Wireless Power Demonstrated 124
Necroloth and other readers sent in the story of Witricity's latest demo at the TED Global conference in Oxford, UK. The company is developing a system that can deliver power to devices without the need for wires. The idea is not new — electrical pioneers Thomas Edison and Nicola Tesla assumed that power would be delivered wirelessly. The BBC quotes the inventor behind Witricity's tech as saying that Tesla and Edison "...couldn't imagine dragging this vast infrastructure of metallic wires across every continent." eWeek Europe notes some hurdles the technology must overcome: "The 2007 experiment it is based on had an efficiency of only around 45 percent, but [Witricity's CEO] promised power delivered wirelessly would start out 15 percent more expensive than wires, and improve on that." Intel has also demonstrated wireless charging.
Wireless power has been around for a few years now (Score:3, Informative)
http://www.powercastco.com/ [powercastco.com]
They even won a best of CES 2007 award from CNET:
http://reviews.cnet.com/8301-12760_7-9673092-5.html [cnet.com]
They released working wirelessly powered Christmas tree lights in December 2007 as a consumer product!
http://news.cnet.com/8301-17938_105-9793204-1.html [cnet.com]
So this type of wireless power tech has been available in consumer products since 2007 and it appears that there has not been a lot of interest. I am really mystified as why nobody cares. Is it because they mistake this technology for some other kind of well known technology? I can't figure out the psychology here.
Re:Edison? (Score:3, Informative)
You can build a reasonably efficient resonant power transfer doohickey in your backyard out of some copper tubing, some low loss tuning capacitors, a RF power generator, and some diodes and filter caps on the far end to turn the received RF into DC.
I've built one to couple 4MHz pulses across to a rotating experiment for ultrasound measurement: http://n3ox.net/files/us_ring.jpg [n3ox.net]
You couple 'em that tightly, and they're like 99% efficient at transferring power.
But even with Tesla aside, this isn't new... it's just not as vastly useful as people re-discovering it seem to think it is. It doesn't work over gigantic distances, only moderate ones, and there's no engineering you can do to get around that. It's near-field coupling between resonant circuits. That said, I think it might end up pretty useful for non-contact charging of your electric car like TFA suggests. That's a *good* application for it, and it has more efficiency than "ordinary" inductive coupling.
As a physicist... (Score:5, Informative)
You'll be getting a memo from the Tesla Death Ray department shortly; Not observing it won't save you.
not all wireless power is the same (Score:5, Informative)
Full disclosure: I know Prof. Soljacic at MIT, who founded WiTricity, although I personally have no financial interest in the company; all of the above information is public and published, however.
Re:Thomas Edison ??? (Score:3, Informative)
Electrical pioneer my ass, he just got lucky once and was able to afford to hire good talent
Luck favors the prepared.
1869 Stock ticker
1874 Quadruplex telegraph [wikipedia.org] [Polar modulation]
Rights sold to Western Union for $10,000. [about $170,000 in 2005 dollars Historical Value of U.S. Dollar [mykindred.com]]
Menlo Park was in the business of invention. That in itself was a new idea.
1877 Phonograph
The most interesting thing about the phonograph is that no one saw it coming.
1880 Incandescent lamp.
Edison needed a lamp which could be wired in parallel. His team had to design every component - down to the wiring, fixtures, fuses and switches that would be safe for use in the home.