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Laser Blast Makes Regular Light Bulbs Super-Efficient

Posted by ScuttleMonkey on from the bright-ideas dept.

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."

7 of 559 comments (clear)

  1. 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 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.

    3. 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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    4. 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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  2. 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.

  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.