Posted on 10/07/2007 9:21:00 AM PDT by CutePuppy
[TechView: The Industry]
Reviving Tesla's Wireless Power Initiatives
Kristina Fiore ED Online ID #16478 September 13, 2007
Copyright © 2006 Penton Media, Inc., All rights reserved.
While scientists at the turn of the 20th century were experimenting with the wireless transmission of information, like radio, Croatian-born inventor Nikola Tesla had a grander vision (Fig. 1). He imagined the wireless transmission of power—to supply "light, heat, or motive power anywhere—on sea, or land, or high in the air," he told The New York Times in 1904.
With the help of the October 2006 film The Prestige, where a fictionalized version of the physicist helps an aspiring illusionist develop a magic trick, it's rumored that Tesla was able to light a field of 200 incandescent bulbs from a power source 25 miles away during early experiments at his Colorado Springs laboratory.
No one's sure that happened. Yet Tesla did hold several patents relating to the wireless transmission of energy, part of his wireless "World System," which would send both information and electricity around the globe.
Over time, Tesla's ideas were met with some skepticism as he became reclusive and made bizarre claims like being able to communicate with Mars. Even though the press came to rely on him solely for scientific prophecy, much of Tesla's vision for wireless power transfer is coming into fruition today, through startup companies and research institutions.
WIRELESS POWER The most widespread use of wireless power transfer, albeit on a very small scale, is in passive RFID tags. The tag has no power source, so it relies on the electrical current of an incoming radio frequency signal to power up its CMOS chip and transmit a response.
Bigger wireless-power initiatives debuted at the 2007 Consumer Electronics Show with companies like Powercast and Fulton Innovation's eCoupled technology. A Powercast transmitter can send juice up to 10 feet over RF signals. A receiver that's either built in or attached with an adapter converts the waves into electricity to charge small devices like phones or cameras.
Rather than radio frequency, eCoupled coils transfer energy through inductive coupling, which relies on a shared electromagnetic field (see "Charge Your Gadgets Without Plugging Them In."). Visteon has already used eCoupled induction coils to create wireless cell-phone and MP3 player chargers, which are expected to be released later this year.
While these applications are practical, researchers at the Massachusetts Institute of Technology have come much closer to Tesla's grander vision. At the same time that The Prestige was released last fall, the researchers—led by professor Marin Stoljacic, a great admirer of Tesla's—outlined a way to juice bigger devices without wires. By June, the team lit a 60-W light bulb from a power source seven feet away (Fig. 2).
MIT's "WiTricity" (for "wireless electricity") also relies on magnetic induction to transfer power, but with an added component—resonance. All objects resonate. When two objects resonate at the same frequency, they exchange energy efficiently. It's similar to how a wine glass bursts if it resonates in tune with an opera singer's voice.
The team used two copper coils. The sending coil gave off a non-radiative magnetic field oscillating at megahertz frequencies that resonated in unison with the receiving coil. The coils exchanged energy solely with each other, and any power not picked up by the receiving coil remained bound to the area of the sending coil. Power didn't radiate into the environment, and objects placed between the coils didn't hamper the energy transfer.
The researchers acknowledged that the transfer seems similar to standard magnetic induction used in transformers today, but they also said that such methods can only send power over short distances. Resonant coupling enables magnetic induction to work over greater distances.
And to those who argue Tesla already demonstrated resonant coupling in wireless power transfer, the team wrote in its paper that Tesla's incarnations, like Tesla coils, radiated energy inefficiently in all directions. Stoljacic and his team intend to demonstrate greater efficiency than the 40% that their experiment achieved.
TESLA'S LEGACY For large-scale wireless power transfer like his "World System," Tesla never intended to use coupled resonances. His famous Wardenclyffe Tower, a sprawling 180-foot structure based in Shoreham, Long Island, was to send information and electricity globally via the earth as a giant conductor.
After he sent the first wireless telegraph from Virginia to Hawaii in 1915, Tesla told The New York Times that the "transmission through the earth with the proper apparatus is not more difficult than the sending of a message on a wire strung across a room. This wonderful property of the planet that, electrically speaking, is through its very bigness small, is of incalculable significance for the future of mankind."
But Wardenclyffe never did transmit a telegraph, let alone electricity. As brilliant as Tesla was, he couldn't balance a checkbook. He eventually had to mortgage the Wardenclyffe property to the Waldorf-Astoria Hotel for back rent payments.
The tower was sold for scrap metal in 1917, more than 15 years after its initial construction. Eventually, the accompanying building was purchased by Peerless Photo Products, which was later bought out by AGFA.
Today, AGFA and the New York State Department of Environmental Control (DEC) are conducting a cleanup of photo chemicals dumped on the site over the years. Once cleanup is complete, two non-profit groups—Friends of Science East and the Tesla Wardenclyffe Project—hope to turn the site into the Tesla Museum and Science Center at Wardenclyffe.
They want to raise awareness of Tesla's vital contributions in electrifying society, like setting up the first power generator at Niagara Falls and inventing the concept of alternating current. Outside of engineering circles, The Prestige was the first time many people heard Tesla's name. With recent advances in wireless power transfer, Tesla might finally be recognized as an electricity celebrity.
Printed version of article : http://electronicdesign.com/Articles/Print.cfm?ArticleID=16478
Easily one of the most under-appreciated people in history. I had never even heard of him until just a few years ago. How is it possible that not one of my classes in high school even mentioned him? I heard a lot about Edison, Bell, Marconi, etc, but Tesla was at least as significant.
bump for later
My Inventions: The Autobiography of Nikola Tesla (ISBN 0910077002) is a book compiled and edited by Ben Johnston detailing the work of Nikola Tesla. Nikola Tesla wrote his autobiography My Inventions at the age of 63 in a series of articles for the Electrical experimenter magazine. Much of the content in the book originally appeared in the Electrical experimenter magazine of 1919.
“”The ‘World-System’ has resulted from a combination of several original discoveries made by the inventor in the course of long continued research and experimentation. It makes possible not only the instantaneous and precise wireless transmission of any kind of signals, messages or characters, to all parts of the world, but also the inter-connection of the existing telegraph, telephone, and other signal stations without any change in their present equipment. By its means, for instance, a telephone subscriber here may call up and talk to any other subscriber on the Globe. An inexpensive receiver, not bigger than a watch, will enable him to listen anywhere, on land or sea, to a speech delivered or music played in some other place, however distant. These examples are cited merely to give an idea of the possibilities of this great scientific advance, which annihilates distance and makes that perfect natural conductor, the Earth, available for all the innumerable purposes which human ingenuity has found for a line-wire. One far-reaching result of this is that any device capable of being operated thru one or more wires (at a distance obviously restricted) can likewise be actuated, without artificial conductors and with the same facility and accuracy, at distances to which there are no limits other than those imposed by the physical dimensions of the Globe. Thus, not only will entirely new fields for commercial exploitation be opened up by this ideal method of transmission but the old ones vastly extended. . . .””
there was a great (and very funny) SciFi short story based on this theory. (Great Scifi - 2 volume set) I believe it was called “The Lost Art”
Perhaps the most brilliant kook in history. The hard part was figuring out the line between his brilliance and his kookiness.
Why did Ron Paul's name just pop into my head?
Wouldn’t wireless power transmission be ENORMOUSLY inefficient? Wouldn’t the power available decrease with the square of the distance from the source? And aren’t RFID tags only useful within a super short range of the transmitter?
To me it sounds like Tesla came up with some very interesting ideas, but went a little nuts what with the claims of communicating with Mars, and liked to overstate the potential of his inventions, etc.
jas3
I would think that antennae for frequencies that low would be too big to be very efficient. What's wrong with the centimeter wave range?
Discovery Channel Mythbusters did a show about Tesla’s earthquake machine and showed that even a small device could vibrate large structures when they resonance was spot on.
Tesla is a fricking genius. Bigger than Einstein, IMO.
Because he was world class at screwing up a good thing.
Unlike the businessman Edison, who was no scientist, but a genius of an inspired mechanic, like his friend Henry Ford, and a tireless super-methodical (and supernaturally brilliant) investigator of anything with commercial potential, Tesla was a true scientific genius. Although his discoveries had enormous commercial potential, he was definitely not a business man. On the flip side, Tesla was a genuine uniquely Balkan-type probably paranoid nutcase.
However, if Tesla said he was talking to Mars; take it to the bank, he was talking to Mars. And when the CHICOM get there, they had better learn Serbo-Croatian, or they will never be able to communicate with the natives.
BTW, If you ever want to start a bar fight in Serbia, or Croatia, tell them their dual national hero Tesla was of Croatian, or Serbian, ancestory. There are even rumours of non-Slavic forebears, but you didn't hear it from me, OK?
Because Tesla was an employee of Geo. Westinghouse. Ol'Georgie, a comtemporanious financial baron the likes of Rockefeller, Carnegie and Morgan, did not share the limelight.
Do you remember the name of Carnegie's partner?
How about naming the money man that shoved Edison out of the electrical generation business?
I read some stuff about Tesla many years ago. One of the greatest scientists no one has ever heard of...
I also remember reading somewhere that Edison “stole” some of Tesla’s patents/ideas.
I’ve heard that when he died during the height of the 2nd world war that our government got all of his papers and they haven’t come to public view since........ Urban myth?
But, the original wireless power transmission is sunlight.
I had never even heard of him until just a few years ago. How is it possible that not one of my classes in high school even mentioned him?
~~~~~~~~~~~~~
He was covered in my highschool physics course. I was in the advanced placement class though.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.