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Comments: 559 +- Hardware: Laser Blast Makes Regular Light Bulbs Super-Efficient on Monday June 01 2009, @03:40PM
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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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Now I Understand Lasers (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!
Re:Now I Understand Lasers (Score:5, 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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Re:Now I Understand Lasers (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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Re:Now I Understand Lasers (Score:4, Funny)
I knew a girl like that in high school. At least, that's what other guys said she'd do but she never wanted to go out with me. Still, D&D was fun.
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Re:Now I Understand Lasers (Score:4, Funny)
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.
A person I worked with during the Pioneer 12/13 Venus launch was responsible for a program called "orgeom" (orbital geometry, Fortran 4P on a PDP 11/40 iirc). For a lark, he first computed the trajectory using furlongs per fortnight. Later (I'm sure the two events were not linked) there was a VMS SYSGEN parameter called "IOTA" (an arbitrary value assigning kernel/exec computing time to a process for accounting purposes) somewhere around 4.0 or so that was measured in "microfortnights".
Resolved: Geek humour runs on a 14 day cycle.
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Re:Now I Understand Lasers (Score:5, Funny)
James Bond: Do you expect me to talk?
Auric Goldfinger: No, Mr. Bond, I expect you to be more efficient!
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Re:Now I Understand Lasers (Score:5, Funny)
Couple this thing with a few femtosharks, and my high-efficiency evil lair will be complete.
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Re:Now I Understand Lasers (Score:4, Funny)
Couple this thing with a few femtosharks with frickin' femtolasers, and my high-efficiency evil lair will be complete.
There, fixed that for you.
Parent
And they will hit the shelves in... (Score:5, Funny)
Re:And they will hit the shelves in... (Score:4, Interesting)
You can find CFL bulbs that overcome these limitations [google.com], 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.
Parent
power factor (Score:4, Informative)
a longer description of Power Factor:
http://www.ee.bgu.ac.il/~instlab/Experiments/05_FlurLamp/PowerFactor1.pdf [bgu.ac.il]
Parent
Re:And they will hit the shelves in... (Score:5, 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.
Parent
Re:And they will hit the shelves in... (Score:5, Informative)
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.
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Re:Production cost (Score:5, Informative)
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.
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High-efficeiency incandescent bulbs (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.
Re:High-efficeiency incandescent bulbs (Score:4, Informative)
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Re:High-efficeiency incandescent bulbs (Score:4, Insightful)
Watch for sales of incandescent bulbs to triple in 2013.
Parent
Re:High-efficeiency incandescent bulbs (Score:5, Informative)
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) [slashdot.org] (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.
Parent
Re:High-efficeiency incandescent bulbs (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.
Parent
Re:High-efficeiency incandescent bulbs (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. :)
Parent
Re:High-efficeiency incandescent bulbs (Score:4, Insightful)
Out of genuine curiosity what would you do with the nuclear waste?
Parent
Re:High-efficeiency incandescent bulbs (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.
Parent
Re:High-efficeiency incandescent bulbs (Score:4, Informative)
You don't need to "dispose" of fly ash from coal burning. You give it to concrete makers and they use it as filler in concrete.
But yes, reprocessing is the best use of nuclear waste. It's a lot better than pouring tons of carbon dioxide and various pollutants (including mercury) into the atmosphere.
Parent
Re:High-efficeiency incandescent bulbs (Score:5, 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.
Parent
Re:High-efficeiency incandescent bulbs (Score:4, Insightful)
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.
Okay, pragmatically speaking, how long do you think it will be until enough of our power is produced by nuclear and not by coal for this argument to work? And remember, we're talking pragmatics, so you can't calculate how long from now assuming the entire nation agrees that this is what we should do. Even if we could, we'd be talking decades, but we can't, so it'll be even longer. By the time it happens, I'm betting we'll already be switching to LEDs anyway.
CFLs are a fantastically pragmatic solution for today. They immediately give an efficiency and pollution improvement in most common situations in America. They work in existing outlets. They work today and are only getting better (more efficient, better light, less mercury). If in the future, as in a couple decades from now, we transition to something newer and better, then what's the problem?
Parent
Re:High-efficeiency incandescent bulbs (Score:5, Insightful)
Nuclear works DECADES ago.
Hydroelectric works DECADES ago.
Solar works DECADES ago.
Wind works DECADES ago.
Parent
Re:High-efficeiency incandescent bulbs (Score:4, Informative)
Carnot Efficiency goes up with the temperature [wikipedia.org] you're adding to the system. At the temps nukes run at, it can be quite a bit better than 40%, and a lot better than the best photovoltaic cells in a labratory.
The most efficient use of solar power doesn't come from photovoltaics, but from solar reflectors [wikipedia.org], which are also limited by Carnot Efficiency.
Parent
Re:High-efficeiency incandescent bulbs (Score:5, Insightful)
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.
Parent
Re:High-efficeiency incandescent bulbs (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.
Parent
Re:High-efficeiency incandescent bulbs (Score:4, Insightful)
If the figures in TFA are correct, these slightly more efficient incandescents are about half as efficient as a CFL.
You only need 23W in CFL to make the equivalent of a 100W incandescent bulb. TFA says these new bulbs can do it with 60W. 60W is still 2.6 times as much power as 23W.
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Re:High-efficeiency incandescent bulbs (Score:5, Informative)
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Re:High-efficeiency incandescent bulbs (Score:5, Informative)
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Re:High-efficeiency incandescent bulbs (Score:4, 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.
Parent
Re:High-efficeiency incandescent bulbs (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.
Parent
Too late (Score:4, Insightful)
Re:Too late (Score:5, Funny)
But... with LEDs you don't get to shoot a powerful laser at a tungsten filament!
Parent
Surprising, actually... (Score:5, Insightful)
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...
Consistency (Score:5, 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?
Re:Consistency (Score:5, 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.
Parent
So what about the places that have banned these? (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.
Too late (Score:5, Insightful)
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.
Re:Too late (Score:4, Informative)
Parent
Re:Too late (Score:4, Informative)
Home Depot recycles them for free now and infrastructure to recycle them is spreading all of the time.
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FFS use standard units. (Score:5, Informative)
This is the might Slash. We can understand proper units.
Femto = 10^-15
Lifetime (Score:4, Insightful)
Conservation (of electricity) is a red herring (Score:4, Insightful)
Conservation is a red herring: population growth will outstrip any resulting savings. Instead, we should focus on generating energy sustainably. We can do that today with a combination of wind, hydroelectric, and nuclear power.
Conservation almost always reduces our quality of life. Why should we do that when we have the technology to not only save the environment, but improve our lives as well? We should be encouraging people to use more energy when that power makes life easier. By all rights, electricity should be cheap and plentiful.
I can't help but wonder whether conservation advocates feel guilt over civilization itself. I certainly don't. There's no shame in using technology to make our lives better.
Re:Super Efficient? (Score:5, 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.
Parent
Re:Super Efficient? (Score:5, Informative)
You screwed up your units, there. (watts)x(seconds) = joules [google.com].
You also forgot the negative on the exponent, but I'll forgive you for that...
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Re:This just in... (Score:5, Funny)
There's an app for that.
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Re:This just in... (Score:5, Funny)
The rest goes to feed the sharks.
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