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Laser Blast Makes Regular Light Bulbs Super-Efficient

guruevi writes with news that a process using an ultra-powerful laser can crank up the efficiency of everyday incandescent light bulbs. Using the same laser process covered several years ago, the tungsten filament has an array of nano- and micro-scale structures formed on the surface making the resulting light as bright as a 100-watt bulb while consuming less electricity than a 60-watt bulb and remaining much cheaper to produce. "The key to creating the super-filament is an ultra-brief, ultra-intense beam of light called a femtosecond laser pulse. The laser burst lasts only a few quadrillionths of a second. To get a grasp of that kind of speed, consider that a femtosecond is to a second what a second is to about 32 million years. During its brief burst, Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point. That intense blast forces the surface of the metal to form nanostructures and microstructures that dramatically alter how efficiently light can radiate from the filament."

34 of 559 comments (clear)

  1. Now I Understand Lasers by eldavojohn · · Score: 5, Funny

    Laser Blast Makes Regular Light Bulbs Super-Efficient

    So that whole time in Star Wars, they were just trying to make each other Super-Efficient? That's a whole lot nicer than what I was led to believe was initially going on.

    LASIK makes a lot more sense now too.

    I'm learning!

    --
    My work here is dung.
    1. Re:Now I Understand Lasers by gnick · · Score: 4, Funny

      I think you just redefined "learning". But, it is in line with a lot of the "facts" I've picked up on /.

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    2. Re:Now I Understand Lasers by sesshomaru · · Score: 5, Funny

      James Bond: Do you expect me to talk?

      Auric Goldfinger: No, Mr. Bond, I expect you to be more efficient!

      --
      "MIT betrayed all of its basic principles."
    3. Re:Now I Understand Lasers by bugnuts · · Score: 4, Funny

      Couple this thing with a few femtosharks, and my high-efficiency evil lair will be complete.

    4. Re:Now I Understand Lasers by cheftw · · Score: 5, Funny

      Well I just learned how femtoseconds work. Thanks to TFS.

      Though it might have been more helpfully put if they said that a car travelling at 40 furlongs per fortnight goes 6.652x10^-8 Angstroms in a femtosecond.

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  2. And they will hit the shelves in... by pandymen · · Score: 5, Funny

    So, considering they are as cheap to produce as normal lightbulbs, we can expect to see these on the shelves in...2050?

    1. Re:And they will hit the shelves in... by gabebear · · Score: 4, Interesting
      The mercury is bad, but CFLs have a lot more issues than that
      • Most CFLs are a fire hazard when used with dimmers(even when dimmer is set to maximum)
      • Most CFLs have a power factor of 0.5. A device with a power factor of 0.5 means the device uses twice the rated power. Residential power users don't usually pay for the power needed to correct for a low power factor.

      You can find CFL bulbs that overcome these limitations, but it's unlikely you will find them in a store near you. If you really want to be green, buy florescent lamps where you don't have to throw out the ballast and bulb at the same time and don't use more light than you need.

    2. Re:And they will hit the shelves in... by compro01 · · Score: 4, Informative

      1. Only if you use non-dimmer compatible CFLs. These are findable at the local walmart (at least my local one, YMMV) and are easily identified by "DIMMER COMPATIBLE!!!!" on the packaging.

      2. No, they do not use that power, by definition. The power is sent through the lines and sent back. There is still transmission loss on that power and it increases plant load, but still less than an equivalent incandescent. a 100W equivalent CFL draws 23W, so 46VA (which gives us 40VAR) using his PF=0.5 figure. Let's be generous and say the grid loss is 50%. That brings the real power use to 23+(40*50%)=43W in actual power used and power company having to push out 46VA.

      Compared to a normal 100W incandescent, you're still drawing less than half.

      Compared to this new trick, we're drawing about 3/4s the power.

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    3. Re:And they will hit the shelves in... by sFurbo · · Score: 5, Informative

      Actually, most loads in normal households are inductive, and the CFL are capacitive, so the low power factor increases the overall power factor of a home (some of the unbalanced power from your fridge now only have to travel to the nearest CFL, and not to the local transformer station).

      But don't expect things like facts to convince the people who irrationally hate CFLs, you cannot reason people out of a position they have not reasoned themselves into.

  3. High-efficeiency incandescent bulbs by Verteiron · · Score: 5, Informative

    But it doesn't matter (at least to those of us in the USA), because in 2014 incandescent bulbs will be banned.

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    1. Re:High-efficeiency incandescent bulbs by Grishnakh · · Score: 5, Informative

      Since most power plants in the US (and many other countries too) burn coal, which contains mercury, these slightly-more-efficient incandescent lights will most likely end up dumping more mercury straight into the atmosphere (and then into the waterways with rain) over their lifetime than CFLs, which contain the mercury within the bulbs.

      So in your quest to avoid mercury pollution by using incandescent bulbs, you're actually causing MORE mercury pollution in the long term.

    2. Re:High-efficeiency incandescent bulbs by confused+one · · Score: 4, Informative

      CFL's seem to have a finite number of on-off cycles. Well, that's not completely true... What seems to happen is that if you turn it on for only short periods of time, the life expectancy is reduced. the reduction goes something like 20% loss at 15 min. cycles, 80% loss at 5 min cycles. Counter-intuitive and seems to violate the principle that you should turn off the lamp when you're not in the room.

    3. Re:High-efficeiency incandescent bulbs by DragonWriter · · Score: 5, Informative

      But it doesn't matter (at least to those of us in the USA), because in 2014 incandescent bulbs will be banned.

      This is not correct, and, in fact, the restriction that motivates this misconception is, in fact, the reason why it matters particularly to those of us in the USA. There is no restriction, first of all, of incandescent bulbs meeting one or more of the exclusions or exceptions in Section 321 of the Energy
      Independence and Security Act of 2007 (Pub.L. 110-140) (the law imposing the new restrictions), including:
      * Bulbs producing less than 310 lumens
      * Bulbs producing more than 2600 lumens
      * Bulbs whose operating range is not with 110 V - 130 V
      * Bulbs not intended for "general service" use
      * Bulbs that don't have a "medium screw base"
      * appliance lamps
      * black light lamps
      * bug lamps
      * infrared lamps
      * left-hand thread lamps
      * marine lamps
      * marine signal service lamps
      * mine service lamps
      * plant light lamps
      * reflector lamps
      * rough service lamps
      * shatter-resistant (including shatter-proof and shatter-protected) lamps
      * sign service lamps
      * silver bowl lamps
      * 3-way incadescent lamps
      * traffic signal lamps
      * G shape lamps with a diameter of 5 inches or more
      * T shape lamps using not more than 40 watts or having a length of not more than 10 inches
      * A B, BA, CA, F, G16-1/2, G-25, G30, S, or M-14 lamps using 40 watts or less

      But, more importantly, even for the bulbs those that don't meet one of those exclusions, they aren't banned, they just need to be significantly more efficient than they currently are. Which the improved efficiency claimed by this process (more than meet.

      IOW, if the results claimed are accurate and the process is commercially viable and this efficient for incandescent lamps generally, its quite likely that all classes of incandescent lamps (provided this process was applied to the manufacture of those covered by the Act) could continue to used in the US after the restrictions in the Energy Independence and Security Act of 2007 go into effect, because this would make those bulbs covered by the Act efficient enough to continue to be used under the limits imposed by the Act.

    4. Re:High-efficeiency incandescent bulbs by whiledo · · Score: 5, Informative

      Were these in a bathroom, by chance? Humidity will shorten the life of CFLs. They never say how much, though. I stick with incandescents in the bathroom and outdoors (very cold winters that cause the flourescents to take forever). You may also have some funky electrical problems in your house that the CFLs dying are simply a symptom of. I've bought the cheap home depot ones for years and have replaced maybe one CFL since. That's opposed to the bathroom, where the incandescents have been replaced over and over.

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    5. Re:High-efficeiency incandescent bulbs by Chabo · · Score: 5, Insightful

      Well, the ideal solution so far seems to be widespread LED lighting, combined with widespread nuclear power. With nuclear power, we could use incandescent bulbs without polluting the environment until LED bulbs sufficiently come down in price to be viable for use in every home.

      I consider myself a true environmentalist, like Hank Hill; I believe in finding pragmatic solutions to keep our environmental treasures available for the next generations, by reducing unnecessary waste. Most modern ecomentalists are really just anti-industrialists and anti-technologists, fighting scientific progress. This is why they're opposed to nuclear power -- because it would allow our increasingly technological lifestyle to continue growing without killing the planet.

      Sorry if this seems like a bit of a rant. It's not against you, it's just a beef I have. :)

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    6. Re:High-efficeiency incandescent bulbs by QuoteMstr · · Score: 5, Insightful

      ...most power plants in the US (and many other countries too) burn coal...

      Coal power plants, not light bulbs, are the problem.

      We need a sustainable electric grid, and the best way to create one right now is to tax coal and subsidize alternative power sources.

    7. Re:High-efficeiency incandescent bulbs by ShadowRangerRIT · · Score: 5, Informative

      Assuming you're old enough to have used them, have you ever broken one of the old school mercury thermometers? If so, you've already released the same amount of mercury found in 100 fluorescent bulbs. 95% of the mercury in one of those bulbs can be recycled, so if you do recycle them, it would take 2000 bulbs to equal the mercury in that single broken thermometer. And of course, the additional power consumption means using more power, usually from coal, which is "the largest source of human-caused mercury emissions in the United States," making that incandescent release far more mercury over its lifespan than the fluorescent.

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    8. Re:High-efficeiency incandescent bulbs by whiledo · · Score: 5, Insightful

      Don't let the perfect be the enemy of the good.

      Work on that plan while at the same time working on the CFL plan. Eventually, LEDs will replace CFLs (probably - or something even better). In the meantime, we can offset the tons of waste spewed out by the coal plants which includes mercury along with a whole host of other nasties. Switching to CFLs will actually make it EASIER to eventually replace conventional power plants, as your new technology won't have to support the same peak load.

      So embrace CFLs, knowing that they aren't perfect but they are feasible.

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    9. Re:High-efficeiency incandescent bulbs by iroll · · Score: 5, Insightful

      The same thing that the Japanese and the Europeans do--reprocess it into the smallest possible quantities, and securely bury what's left. The volume of waste that this requires you to bury is inconsequentially small compared to the amount of solid waste (ash) you have to dispose of when you burn coal.

      --
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    10. Re:High-efficeiency incandescent bulbs by sexconker · · Score: 4, Informative

      Uh, nuclear "waste" isn't a problem.

      If it's radioactive we use it smaller plants.
      There are "portable" nuclear reactors designed for neighborhoods, blocks, etc.

      Lower yield material is still useful.
      When it becomes too low-yield to be useful, simply bury it. It won't cause cancer or awaken latent mutant powers in angsty teenagers, even if it got exposed, released, etc.

    11. Re:High-efficeiency incandescent bulbs by sexconker · · Score: 4, Insightful

      Nuclear works DECADES ago.
      Hydroelectric works DECADES ago.
      Solar works DECADES ago.
      Wind works DECADES ago.

  4. Surprising, actually... by fuzzyfuzzyfungus · · Score: 4, Insightful

    The technique has been used to make extremely efficient light-absorbing surfaces; but hadn't been applied to light-emitting surfaces until now. Since those are two sides of the same coin, I'd have expected somebody to try it much sooner(though, I'll admit, I didn't think of it).

    On the plus side, greater efficiency in incandescents is always good(though I'd be quite interested to know how cheap laser treating filaments can possibly be). I predict that this thread will probably be infested by the "CCFLs are Evil!" brigade soon enough...

  5. Consistency by qoncept · · Score: 4, Insightful

    ... and remaining much cheaper to produce.

    ... Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.

    What?

    --
    Whale
    1. Re:Consistency by sjames · · Score: 4, Informative

      ... Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.

      What?

      For one femtosecond (10^-15 seconds). Rough figure from the world factbook shows the U.S. + Canada averaging 497 GW. So, if the laser fired one thousand pulses per second, it would only draw 5 W from the wall (assuming 100% efficiency). It's another case of really big numbers combining with really small numbers to yield nothing spectacular.

  6. So what about the places that have banned these? by Anonymous Coward · · Score: 4, Insightful

    Why not set an efficiency factor on a bulb(like cafe standards) instead of banning the different technologies?

    Something I never understood.

  7. Too late by the_other_chewey · · Score: 4, Insightful

    Too late: Compact fluorescent lamps require about 20W for the same light output as a 100W incadescent.
    And live longer too.

    Yes, their light used to look shitty, but these times are over now as well - if you don't buy the cheapest
    there are, the light out of fluorescent bulbs is perfectly fine. And LED "bulbs" may soon be there too.

  8. FFS use standard units. by B5_geek · · Score: 4, Informative

    This is the might Slash. We can understand proper units.

    Femto = 10^-15

    --
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  9. Re:Super Efficient? by tjstork · · Score: 4, Informative

    Perhaps it operates more efficiently, but it doesn't sound like it is so efficient to produce. Unless I'm misunderstanding or misrepresenting the verbiage from the summary.

    You forgot that femtosecond part. The usage of the whole USA grid is for an incredibly tiny fraction of a second, 10^15 of a second. The USA grid is 4x10^15 watts. So really, if you want to translate it into a more sane energy understanding, its about four watts per bulb to do this.

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  10. Re:Too late by digsbo · · Score: 4, Informative

    Yeah, and they contain enough mercury to poison 4000 gallons of drinking water! Yay!

  11. Re:This just in... by Anonymous Coward · · Score: 5, Funny

    There's an app for that.

  12. Re:Super Efficient? by clone53421 · · Score: 4, Informative

    You screwed up your units, there. (watts)x(seconds) = joules.

    You also forgot the negative on the exponent, but I'll forgive you for that...

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  13. Re:Too late by b4dc0d3r · · Score: 4, Funny

    But... with LEDs you don't get to shoot a powerful laser at a tungsten filament!

  14. Re:This just in... by someone1234 · · Score: 4, Funny

    The rest goes to feed the sharks.

    --
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  15. Re:Production cost by Artraze · · Score: 5, Informative

    You don't seem to appreciate just how short a femtosecond is. As it is only 1e-15sec (1 millionth of a nanosecond), that means a pulse of 1e15W (1 million terawatts) would use only about 1 joule of energy.

    So let's say for the sake of argument that the power and pulse length are both an order of magnitude larger. Then say it's only 10% efficient, so that the process actually takes 1kJ. This energy corresponds to all of 25 seconds at 40W. In other words, the break even lifetime is under one minute.