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Power Science

Laser Blast Makes Regular Light Bulbs Super-Efficient 559

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."
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Laser Blast Makes Regular Light Bulbs Super-Efficient

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  • Too bad (Score:1, Interesting)

    by Anonymous Coward on Monday June 01, 2009 @04:55PM (#28173505)

    GE and Philips have already bought and payed for the public perception of which types of lightbulbs are green, and which ones make you a remorseless monster who's worse than hitler.

    Hint: the 'green' one is the one with the enormous profit margin.

  • by Kokuyo ( 549451 ) on Monday June 01, 2009 @04:56PM (#28173513) Journal

    Oh, that's easy to answer. It's a tag. Makes it easy to spot where people have been bought to push certain agendas and fill pockets. Let me just ask you this: Do you think profit margins on old-school bulbs are a) smaller or b) larger than on more modern alternatives?

    Whenever legislation is worded in such a way that it does not encourage competition to reach a certain goal, you can bet your cute fanny that the true goal of said legislation lies not in the stated goal but in the way as to get there.

    That's basically why I'm for voting for politicians AFTER they've been in office. The outcome of said vote will decide how much pension the person gets for the work done. If abysmal enough, I'm all for incarceration.

  • Re:Too late (Score:2, Interesting)

    by BetterSense ( 1398915 ) on Monday June 01, 2009 @06:01PM (#28174539)
    Their light may be fine enough for you perhaps. Maybe you have low standards, or you just don't care about light quality, or maybe you can't tell the difference. I think CFLs' output spectrum is completely unsuitable for anything and won't have them in my house. It's an insult for me to hang paintings and photographs on my wall and light them with a shitty peaky CFL output spectrum. It's completely obviously inferior. Unfortunately, LEDs aren't much better.

    If only there was a lighting technology that could emit a continuous spectrum, maybe even approximating an ideal black body like the sun...

  • by mrmeval ( 662166 ) <<mrmeval> <at> <>> on Monday June 01, 2009 @06:05PM (#28174589) Journal

    I hooked an arduino and solid state relay up to a lamp and stuck a CCFL in it. I set in to cycle it was abou 1S on 1S off 50/50 duty cycle. I walked away to do something and when I came back the bulb had shattered. I now know there are CCFLs meant to be switched on and off for signs but don't know the cost or how much of switching they can take.

    Incandescents won't do that as badly but you should still use DC and a PWM driven circuit to ramp up and down while leaving the filament with some current to keep it warm but not producing light.

  • by Chabo ( 880571 ) on Monday June 01, 2009 @06:18PM (#28174779) Homepage Journal

    First, about LED lighting: what are the environmental costs of producing it? Remember, semiconductors are usually produced in expensive fabs, which are known for needing a lot of fresh water to run. Of course, they do have the advantage of much longer life than other light sources, so this may not be a big problem.

    LED lighting seems to me to be a matter of spending more upfront to gain a long-term benefit, both economically, and -- as you point out -- environmentally. LEDs manufacture causes a certain amount of environmental damage, but they last so much longer than either incandescent or fluorescent bulbs that it seems to be worth it, since we essentially never have to replace the bulbs (with exception for very strange environmental conditions to find in the home).

    I was convinced enough that I replaced the incandescent bulb in my Surefire G2 [] with an LED, to increase my 1-hour battery runtime by a factor of 10. I haven't bothered replacing any of my home lights though, because of the cost.

    Secondly, nuclear power is NOT a panacea.

    I know, and I think that we should diversify our energy sources, but it's much better than coal, and a good stopgap solution until we're able to harness fusion. :)

  • Too late. Bye bye. (Score:3, Interesting)

    by SEWilco ( 27983 ) on Monday June 01, 2009 @06:37PM (#28175019) Journal
    Too late. Incandescent light bulbs are illegal soon. Who needs technology when we have laws?
  • by gabebear ( 251933 ) on Monday June 01, 2009 @06:56PM (#28175213) Homepage Journal
    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.

  • Production cost (Score:3, Interesting)

    by CarpetShark ( 865376 ) on Monday June 01, 2009 @07:01PM (#28175263)

    considering they are as cheap to produce as normal lightbulbs...

    Hold on a sec. They're...

    unleash[ing] as much power as the entire grid of North America onto a spot the size of a needle point order to gain 40W of light output over the course of a lightbulb's lifetime.

    I'm having a little trouble with imagining how it could be efficient to do that for every lightbulb sold.

  • an added bonus (Score:3, Interesting)

    by roc97007 ( 608802 ) on Monday June 01, 2009 @07:14PM (#28175405) Journal

    I remember reading somewhere that incandescent bulbs are made somewhere in America -- Tennessee? Whereas the great majority of CFLs come from China. If incandescent bulbs can be made significantly more efficient, and they're made locally, it sounds like a win-win to me.

  • by RobRyland ( 960596 ) on Monday June 01, 2009 @09:01PM (#28176301)
    A lightbulb works because the filiment gets really hot and glows with blackbody radiation. All of the electric power that goes into the bulb is radiated. So in some sense, the incandecent bulb is already 100% effecient. the only problem is that most of the radiated energy is at infrared frequencies and doesn't do anything to light the room for human eyes. If you increase the emmisivity of the filiment to 100%, it is not obvious that you increase the effeciency of the bulb one iota. In fact, I would guess that the effeciency of the bulb goes down, since the filiment temperature will go down (since you radiate more power at a given temperature) and more of the radiation will be in the IR. Now, if he can change the surface of the filiment so the emmisivity is very high in the visable but very low in the IR, then and only then will he be onto something. -Rob (and yes, I am in fact a physicist)
  • by dbIII ( 701233 ) on Monday June 01, 2009 @10:02PM (#28176719)

    But yes, reprocessing is the best use of nuclear waste

    Nobody has got that to work properly yet. The French made some progress but still have a lot of problems with reprocessing. Having to do absolutely everything by remote control and being very careful about containment makes reprocessing high grade waste a very difficult and expensive task.

  • by sumdumass ( 711423 ) on Tuesday June 02, 2009 @01:06AM (#28177905) Journal

    Of course, other thermal plants (coal, oil, etc.) do the same. I might be overstating the problem, but I do recall an incident a year or two ago where two nuclear plants (out of three along a river) in Tennessee shut down during peak usage in the summer because their river was too hot. And Tennessee is a place where water is rather plentiful, unlike, for instance, Arizona where we have a big nuclear plant a little outside Phoenix.

    The river was too hot because of the lack of water, not the nuclear power. When you dump heat into a river, it is almost instantly and completely transported away from the site. The volume of water mixing with it is also more then the discharge so it won't be a complete 1-1 transference.

    Anyways, a drought in the area caused the river's water levels to drop so low that the sun was heating it up to dangerous temps on it's own. The call to shut the plants down was made because the water levels was too low and the current too slow to carry the heat away. This wasn't a situation where the power plants heated the water too much.

    Plants along the Ohio River had to create contingency plans over the same scenario because throughout the summer the water levels were starting to get low there too.

    Everyone's been connected to the same grid for about 100 years now, and we haven't had problems with neighbors frying each others' electric systems. We already have lots of people with grid-connected generation equipment, and there's no problems. As long as the equipment is certified, I can't imagine any problems. This is a problem easily solved by simply using quality equipment that looks for any problems with the grid-connected power and disconnects in that event.

    This is something that has been a problem in the past. In most states, electric companies have had to employ feedback isolation units to protect pole workers and the line men have special safety procedure they have to employ before servicing an outage, and laws have been passed requiring generators and non-grid power sources to be totally isolated from the mains when in use. Most modern generators have circuit breakers built into them that will trip if the back feed into the grid because of the power drain.

    About 25 years ago, good friend of mine (a line man for AEP) was knocked out of a bucket and fell 16 foot to the ground breaking his leg, arm, collar bone, and ribs plus suffered from burns over 15% of his body from a shock caused by someone plugging a generator into dryer outlet to feed the house without disconnecting the mains. The guy happened to be "fixing" the generator by bypassing the built in circuit breakers because they kept blowing, and achieved the successful fix about the same time he was reconnecting the downed lines. The power interrupters where pulled but the jolt blew a transformer and caused the electricity to jump the safety precautions that were normal at the time.

    The problem and concern is the DIY people who don't spend the money on a qualified electrician to connect the units or don't maintain them properly or modify the systems somehow (putting larger units in place of rated equipment) because of lack of money, knowledge, or whatever reason. It's a real concern when "everybody" has it.

"Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats." -- Howard Aiken