light output" they give. I am both amazed and slightly afraid of LEDs now that I know how they work. I only hope the manufacturers continue using this awesome ability for good. ...Silly article typos....
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Re:Great assumption (Score:5, Insightful)
Start with outdoor lighting. Outdoor lights, by their very nature, must be sealed. CFLs contain lots of electronic components, including electrolytic capacitors. In a sealed enclosure, these parts can heat up beyond the thermal limits of their components within minutes. Therefore, for outdoor use, you should not use CFLs, period.
Don't be ridiculous. Most street lights aren't incandescents. Most streets are outdoor.
I'm pretty fed up with the same tired B.S. arguments being trotted out by manufacturers to try to convince people to buy CFLs and LED lights.
I think it's clear where the B.S. is.
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Re:Great assumption (Score:5, Informative)
Indeed. Most street lights are sodium vapor (sometimes mercury) vapor: http://en.wikipedia.org/wiki/Sodium_vapor_lamp [wikipedia.org]
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Re: (Score:3, Interesting)
We have used a CFL (not the spiral type, but the stright type, philips) for our outdoor light for the last two years. Its still going strong, and we live in unpredictable London (hot-ish in summer, fscking cold in winter)
Re:Great assumption (Score:4, Informative)
LED lamps will almost certainly have the same thermal failure problems for precisely the same reason. Electronic circuits are simply not designed to operate at such high temperatures, and when you try to use them that way, they will fail much, much sooner than they ordinarily would.
Not to burst your bubble, but you know that LEDs are made from silicon and other semiconductors jut like MOSFETS and CPU's, right? They run at _very_ high temperatures - the max junction temperature of many MOSFETS can run as high as 175-200C!
This figure [ledsmagazine.com] shows a Vfwd vs temp graph of an LED junction temp of 120C.
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Re:Great assumption (Score:5, Informative)
[citation needed]
Sorry, it sounds like you're just resistant to change.
On the subject of outdoor lighting, I started using CFLs in outdoor lights 15 years ago, precisely because the incandescent ones lasted so little time (requiring a ladder to replace, and the associated falling-off-a-ladder risk). At that time, it was the only place I was using CFLs. Even then, they lasted several times longer than incandescent bulbs and used a lot less energy - they had no trouble getting their rated lifetime. At that point we lived in a part of a country that regularly falls well below freezing during the winter. Cold was never a problem. The very same heat you say will break the lamp soon gets the tube warm.
LEDs are expected to become more energy efficient than CFL, so the heat "problem" (which I've never observed) would be even less. LEDs would be absolutely perfect in refrigerators - less heat emitted into the refrigerator which means less work to do for the refrigeration machinery. Since I have built my own LED lighting units from components, I can tell you that (a) they don't have many and (b) no electrolytic capacitors either, and (c) the temperature never gets near exceeding the rated maximum on any of the components at least for 3W Lumiled cool white Luxeon Rebels. The circuit consists of a current regulating power supply (purpose made for LED lighting) - basically a small 5 pin IC, some ceramic chip capacitors, a sense resistor, an inductor, and a schottky diode. Electrolytic capacitors are inappropriate for this small switch mode power supply, their ESR is too high. The power supply circuit for two 3W Rebels is about the size of a postage stamp even on a home-etched PCB. With a factory made PCB you could probably make it half the size without much difficulty.
LEDs are very commonly used for bicycle headlamps, they have almost totally displaced filament lights. I have a 3W LED front light for my bike. It is a sealed, self contained unit complete with battery, about 50% larger than a D-cell battery in each dimension, and will last over an hour off a charge at full brightness. No overheating problems.
The dimming of CFLs as they get old and fail is a much more graceful failure mode than sudden complete failure by an incandescent. It gives you more warning the lamp needs replacing, and doesn't leave you grovelling in the dark trying to replace a bulb when it fails just when it's inconvenient.
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Re:Great assumption (Score:4, Informative)
Oh please. First off, incandescents come in different color spectrums just like CFLs so just because the bulb is incadescent doesn't mean it's "good" light. Second, most of your time spent indoors is under flourescent light (work, restaurants, movie theaters) ergo shopping for work and night-time clothing is best done under flourescents.
You can get CFLs with a Power Factor of 90% or higher, so I call shenanagins. The capacative load increase of a CFL is completely negligible compared to the reduced active power consumption. I point to the fact my power utility is giving away CFLs by the dozen as evidence that power generation/distribution engineers find CFLs to be effective.
I have many CFLs in outdoor applications. I have a barn with 8 bulbs. The first year I put up 6 incandescents and 2 CFLs. My wife was afraid the CFLs wouldn't start up quickly enough so I put up 2 as a test.
In the first year 5 of the 6 incandescents died between our 100F summers and 20F winters. I replaced those 5 with CFLs that have continued to work for the last 2 years. Once my wife decided the CFLs provided good light in winter, I replaced that last incandescent.
Given that 3 of the bulbs are located 25ft off the ground, I really appreciate not having to change the bulbs annually.
I also replaced our two porch spotlights with outdoor CFLs. Yeah, they don't come up to full power immediately in cold weather but I upsized the bulbs. I went from 75W incandescents (950lumens) to 23W (1300 lumen) CFLs so I still have a hefty power savings and they start out almost as bright as the incandescents.
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Re: (Score:3, Insightful)
Are you aware that heat rises? Do you spend a lot of time sitting on your ceiling?
It's all very well to make heat, but it's pointless to be making it where it's not needed. That's not in any way efficient.
Re:Great assumption (Score:4, Informative)
Electric heat? In the US at least, natural gas costs about 1/3 of what electricity does per rendered BTU. Many homes have natural gas heating for this purpose, and deriving heat from electricity could be seen as only contributing 1/3 cost efficiency when considered to be a heat source. Not to mention summer cooling costs; are you suggesting swapping out incandescents for CFLs during the summer months? Interesting theory, I look forward to some math on the subject.
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Coefficient of Performance (Score:4, Informative)
Wikipedia says [wikipedia.org]: "When used for heating a building on a mild day, a typical air-source heat pump has a COP of 3 - 4, whereas a typical electric resistance heater has a COP of 1.0."
So, yes, contrary to popular belief, resistive heating is a terrible waste. Burning the coal in a potbelly stove would be a little better then burning it in a power plant to generate electricity to transmit (with losses) over power lines to heat a wire near your ceiling. But using it to drive a refrigeration cycle would be a far better use of the energy.
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Oh for fucks sake (Score:3, Informative)
How can these "editors" screw up a single sentence? They're not even janitors.
Re: (Score:3, Funny)
I'd say about 10, one to do it the first time and the other 9 for the dupes.
Summary fail (Score:3, Funny)
"LEDs last 2.5 times as long as LEDs"
yeah...
Another things to consider (Score:5, Interesting)
Is heat output. More or less, any energy that isn't becoming light is becoming heat. Now in some areas of the world, that matters little to none. However in hot climates, it does. An incandescent produces more heat which gets dumped in to the air in your house. You then have to run your AC more often. So you end up paying double for the power, in terms of using it and then eliminating the excess. That's one reason I rather like CFLs is that they heat up my place less. I live in the desert so that is a non-trivial thing.
Also, they can have a much more natural white point. I like the fact that you can get CFLs with a white around 6000, which is closer to what you get from the sun on a bright day. Just a much nicer quality of light. You do generally need to pay more to get higher quality ones with a better spectrum, but I'd say it is worth it.
Re:Another things to consider (Score:5, Informative)
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Professional light-bulb changer? (Score:5, Funny)
I am practically a professional light-bulb changer
So, how many of you does it take to... oh, never mind.
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Re:Another things to consider (Score:5, Funny)
I absolutely agree. In winter, instead of turning on your heat, you should just run your computer doing folding@home or whatever to try to put out enough heat to keep your place at a comfy temp. It's crazy to just put the electricity through a resistor when you could be getting CPU cycles out of it!!!
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Re: (Score:3)
Are you claiming that heat output only matters in warm climates? If you've ever been living in one of the northern countries you know that except for two months or so of the year, any extra heat sources in the home is a _good_ thing. Heat production is not wasted energy.
Re:Another things to consider (Score:4, Informative)
I doubt they use incandescent bulbs. High-pressure discharge lamps such as mercury vapor or metal halide bulbs perhaps. These are far more efficient that incandescent bulbs, although not as efficient as LEDs. If they have a yellow color, they will be low-pressure sodium or high-pressure sodium.
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No shit, sherlock. (Score:3, Insightful)
While it is well known that the newer lighting technologies use a fraction of the energy of incandescents to produce the same amount of light, it has been unproven whether higher manufacturing energy costs kept the new lighting from offering a net gain. The study found that the manufacturing and distribution energy costs of all lightbulb technologies are only about 2% of their total lifetime energy cost — a tiny fraction of the energy used to produce light.
A CFL costs maybe $5 each (if you buy a pack with more than one), including the retail markup, and saves maybe $40/year in electricity for supposedly 7+ years. I know manufacturers probably get their energy a bit cheaper than home electric rates, but it can't possibly be the 56+ times cheaper that it would take for the $5 to cover more energy than the $40*7 saved does.
Re:No shit, sherlock. (Score:4, Informative)
I bought n-vision CFLs, which scored the highest in an objective, blind test done by popular mechanics a couple years ago. They were about $2 each with shipping, and have a 9 year warranty. So far, they've lived up to their promise : the light is almost EXACTLY like the light from an incandescent - low color temperature, lots of yellow, etc. They start up instantly, and of course use a fraction of the electricity.
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Re:No shit, sherlock. (Score:5, Funny)
Personally, I'd never trust a lightbulb test done by the blind.
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Re:No shit, sherlock. (Score:5, Informative)
Actually brand-name CFL's delivered to your door [ebay.com] are a little over $1 each.
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Re:No shit, sherlock. (Score:5, Informative)
If you live in the UK don't buy CFLs. Phone your energy supplier and ask them how you can save electric. Mention you like the look of CFLs. They will send you a box for nothing. They will also send you one of these new-fangled LCD energy meters, if you ask. They just sent me enough roof insulation to cover the whole roof space, 270mm thick, for sixteen quid.
They have to do this. It is the law. A certain amount of profit has to be given away for energy saving measures. Everyone qualifies, not just new customers.
Yes, I work in the industry.
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Re:No shit, sherlock. (Score:4, Insightful)
Depends on how you were going to get yourself to the store otherwise.
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Eh (Score:5, Interesting)
Incandescent bulbs :
+ Cheap, we're used to the light
- terrible efficiency, short lifespan, fragile, sensitive to vibration, emit heat
CFLs :
+ much more efficient, very long lifespan
- not very dimmable, contain mercury, fragile, slow to start up in cold environs, reduced lifespan if toggled on and off
LEDs
+ extremely efficient, ridiculous lifespan (60,000 hours), almost bulletproof, can toggle on and off as much as you want, start up instantly in all environs, dimmable, no toxic materials. Basically almost perfect in every way.
- $$$$$$$$$$$$$$$$. Current generation light spectra is too high a color temperature to mimic incandescents. Current generation packaging creates a narrow, focused cone of light.
Summary : LED will pwn all once the problems are solved, and the problems appear solvable. Problems with other light technologies are inherent to the technology itself and not solvable. Once LED is perfected, the other two technologies will be useless.
Re:Eh (Score:5, Interesting)
LEDs [...] no toxic materials
Gallium arsenide is a carcinogen, and arsenic is released when the crystal is exposed to water (after the LED light is thrown out and ends up in a landfill.) Manufacturing of semiconductors is producing poisonous waste, and it requires large amounts of energy.
Currently a 1W desk lamp (of which I happen to have two) uses about 30 LEDs. It is cool to the touch, but the light is mostly blue, and the intensity of the light is just enough to use it as a night light. I like these lamps for what I'm using them, but there is no way currently to replace the overhead lights with them, they are 100x too weak and 10x too expensive.
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Re: (Score:3, Funny)
these days, i wonder whats not a carcinogen...
Re: (Score:3, Funny)
these days, i wonder whats not a carcinogen...
Probably not much besides CO2.
Re:Eh (Score:5, Interesting)
Read what I wrote : problems with current packaging. The reason they do that NOW is that LEDs are so expensive that it's not possible to put enough of them into a light bulb to match the total lumen output of a conventional bulb. So to make use of the limited light output, they leave the light focused in those narrow cones. Once LEDs get cheaper, they'll come packed with diverging lenses or diffusers to spread the light around.
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Re:Eh (Score:4, Insightful)
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Bu.. bu.. but... (Score:5, Insightful)
Re: (Score:3, Funny)
In this case the drawback is that they produce a light spectrum that makes you want to stab yourself in the eye after prolonged exposure.
I know, it's a small nit-pick. I'm probably just trying to justify my foregone decision to not change my "not stabbing myself in the eye" habit.
Easy Bake Ovens (Score:5, Funny)
Doesn't anyone ever think of the children? What about Easy Bake Ovens? Have you ever tried to bake a tiny little cake from the heat emitted by LED bulb? No adult, let alone child, has that sort of patience.
Re: (Score:3, Funny)
I once blew up ten old style 20mA LEDs by mis configuring a bench top power supply. I got some heat out of the arrangement but you wouldn't want to eat the cake afterwards, or for that matter breathe the air.
Pimping LEDs (Score:5, Insightful)
That study as reported in the details didn't show significant difference between overall LED and CFL efficiencies. But the article consistently pushed LEDs. The headline mentioned only LEDs; LEDs were mentioned every time continuing advances were touted, the mercury in CFLs were pointed out (but not the toxic byproducts unique to LED production). The article's picture shows LEDs, not CFLs.
Yet LEDs don't really compete with CFLs yet. The article does mention that even a 60W incandescent equivalent is just experimental in LEDs, though CFLs have brightnesses at all levels even far past equivalence to 100W incandescents. Meanwhile, LEDs still generally aren't as efficient as their equivalent brightness CFLs. And LEDs' extra inefficiency puts heat into rooms that then require extra cooling, which consumes more energy.
LEDs are probably going to outperform CFLs. Their colors will be better than CFLs, their efficiencies probably better than double CFLs. They're smaller, probably able to be less toxic to produce and discard. Their DC power offers better efficiency direct from solar power (or its battery storage) than AC CFLs can get. But not yet. This article makes LEDs seem better than CFLs, but they're not now. It's marketing disguised as reporting. Probably the lack of numbers in an article about engineering performance should be the tipoff.
Re:LED lighting vs. CFL question (Score:5, Insightful)
Because with LEDs you only make the part of the spectrum that the tomatoes growing in the closet use.
Seriously it's the longer life.
Especially the increased on/off cycles, which is what kills almost all CFLs before their time.
Parent
Re:LED lighting vs. CFL question (Score:4, Insightful)
1) You won't need a hazmat team to clean up when one breaks
Can we stop with this already? Unless you start licking the floor where you dropped the bulb, it's not a problem. And if you DO start licking the floor when dropping a bulb, you deserve whatever happens to you (which, in all likelihood, is just going to be a lot of glass shards in your tongue)
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Re: (Score:3, Informative)
Can we stop with dumbasses giving health advice?
http://en.wikipedia.org/wiki/Compact_fluorescent_lamp#Broken_and_discarded_lamps [wikipedia.org]
Re: (Score:3, Insightful)
Re: (Score:3, Interesting)
Re:LED lighting vs. CFL question (Score:4, Insightful)
That has been my experience as well.
I will probably buy $100 worth of incandescents and store them in my attic, once they start rattling their sabres about banning them in my state. I don't MIND CFLs, but they aren't yet up to the quality of incandescents... and their other virtues aren't great enough to make up for the lacking quality of light. I sometimes work on art; CFLs just don't cut it. Anything with severe spectrum peaks fouls up colors.
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Re:I haven't had great luck with CFLs (Score:4, Interesting)
Yeah it seems like CFLs are a great example of YMMV.
I simultaneously replaced all lights in my home with CFLs three years ago. Good quality ones with a nice spectrum similar to old style incandescents (to my eye, at least).
Since then how many have failed? Only one.
I must say I'm quite impressed. Even the outdoor ones haven't died yet (exposed to a typical yearly temperature range of almost 50C). I wouldn't ever go back to incandescents ... and frankly LEDs look even better (less waste heat, potentially better spectrum and range of colours).
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Re:Legislation (Score:4, Insightful)
Incandescents are already 'banned' in many areas of the world (including where I live). That is to say, stores aren't allowed to sell new ones anymore (existing ones that are still going are OK obviously). The exception to this is weird form-factor lights that they don't mass-produce CFLs for (e.g. those little ones you put into bedside tables). But for standard overhead light fittings, incandescents have already gone the way of the dodo here.
Even factoring in the impact of recycling, their total lifecycle environmental impact is considerably less than incandescents. Many vendors that sell CFLs (e.g. hardware stores) also accept back dead ones. And if not, I just pop the dead ones in a box in the back of the car and take them to the dump next time I'm in that area anyway, so the 'extra' travel is minimal. For me at least, it's worth it. My electricity bills are at least $100/year less after moving to CFLs, and they produce less waste heat (which matters to me as I don't have AC!)
LEDs will be better though of course. They should be trashable just like incandescents were, while retaining the energy savings of CFLs.
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Re:Power factor? (Score:4, Informative)
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