Beam electricity from solar panels above the clouds?

[garybeck]

As a solar energy engineer, many people have asked me, "why can't we put solar panels up in the atmosphere above the clouds?" I've always replied, they don't make extension cords long enough, and we don't have technology to "beam" electricity through the air. Rumors are Nicola Tesla had developed a way to do this but many of his inventions remain a mystery.

However, researchers at MIT might be on to something:

MIT researchers said Thursday they will soon be able to charge a computer or cell-phone battery from across a room, perhaps making the annoyance of wires or dead batteries a thing of the past.

Massachusetts Institute of Technology scientists and their wireless energy transfer technology may soon eliminate wires that tether our machines to wall sockets, or may keep batteries topped up and ready to go.

"This invention could free us from power cables and ideally replace batteries to a good extent, at least in the context of a home or office setting," said Aristeidis Karalis, a student member of the MIT team that worked four years on the problem.

The team at MIT, a top US academic laboratory, has shown their fledgling "WiTricity" technology can power a 60 watt bulb from a power source two meters (seven feet) away.



http://rawstory.com/news/afp/Wireless_power_may_cut_some_wires_b_06072007.html

[Speck Tater]

1. Quick! Let's rush into this without knowing anything about long-term health effects.

Next thing you know we've inadvertently sterilized the whole human race.

[garybeck]

2. relax, it's just an interesting article, not a plan. :) n/t

[oldgrowth]

6. P.D. James Children of men,just read the book

[skids]

3. At 40% efficiency? I think not...

...even if they could get the distance up that high and still maintain that efficiency level.

[garybeck]

4. this is just the beginning.

40% efficiency on the first pass is pretty good. give it 20 years and see what happens. i'm not saying this is the answer. it's just interesting to see they've done it.

[skids]

8. Well, Tesla did it a long time ago...

...really I think you can read a lot into what the MIT folks are
saying about its potential applications. They are talking about
using it to charge PDAs while they are still in your coat pocket.
I'd say they probably know the theoretical limitations of the
system and they aren't too horribly concerned about the efficiency
problem because they don't care about energy waste, they just
want to exploit the fact that "WiTricity" is a cool thing that
appeals to technophiles who are too lazy to plug their PDA in.

In case you want to read more about it, the phenominon used
is called "evanescent wave coupling" and one of the basic
limitations to it is preventing power loss from waves that
radiate instead of being reabsorbed into the antenna. That and
resistive losses in the copper, which would be helped by using
a superconductor if we had such a thing as a cheap one of those.

[Redstone]

5. Not scalable. Also, no birds or airplanes in the transmission path. So let's not

expect microwave power beamed down from satellites any time soon, OK?

Redstone

[Common Sense Party]

7. Just as long as I can charge my iPod without plugging in.

Especially on the airplane. I could just point it at the sun...

[OKIsItJustMe]

9. Microwave transmission ...

... or laser has been proposed for years...

http://en.wikipedia.org/wiki/Solar_power_satellite
http://gltrs.grc.nasa.gov/reports/2004/TM-2004-212743.pdf