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A Super-Efficient Light Bulb

Chroniton writes with news of a Silicon Valley company, Luxim, that has developed a tiny, full-spectrum light bulb, based on a plasma of argon gas, that gives off as much light as a streetlight while using less power. The Tic Tac-sized bulb operates at temperatures up to 6000K and produces 140 lumens/watt, almost ten times as efficient as standard incandescent lamps, and twice the efficiency of high-end LEDs. The new bulbs also have a lifetime of 20,000 hours. There's no mention of mercury or other heavy metals, which pose a problem for compact fluorescents.

17 of 468 comments (clear)

  1. That's all well and good... by Fishchip · · Score: 5, Funny

    but can I use it in a grow-op?

  2. Light pollution by CRCulver · · Score: 5, Insightful

    gives off as much light as a streetlight while using less power.

    Great, people lighting their properties with more bright lights is just what we need. Light pollution is already a serious probably (it's destroyed amateur astronmy, see Mizon's Light Pollution ). Instead of showing people how they can make do with less lights, we're just making it cheaper for private individuals to duplicate the Las Vegas strip.

    1. Re:Light pollution by merreborn · · Score: 5, Insightful

      gives off as much light as a streetlight while using less power.
      Great, people lighting their properties with more bright lights is just what we need
      I missed the part of TFA that said these bulbs were going to be available at prices low enough for home use.

      What makes you think these aren't just going to be used to... replace streetlights? Halving the power usage of streetlights nationwide would reduce atmospheric pollution measurably. If the choice is between light pollution and atmospheric polution... ...light pollution is the more desirable of the two.
    2. Re:Light pollution by pcruce · · Score: 5, Informative

      I agree. The reason it hasn't killed professional ground based astronomy is that it is quite easy to subtract the very focused wavelength of sodium vapor streetlights from an image, as sodium vapor lamps are almost completely monochromatic. If we switched to these full spectrum lamps that would be much more difficult, probably meaning we would only be able to do astronomy in very remote areas or with orbiting observatories. That said, even as strong a proponent of astronomy as I am, the increased efficiency of these lights would probably make it worthwhile...

    3. Re:Light pollution by peragrin · · Score: 5, Informative

      it also affects drivers, and pilots as well. In some regions airports have pushed for local laws to limit light pollution going up into the sky as it interferes with planes landing. Spot lights can temporary blind drivers causing accidents.

      Light pollution isn't so much about astronomy but being able to see when it is dark out, because some idiot is lighting up his yard like fen way park. At night less is more. I can use 5 watt 12 volt bulbs and light up your house better than spotlights. more of the house will be lit with less random dark spaces, and more importantly less shadows in which people can hid.

      --
      i thought once I was found, but it was only a dream.
    4. Re:Light pollution by icebrain · · Score: 5, Informative

      It's times like these that I wish we'd hurry our dumb asses up and build huge observatories on the far side of the moon. Fixed that for you. Of course, the real benefit isn't for light pollution (though that's easy enough to take care of when there's no air), since no "side" of the moon is in perpetual darkness. You have about a 336-hour day.

      The real benefit is for radio astronomy. The far side always faces away from earth, which is a giant radio noise source, and the bulk of the moon itself blocks all the signal. It's really the only place where you won't get such interference (a few space probes notwithstanding).
      --
      The meek may inherit the earth, but the strong shall take the stars.
    5. Re:Light pollution by Original+Replica · · Score: 5, Informative

      If you had ever spent much time in the countryside, you would know how well you can see by moonlight. I've been out during a full moon on a clear night and been able to play soccer with my friends. Driving requires that we can see dozens to hundreds of yards ahead, so need brighter illumination. We can see just fine outside at night for walking speeds. During the vast majority of our evolution we didn't have artificial light, but we did just fine, we still can.

      --
      We are all just people.
  3. Not as low energy as you think by 93+Escort+Wagon · · Score: 5, Informative

    I found it interesting that the tiny bulb - at least in the video - was still using 250 watts and internally generated a temperature of 6000K (no they weren't talking color temp; they were talking actual temp). Now that's certainly lower than the 400 watt conventional streetlight they compared it to; but there's no mention in the video about scalability or low-power use. So the submitter's comment about it having advantages over compact fluorescents may have no basis in fact.

    --
    #DeleteChrome
  4. Re:Commercial use by Cowclops · · Score: 5, Informative

    Heat and temperature are not the same thing. If it produces 140 lumens per watt, I believe that makes it something like 50% efficient (which is insanely high for lighting). That means a 100 watt lightbulb of this technology would turn 50 watts or so into heat, and 50 watts or so into light. A 100 watt incandescant is turning 85 watts into heat and 15 watts into light. So even if it runs at a higher temperature, its confined to a very small space.

    This isn't dangerous at all.

  5. Re:Commercial use by Geoffrey.landis · · Score: 5, Insightful

    Additionally, if it really generated that much heat, it couldn't possibly be as efficient as even the worst incandescents.

    To the contrary. The eye's range of sensitivity is tuned to the solar spectrum, emitted at a blackbody temperature just a bit below 6000 K. A bulb is most efficient if it emits light in the spectrum that the eye is sensitive to, and not in, say the infrared spectrum. So a bulb emitting blackbody spectrum becomes more efficient as the emission temperature goes up, and peaks in efficiency at around 6000.

    Incandescent bulbs are not inefficient because they are too hot-- they are inefficient because they are not hot enough. They run somewhere about 2500 or 3000, and hence most of the light is emitted in the infrared, not the visible.

    --
    http://www.geoffreylandis.com
  6. Re:COLOR temperature, not thermal temp by Anonymous Coward · · Score: 5, Informative

    WTFV (watch the .. video). The temperature they're talking about really is 6000K in heat.

    As other shave pointed out, this is not too much of a problem for household use as ordinary incandescents reach 3600 at the filament. You just need to encase it in a glass bulb.

  7. Re:Somebody please correct my math... by epilido · · Score: 5, Informative

    Lights are not on all of the time. if less than 12 hours use which is likely than your calculations put the life at 5 years in a street light configuration.

  8. Re:COLOR temperature, not thermal temp by poopdeville · · Score: 5, Informative

    In light physics, temperature and color temperature are the same thing. Color temperature refers to the temperature at which an ideal black body radiator will emit such a spectrum. This unit is obviously a temperature.

    Moreover, this lamp appears to be a high bandwidth lamp -- "full spectrum" as they said. This implies that it does not depend on the absorbsion and emission characteristics of specific atoms. Lamps like these -- fluorescents, high efficiency sodium lamps, and the like -- emit light at discrete wavelengths. High bandwidth lamps depend on incandescence to produce light. Indeed, color temperature doesn't make sense for these kinds of lamps -- no black body radiator will emit discrete spectra. (There's a "corrected" color temperature unit for these lamps used in the lighting trade)

    The point is: these lamps get hot. They reach about 6000K.

    --
    After all, I am strangely colored.
  9. they tell you in the video by snsh · · Score: 5, Funny

    Sounds like the company has $40 million in funding. So one bulb costs $40 million.

  10. I did research on these plasma lamps at Cornell by rcb1974 · · Score: 5, Informative
    When I was a student at Cornell, I worked in the Department of Plasma Physics one summer. We got some money from a startup company to do some research on these same types of plasma lamps. I looked at the spectrum of the light these lamps using a spectrometer. Of particular interest to me was the spectrum during the time when the lamp was starting up. I discovered some spectral lines and was able to determine which elements were present inside the bulb (i.e. reverse engineering). I recall there was sulfur, argon, and trace amounts of a other noble gases like krypton. In any case, here are my thoughts on these bulbs.

    The benefits:
    1. Super efficient light (2x as efficient as LEDs)
    2. Gorgeous spectrum. Matches the spectrum of the sun VERY closely. Beautiful white light is emitted and it is extremely intense. I was instructed by my professor to not look directly at the bulb when it was powered on.

    The Drawbacks:
    1. The lamps take about 10 seconds to start up.
    2. After they are powered off, you have to wait about 2 minutes before you can turn them back on again. This is because certain elements inside the bulbs (like sulfur) need to cool down, solidify, and redeposited themselves back onto the interior walls of the quartz bulb.
    3. They must be mounted atop a very large (about 25cm x 25cm x 15cm) magnetron that generates microwaves.
    4. The bulb must be surrounded by a Faraday cage (in this case, a metal screen) so that the microwaves are confined to the area around the bulb only.
    5. The magnetron is bulky, heavy, and noisy
    6. The bulb itself gets VERY hot. They can be a fire hazard.

    They definately have some good applications, like for use in stadiums, airports, etc. However, I think there needs to be more research done to make them usable in homes and automobiles.
  11. Temperature by kf6auf · · Score: 5, Informative

    For any blackbody emitter (incandescent light bulb or this fancy new plasma), the color temperature IS the temperature. It's only for things that don't emit like blackbody radiators (fluorescent and LED) where you have a different color temperature than temperature.

  12. Re:Short answer.... by symbolset · · Score: 5, Interesting

    Time to add nimp.org to your hosts file. The link is an auto redirect from rds.yahoo.com to members.on.nimp.org. This is how Yahoo redirects search results to find out who clicked what. Yawho? search results are thus no longer safe to click. For best results, add rds.yahoo.com to your hosts file or equivalent blocker as well.

    members.on.nimp.org resolves to poulet0.zoy.org. The IP address is [80.65.228.130]. Best to block that as well. The DNS administrator for this server is Slashdot User "Sam H", UID 3979.

    Somebody at slashdot should have a look at our anonymous coward's IP address. It would be nice if we could quit this nonsense. I hope this isn't some troll that bought a low UID in the auction.

    And maybe some slashdotter in Paris could call Sam and ask him to fix his compromised server. It does look like someone truly nasty took it over in August of 2005. Big Debian fan this one. Likes the GNAA routine and the whole bit.

    I'm not certain about pinning this on Sam. sam.zoy.org resolves to a different IP. One of you intertubes wizards want to weigh in here?

    --
    Help stamp out iliturcy.