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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."
But it doesn't matter (at least to those of us in the USA), because in 2014 incandescent bulbs will be banned.
End of lesson. You may press the button.
This is the might Slash. We can understand proper units.
Femto = 10^-15
"The price good men pay for indifference to public affairs is to be ruled by evil men." ~Plato (427-347 BC)
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.
This is my sig.
Yeah, and they contain enough mercury to poison 4000 gallons of drinking water! Yay!
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...
Alexander Peter Kristopeit bought his basement from his mommy for one dollar.
... 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.
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.
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.
upon the advice of my lawyer, i have no sig at this time
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.