Slashdot Mirror

← Back to Stories (view on slashdot.org)

Lifecycle Energy Costs of LED, CFL Bulbs Calculated

Posted by kdawson on 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.

11 of 400 comments (clear)

  1. LED lighting vs. CFL question by Anonymous Coward · · Score: 2, Interesting

    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:
    MADONNA IS THE BEST!!
    Impeach Obama; install Madonna; end the war!

    Currently listening to: Madonna - Like a Virgin; Justify My Sex remix.flac

    1. Re:LED lighting vs. CFL question by gabebear · · Score: 2, Interesting

      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.

    2. Re:LED lighting vs. CFL question by bestalexguy · · Score: 3, Interesting

      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?

  2. Another things to consider by Sycraft-fu · · 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.

  3. Eh by ShooterNeo · · 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.
     

    1. Re:Eh by ShooterNeo · · Score: 4, 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.

    2. Re:Eh by tftp · · Score: 4, 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.

  4. Re:I haven't had great luck with CFLs by Cimexus · · Score: 3, 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).

  5. Re:Great assumption by Pieroxy · · Score: 2, 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 (in french...)

    --
    Write boring code, not shiny code!
  6. Re:Great assumption by SenseiLeNoir · · Score: 2, 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)

    --
    Have a nice day!
  7. Re:Great assumption by ryanov · · Score: 2, Interesting

    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).