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MIT Wirelessly Powers a Lightbulb
kcurtis writes "According to the Boston Globe, MIT Researchers have powered a light bulb remotely. The successful experiment lit a 60-watt light bulb from a power source two meters away, with no physical connection between the power source and the light bulb. Details about WiTricity, or wireless electricity, are scheduled to be reported today in Science Express, the advance online publication of the journal Science, the Massachusetts Institute of Technology said. 'The team from MIT is not the first group to suggest wireless energy transfer. Nineteenth-century physicist and engineer Nikola Tesla experimented with long-range wireless energy transfer, but his most ambitious attempt - the 29m high aerial known as Wardenclyffe Tower, in New York - failed when he ran out of money. Others have worked on highly directional mechanisms of energy transfer such as lasers. However, unlike the MIT work, these require an uninterrupted line of sight, and are therefore not good for powering objects around the home.'"
Hell, back in the 60s, I had a monstrous WWII surplus transmitter, a BC-610 by name. This thing was the size of a large washing machine, and had vacuum tubes in it the size of your head. It would produce a vertiable torrent of RF. As a young ham operator, I was a little sketchy on the principles and practice of proper antenna load and impedance matching, so the whole feedline was radiating, and causing standing waves in all of the house wiring...in my house and the houses around ours. Enough power was intercepted by house wiring that the incandescent bulbs in light fixtures would glow dimly when I was on the air...even though they were turned off. You could hear my voice on telephones for approximately 10 houses radius, since non-linearities in the old phones were enough of a rectifier to do AM detection on the signal the phoen wiring picked up. Fluorescent tubes in my house & my immediate neighbours would light with a strange plasma looking pattern, caused by the structure of the standing waves present. And forget watching TV or listening to the radio in the neighborhood - my voice was heard on radios louder than the program material, and TV pictures were obliterated by a dancing pattern of hum bars. Enough complaining got back to my parents that I could only operate late late late at night....anyway, you can see why I am not that impressed with the concept of wireless power transmission...I did it in person over 40 years ago...
There is no God, and Dirac is his prophet.
I came across this technology completely serendipitously a few weeks ago on How Things Work. There was a link to "wireless electricity" off the main page and I followed it and they discussed the MIT patents and I downloaded several different patents in the field. They were all from within the last few years and involved resonance coupled with induction.
What surprised me was the lack of imagination in the applications. They were talking about remotely recharging cell phones and MP3 players or letting you move around electronics without needing to find a plug. Well those are all fine ideas and quite obvious indeed but I saw nothing about the one area that seemed to potentially benefit the most from this: robotics.
All the pieces are there in robotics except for the one that this technology addresses: lightweight, high-density power. Oh, and let's not forget cheap.
Powering the lights without wires is a fine thing to do. I'm all for it. But what is the high energy deensity application that absolutely requires mobility? It seems to me that there is one in particular and that is robotics.
Moreover, this technology has a limitation of range that actually becomes a feature when applied to robotics. As we know all too well in the age of Iragi battle drones Asimov's laws of robotics are a fantasy relic of a time that couldn't imagine how software would really develop. The truth is, robots can be dangerous and this kind of technology effectively puts a leash on their range. They can do whatever within the home, but they can't just go out and go for a walk. It's a classic example of a limitation becoming a feauture.
So how would it solve the immigration issue?
I just mentioned this range limitation. So then, how could we use this for agricultural robots that would alleviate the need for low paid illegal immigrant farm labor? No problem. Obviously tractors bring their own power sources into the field. So, power in the field is not a problem. You would simply have gangs of robots attatched to resonant inductor power modules hanging off arms of the tractor. Say each tractor controls six platoons of robotic field hands with six resonant inductor orbs. They could work twenty four hours shifts. One tractor and labor gang could harvest dozens of farms per season in a timely manner.
If you need higher power, that's not a problem. There's no reason this technology is limited to 110volts. You can use 600V or 1200V. As much as you need. Your robotic workers would be as powerful as necessary.
Not only would it eliminate the need for foreign labor, it would also reduce the need to use high impact farming techniques such as posioning the soil with bromide gas and laying down plastic mulch. These things are done in the name of economy because it's too expensive to have human labor go through a farm and pick weeds. Monocrops are also planted for the same economic considerations. By dramatically shifting the labor equation you would enable a vast increase in the use of organic farming techniques.
The implications of this technology are far more revolutionary than re-charging an MP3 player.
While 40% isn't great for general use, I'd wager that it's several times more efficient, system-wide, than using non-rechargable batteries.
I wonder how well it takes to moving objects. Such a system could be a boon for moving us toward grid-powered electric vehicles if there were regular transmission coils embedded in heavily-trafficked roads, and they'd be a lot closer to the car than 7 feet, so they'd probably get much higher effiency numbers (perhaps even comparable to battery charge/discharge losses).
Nothing says 'welcome to the neighborhood' like a gunny sack full of dead squirrels.
Proof positive in my book that women are the result of genetic damage.
I'm sure the power requirements are much lower, but yeah it's all about power level and exposure time. It could be handy for things that normally don't have anyone around, like runway lights that could light up with application forward looking radar or maybe something on the highway that could take advantage of the various auto-braking systems that are finding their way onto cars and trucks.
Tesla would be shaking his head in disgust.
do a wiki lookup on the "earth battery"; after that, jump over to "Wardenclyffe".
People really need to stop thinking that hertzian waves are the only thing under the sun.
Why, yes, I AM a Pagan Libertarian.