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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."

4 of 559 comments (clear)

  1. Re:High-efficeiency incandescent bulbs by mrmeval · · Score: 3, Interesting

    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.

    --
    I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
  2. 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.

  3. Production cost by CarpetShark · · Score: 3, Interesting

    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

    ...in 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.

  4. Re:High-efficeiency incandescent bulbs by sumdumass · · Score: 3, Interesting

    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.