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Earth Power News

Lifecycle Energy Costs of LED, CFL Bulbs Calculated 400

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 Anonymous Coward on Tuesday December 01, 2009 @12:40AM (#30279378)

    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?
    Anonymous Coward Sig 2.0:
    Impeach Obama; install Madonna; end the war!

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  • by Sycraft-fu ( 314770 ) on Tuesday December 01, 2009 @12:46AM (#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.

  • Eh (Score:5, Interesting)

    by ShooterNeo ( 555040 ) on Tuesday December 01, 2009 @12:54AM (#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

    + 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:Bu.. bu.. but... (Score:2, Interesting)

    by timmarhy ( 659436 ) on Tuesday December 01, 2009 @01:02AM (#30279526)
    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.

  • Re:Eh (Score:5, Interesting)

    by ShooterNeo ( 555040 ) on Tuesday December 01, 2009 @01:09AM (#30279554)

    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.

  • by Anonymous Coward on Tuesday December 01, 2009 @01:11AM (#30279576)

    I suspect CFLs are less tolerant of a bad power supply than incandescent lightbulbs -- depending on how many power spikes you get they may fail sooner. Also, some makes seem to be better than others. For example, it may just have been bad luck, but all the CFLs I have ever bought from IKEA died fairly quickly. On the other hand, I have several others which have lasted several years.

  • Re:Eh (Score:5, Interesting)

    by tftp ( 111690 ) on Tuesday December 01, 2009 @01:15AM (#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 gabebear ( 251933 ) on Tuesday December 01, 2009 @01:21AM (#30279636) Homepage Journal
    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 [].

    LED technology is still progressing rapidly [], so hopefully we will see LED bulbs that trounce CFL efficiency pretty soon.
  • by Cimexus ( 1355033 ) on Tuesday December 01, 2009 @01:41AM (#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).

  • Re:Eh (Score:1, Interesting)

    by Anonymous Coward on Tuesday December 01, 2009 @01:58AM (#30279862)

    I will beg to differ on the Incandescent bulbs. Specifically, they actually last a very long time at low watts, especially the older "less efficient" ones that used thicker filiments made of different materials. Problem is those older ones put out crap light spectrum... better than candle but not nearly as good as modern incandescent bulbs, which is why they were changed.

    There's such a push to use the newer technologies and incentives to just drop incandescents that nobody seems to be doing any research into ways to make them better. I think that they will go away for most applications but the rush to ban them outright is still a little premature, IMHO.

    There's another issue that is often overlooked- you can make an incandescent bulb of almost any shape and still have plenty of lumes... the LED and CFL technology is still a lot bulkier for the same light output but is slowly getting better. But you just don't have the artistry that the incandescent bulbs offer.

    So on my scale:
    + Simple tech, Cheap, Artistic, No fixture replacements needed, Operating temperature range is fairly wide.
    - Poor efficiency, short lifespan at acceptable light output levels, emit medium heat (Halogens would be high heat), sensitive to Shock (not vibration), reduced lifespan when rapidly switched on/off

    + Long lifespan, high energy efficiency
    - Not nearly as "compact" as the name implies requiring some fixture replacement, Lumes decrease over lifetime, hazardous materials, fragile and sensitive to shock, poor operation in cold, reduced lifespan when switched on/off, subject to strobing/flickering in many environments

    + Very efficient, long lifespan, highly durable, toggle does not reduce life, fast startup, wide operating temp range, no toxic materials, resistent to shock
    - Not well tested, very expensive, wide range of quality in manufacturing, spectrum range issues, non-LED portions of the 'bulb' completely untested, bulky for the lumes.

    Summary: It's hard to compare the Incandescent bulbs to the new technologies in a real fashion. There hasn't been much, if any, new development in this tech area. CFL's are progressing well, but still have issues with being bulky, ugly, and not operating consistently. LED's are almost completely untested, still very expensive, don't have equivalent light output, and introduce new parts of the overall "bulb" that may vary widely between products and which are also highly untested.

    My recommendation: Get CFL's for the bulk of your light fixtures in indoor or temperature-friendly areas, the energy savings is worth it. Keep your incandescent bulbs in custom, specialty, and artistic fixtures, and in temperature zones that cause issues for the CFL's. Hold off on the LED's except on a very limited experimental basis.
    In the next 5 to 10 years we will see a lot of changes in the LED arena, and changes in the CFL but not as many, incandescent bulbs will remain the same & become unavailable due solely to political pressures. By the time your current CFL's wear out and you exhaust your stockpiles of (soon to be "illegal") incandescent bulbs, the arena will have changed enough that you'll want to re-evaluate the choices over-all.

  • Re:Great assumption (Score:3, Interesting)

    by Pieroxy ( 222434 ) on Tuesday December 01, 2009 @05:02AM (#30280720) Homepage

    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 [] (in french...)

  • Re:Great assumption (Score:2, Interesting)

    by jabuzz ( 182671 ) on Tuesday December 01, 2009 @05:36AM (#30280924) Homepage

    The still did not take into account the combination of daylight hours and when central heating systems are on. This is an important consideration for more northerly latitudes. At the moment my incandescent light bulbs are 100% efficient.

  • Re:Great assumption (Score:3, Interesting)

    by SenseiLeNoir ( 699164 ) on Tuesday December 01, 2009 @05:48AM (#30280996)

    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)

  • by bestalexguy ( 959961 ) on Tuesday December 01, 2009 @10:05AM (#30282622)
    What about babies touching the floor and licking their fingers? Do they deserve their fate, too? Which is the right punishment for a toddler whose mother is not an expert in removing poisoning substances from contaminated surfaces? What is unreasonable in trying to keep as many hazardous materials as possible outside the household?
  • Re:Great assumption (Score:3, Interesting)

    by ryanov ( 193048 ) on Tuesday December 01, 2009 @03:36PM (#30287478)
    I have looked at it for CFL's (might have been Philipps, but I'm not sure). The deal there was that the shipping and handling cost of a warranty replacement was more than the bulb. With more expensive LED's, that may not be true, but I was pretty ticked off when I found that out (I had one fail in a few weeks that was clearly defective in some way).

"Even if you're on the right track, you'll get run over if you just sit there." -- Will Rogers