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Earth Power News

Lifecycle Energy Costs of LED, CFL Bulbs Calculated 400

Posted by kdawson
from the pla-hol dept.
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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Lifecycle Energy Costs of LED, CFL Bulbs Calculated

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  • by CrazyJim1 (809850) * on Monday November 30, 2009 @11:36PM (#30279340) Journal
    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.
    • Aleph-one etc etc

    • Re: (Score:3, Informative)

      by Rising Ape (1620461)

      Or they never work at all.

    • Re: (Score:3, Funny)

      by startled (144833)

      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.)

    • Brilliant!
    • by Odinlake (1057938)
      On a serious note though, I wonder how that "25 times" assumption stands if you include the effect of children playing indoor football etc.
    • Re: (Score:3, Interesting)

      by Pieroxy (222434)

      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...)

  • by Anonymous Coward

    Does anyone know if LED lighting can save on power over CFL with the same output (lumens)?

    I purchased some LED bulbs and they tend to be much more expensive and the savings (watt rating) is very negligible. What makes LED more attractive? Is it just the longer life time?
    --
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    • by HornWumpus (783565) on Tuesday December 01, 2009 @12:01AM (#30279518)

      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.

    • Re: (Score:2, Interesting)

      by gabebear (251933)
      Probably the single best thing about the current LED bulbs is you can throw them away. All florescent bulbs(CFLs included) contain mercury. Also, CFLs that operate in freezing conditions are very expensive and still don't work that well. LEDs can also be dimmed easily and come in any color you want, or even every color [vitaminshoppe.com].

      LED technology is still progressing rapidly [wikipedia.org], so hopefully we will see LED bulbs that trounce CFL efficiency pretty soon.
  • Oh for fucks sake (Score:3, Informative)

    by ArchieBunker (132337) on Monday November 30, 2009 @11:42PM (#30279396) Homepage

    How can these "editors" screw up a single sentence? They're not even janitors.

  • by jaxtherat (1165473) on Monday November 30, 2009 @11:43PM (#30279402) Homepage

    "LEDs last 2.5 times as long as LEDs"

    yeah...

  • I know, I know, buzzword alert.

    Whats the TCO?

    $X for bulb
    $Y per kwh (cite sources, current prices in what locale, projected prices)
    Z lifetime
    Q consumption rate

    Google shows a few results from manufacturers press releases.

  • by Sycraft-fu (314770) on Monday November 30, 2009 @11:46PM (#30279426)

    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.

    • by hedgemage (934558) on Monday November 30, 2009 @11:55PM (#30279478)
      I am practically a professional light-bulb changer, so I will say that in my non-scientific, non-measured, purely anecdotal experience, that CFLs put out a lot more heat than LEDs. Scads less than incandescents, but still, the ballast in the base of a CFL warms up quite a bit during operation, often growing too hot to touch when the glass spiral is still plenty cool. If you're concerned about minimizing heat, go LED.
      • by jhol13 (1087781)

        The efficiency of CFLs and LEDs is pretty much same, therefore they will put very closely same amount of heat.
        CFLs may heat the base more (no experience), but overall there cannot be any difference.

      • Currently, all the LEDs I've found are too pricey. I have found some cheap ones, but I wasn't satisfied with the light output, or the light quality. I've found ones I liked quite a lot (Color Kinetics makes some fantastic units) but they are too expensive and often not designed for socket replacement.

        I think in a few more years it'll probalby be something for me to do, but not just yet. I have to be pleased with the light output and quality, and I'm really not going to pay more than $100 per bulb, and reall

      • by SteveFoerster (136027) <steve@ s t evefoerster.com> on Tuesday December 01, 2009 @12:48AM (#30279808) Homepage

        I am practically a professional light-bulb changer

        So, how many of you does it take to... oh, never mind.

      • by rtb61 (674572)

        So if you live in a cold climate, where heat and light are required simultaneously, then technically speaking the extra energy put into manufacturing more complex LEDs and CFLs makes them more energy inefficient than long life incandescent light fixtures as you are making use of the heat. Always a tricky question in warm climates, which is more energy efficient trying to cool the additional heat load of natural lighting ie. big windows, or making use of energy efficient LED's and sticking to highly insulat

    • by Z80xxc! (1111479)
      The heat issue goes both ways, too. Portland, OR recently started using LEDs in all of the street lamps, slowly fazing them in as the old incandescent bulbs fail and need to be replaced. Last winter during a huge snow and ice storm, they noticed that a lot of the LED street lamps couldn't be seen. The old warm incandescent bulbs would get so hot that they would melt all of the snow and ice off of the lamp cover. The new LEDs are so efficient that the snow doesn't melt, causing them to not be as visible when
      • by whoever57 (658626) on Tuesday December 01, 2009 @01:34AM (#30280014) Journal

        The heat issue goes both ways, too. Portland, OR recently started using LEDs in all of the street lamps, slowly fazing them in as the old incandescent bulbs fail and need to be replaced

        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.

    • by xlsior (524145)
      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.

      Don't forget the other way around: if you have electrical heating, there are little to no savings using compac
    • Wait... What?

      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.
  • No shit, sherlock. (Score:3, Insightful)

    by Timothy Brownawell (627747) <tbrownaw@prjek.net> on Monday November 30, 2009 @11:51PM (#30279448) Homepage Journal

    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.

  • Eh (Score:5, Interesting)

    by ShooterNeo (555040) on Monday November 30, 2009 @11:54PM (#30279468)

    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)

      by tftp (111690) on Tuesday December 01, 2009 @12:15AM (#30279596) Homepage

      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.

    • by blueg3 (192743)

      Many LEDs are made out of toxic materials (like gallium aresenide). Neither they nor CFLs (which contain something like 4 mg of elemental mercury) present a significant hazard to the user.

    • You can now buy an LED light bulb for 10 bucks from Home depot. Seems like your major complaint about LED's had been solved... LEDs now pay for themselves when compared to a CFL within 1 year, and when compared to incandescent within 3 months.
    • by syousef (465911)

      LEDs - $$$$$$$$$$$$$$$$.

      http://www.dealextreme.com/details.dx/sku.13442

      http://www.dealextreme.com/details.dx/sku.24201

      Price isn't such a limitation any more. Once we see true mass production it'll be sweet.

      Incandescents have awful colour temp anyway.

    • Halogens:
      + Cheap, we're used to the warm light, longish lifespan, resistant to power fluctuations, instant on, dimmable, non polluting, non toxic, can be used in recessed and enclosed fixtures.
      - Bad efficiency (as opposed to terrible)

      Halogens already solve all the main lighting problems except efficiency. But if you're in a cold climate the waste heat offsets the heating bill, raising their effective efficiency. I've never seen this factored into any analysis, but for instance if you compare a 20w CFL to

  • Bu.. bu.. but... (Score:5, Insightful)

    by timeOday (582209) on Monday November 30, 2009 @11:54PM (#30279470)
    Since this is an energy-saving technology, surely it has some fatal yet under-appreciated drawback that fully justifies my foregone decision never to change my habits or lifestyle for any reason and makes fools of the "greenies" in my own mind! You know, like how Hummers are actually more eco-friendly than the Prius [thetorquereport.com], and how windmills screw with feng shui [wind-watch.org]. I've always found an excuse to view all environmentalism as self-defeating before, don't let me down this time slashdot!
    • Re: (Score:2, Interesting)

      by timmarhy (659436)
      if by greenies you mean greenpeace, they make fools of themselfs easily.

      i think while this report is bullcrap on how much of a saving you get from led's, in general it's right - there really isn't a reason to keep using incandescent bulbs anymore. I plan on building a new house next year and it'll be all led driven from a dedicated 12v circuit in my house that will run outdoor lighting as well as my bar fridge.

      • by Cimexus (1355033)

        I'm pretty sure 'greenies' refers to a much broader spectrum of people than the (admittedly nutty) people at Greenpeace...

    • Re: (Score:3, Funny)

      by glwtta (532858)
      Since this is an energy-saving technology, surely it has some fatal yet under-appreciated drawback that fully justifies my foregone decision never to change my habits or lifestyle for any reason

      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.
    • I have tried CFLs many times (in the two condos I have lived in for the last few years), and they have never lasted as long as incandescent bulbs. Our house isn't that strange, so I have to assume that CFLs have some pretty serious problems. Since every time one of these articles gets posted on Slashdot we see many people voicing the same concerns, I think there are some pretty serious issues. I'm not sure why they are continuously ignored - if those issues are solved, CFLs would likely see broader adopti
    • Re: (Score:2, Funny)

      Let me try to help...

      Packaging large amounts of vacuum in incandescent lamps and CRTs increases the concentration of air we've got to breath if we're not living in a lamp or CRT.

      Switching to these so-called green technologies could see us run out of air!!!

  • by Dan East (318230) on Monday November 30, 2009 @11:55PM (#30279480) Homepage Journal

    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)

      by MichaelSmith (789609)

      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.

    • Easy Bake Ovens don't use lightbulbs anymore, they have a small electric heating element built in.
  • by MrMista_B (891430)

    "The study uses the assumption that LEDs last 2.5 times longer than CFLs, and 25 times longer than incandescents."

    So...

    They made it all up.

    They /guessed/.

    They didn't do any research, and didn't actually study anything, they just invented some numbers, then played with them.

    No wonder so many people think so poorly of the environmental movement, if garbage like this gets any sort of positive press at all.

    • I agree the numbers have been pulled out of their asses. However if you would bother to actually look at the numbers for commercially. The gains for LED's are actually a lot more beneficial than the study says. The stated life expectancy for newer LED's are around 100,000 hours. Around 10 X that of CFL's. not 2.5X. You pointlessly blaming this on the "environmental movement" Its just stupid. If anything the environmental movement would overstate the benefits of LEDs ..... not underestimate......:"dumbass"..
    • by blueg3 (192743)

      How exactly is a report by a semiconductor company, clearly for the purposes of promoting LED lights, the product of "the environmental movement"?

      On another note, it's interesting that you manage to turn a single assumption (albeit a significant one) and turn that into "they didn't do any research". This might well be the case if all the information they came back with was the consequences of a the different lifetimes, but that's not the case. The primary product of the study -- which the summary, even, is

  • At my old house they burned out a lot on me. Back then they were $5 a pop and it was rather irritating replacing the same bulb 3 times in a row during a several month period.
    • by westyvw (653833)

      I have not been very happy with them either. They do seem to burn out *years* before they should, often in the same timeframe or less then incandescent.
      Worse, in small spaces, like a bathroom, two or more tend to get hot and off-gas (polyvinyl chloride base is my guess), and then when they do burn out they often get hotter still and turn brown or buzz.
      Do I think the sky is falling? No, but this is not something I have great confidence in for a closed up for the winter household.

      • I think I toggle them too often. My CFLs have always burnt out in a year or so, even in two very different houses in different parts of the country.

        I've stopped buying them. I've got maybe two or three fixtures in the whole house where they'd make sense, and even those I want to be able to turn on for just a second or two a few times a day without worrying that I'm gonna kill the stupid CFLs.

    • by Cimexus (1355033) on Tuesday December 01, 2009 @12:41AM (#30279770)

      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).

    • the ballast used in the cfl's seem to have a limited on-off cycle life; or, the life expectancy is inversely proportional to the on time. If the typical on time is on the order of 5 minutes, you'll see less than 20% of the rated life expectancy. To achieve the full life expectancy the on time has to be greater than 2 hours. Don't use them in bathrooms and similar locations where they'll be switched on and off a lot -- use standard incandescent or better yet halogen bulbs in those applications.
  • ....the fact that you can't freaking READ by the damn lights. CFL == Crappy Fscking Light. I wish it weren't true, but I've tried dozens of brands, and even the ones that make me most happy are only good for general purpose hallway lights and such. I hate putting them in anywhere I have to read. For as bright as they seem to be, they are so narrow in spectrum as to be sort of lacking in their ability to illuminate.

    So far, no experience with LED's on this subject.

    • by drinkypoo (153816)

      I use a 4W LED spot as a reading light. I got it for about three bucks from geeks.com, and it is okay. It seems less flickery than CFL. It's not very bright, but it is pretty well-focused for a page. I can't tell you how you'd like it, though.

  • Hope for http://www.vu1.com/technology/technology.htm [vu1.com]
    No mercury, highly energy efficient, light quality identical to incandescent, not to expensive.
    Why suffer if you break a light for some eco cult?
    Wait for better tech and stay away from the lights of brain death.
  • Pimping LEDs (Score:5, Insightful)

    by Doc Ruby (173196) on Tuesday December 01, 2009 @01:28AM (#30279978) Homepage Journal

    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.

  • Power factor? (Score:2, Insightful)

    I wonder if this analysis took into account CFL's poor power factor. Cheap CFLs usually have a power factor of around 0.5, which causes substantial electrical losses compared to Incandescent bulbs, which are purely resistive (and therefore have a power factor of 1.0). LEDs, on the other hand, have a pretty good power factor. http://www.theengineer.co.uk/opinion/led-is-the-answer/299821.article [theengineer.co.uk]

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