

Wireless Electricity Demo - keltecp11
http://blog.ted.com/2009/08/wireless_electr.php

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modeless
This technology is not interesting to me. The efficiency is too low, the coils
are too big, the distances are too short, and too much alignment is required.
The talk of replacing batteries is just hype.

But the real reason I'm not excited is I don't believe this technology is
going to improve much. People look at this and think that it's just like
computers, so in 10 years these things will be 10 times smaller with 10 times
the range. That's simply not true; there's no Moore's law for wireless power.
We've known how to do this for over 100 years and the basic physics aren't
changing. In 10 years the coils will still be that big, with the same range
and the same alignment issues.

Batteries, on the other hand, have plenty of room to improve. In 10 years
batteries will definitely be storing more energy with less mass at lower cost
with faster charging and longer lifetimes. That's a technology I can get
excited about.

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sp332
Wireless doesn't necessarily mean remote. There are already power mats that
charge a cell phone that's resting on it, without having to plug in the phone.
I've even seen a prototype kitchen counter with a wireless blender - just set
the blender on the counter and it gets power.

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stcredzero
Countertops and appliances with this technology would be genuinely useful.
Wires and plugs are only a hinderance on a kitchen countertop. I can see this
introduced as a high-end luxury, then have it filter down into the mainstream.
Tables and other furniture with this tech would be great. Step in the door and
set your smartphone down on the stand, and it charges. Desks would be awesome.
Laptop stands would be great too.

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yread
I think nobody can really say if it is safe or not. Animals are sensitive to
magnetism - they can "see" where the north is. So it is not like magnetism
doesn't have effect on us. And saying that it is just like Earth's magnetic
field is downright wrong - that field doesn't have a MHz frequency and it is
nowhere near that strong. Besides with sufficiently high powered magnetic
field everything becomes magnetic <http://www.hfml.ru.nl/froglev.html>

I think I'll stick to the cables for some time

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mcav
How far could this technology reach physically?

He addresses proximity on a desktop and such; is it feasible to get the
magnetic coil to provide power within an entire house?

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dkokelley
I think the trick for now is to strategically position charging stations in
common areas (desk, bedroom table, kitchen, etc.). Also, it looks like
alignment is required, so it's not quite like the wireless router in your home
reaching all of the rooms, more like your TV remote reaching the TV set.

~~~
Locke1689
Right. I'm nowhere near an expert in this but I would guess that the receiver
has to be orthogonal to the planar field lines (parallel to the rectangular
transmitter). Mostly that's a guess though because I'm not sure I understand
how the magnetic resonance works, however he does seem careful to place the
devices in that alignment.

~~~
blackguardx
Resonant energy transfer has been known for a very long time. Any electrical
system that has inductance or capacitance (which means all electrical systems)
will have a resonance point. This resonance point is the like the resonance
point of a mass spring system or like resonance of a pendulum in a grandfather
clock. If you drive a system at its resonance point, you will maximize the
energy transfer into the system. That is all that is going on. If both the
send and receive coils resonate at the same frequency, maximum power transfer
can occur. There is no magic. This isn't a technology.

Also, the coils do indeed have to be parallel to each other. Fields gradients
are function as vectors in space and the receive coil must be positioned to
"capture" as many field lines as possible emitted from the transmitter.

~~~
Locke1689
OK, thanks. That's what it sounded like but his description was low on the
details so I figured I wouldn't make that stretch. Anyway, yes, my guess was
mostly based on Maxwell and a little vector calc (physics minor, nothing more)
but it seemed to make sense.

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dkokelley
Does anybody know about the commercial availability of such a system?

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devicenull
Those were my thoughts exactly. I'd buy this now and I'm sure other people
would as well. The quicker they get this to the market, the better.

~~~
keltecp11
Invest in recycling plants... there is going to be a lot of cable taken down
and given a new life... this technology is amazing.

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keltecp11
I expect this within 10 years. This might be the 'next big thing'

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yread
Hope is luggage doesn't get "lost" on the way back to US ;)

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xcombinator
Oh please, don't risk my health even more!!!

Because it's not enough to have so much contamination, smoking, diesel
particles, polymer additives, pesticides, nuclear waste,mercury fillings,
let's add even more.

Because you are too lazy to make a hole for your TV once in your lifetime, you
add something that radiates 50% of their energy out there. YES, it's
radiation, no matter what this pseudo scientist say(don't try to fool ignorant
people), it's an electromagnetic wave, it is not static = radiation. This
energy are photons of big wavelength.

1mW-3miliWatts laser light could be dangerous, let's put 50-400Watts(look at
TVset specs)and radiate 100-800Watts out there(2·10^5 times more energy). What
could go wrong??

Just do it, profit and if people get cancer, it's very difficult to prove. For
the people that says that this can't resonate with cells and so on, look at
the size of your brain, is that an electrical system? could it be affected in
any way , look at your spinal cord, your testicles-ovaries(the size of the
cell phone)...

Don't get me wrong, People here are young and healthy, but I have seen people
die very very bad from cancer - leukaemia after working near telecom towers(20
from 40 got cancer, the company make an statistic using the total company
workers "diluting" it and saying that it's an statistic atypical, that it has
nothing to do with their work). When my father worked in chemical industry as
a chemist, when all the workers in one place lost their teeth they(the
company) said that surely the workers got a venereal disease or something
their fault.

If someone dies or is affected from this thing, they are going to say: hey, it
can't be our system.

I don't care about people using this on their own taking responsibility, I
care about people using it near me, or my family(neighbours), invading my
airspace and polluting it.I care about systems capable of radiating 40KWatts
for powering electric trucks (hey, it's safe!!) on public roads and I don't
want it. Let me chose.

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CamperBob
_YES, it's radiation, no matter what this pseudo scientist say(don't try to
fool ignorant people), it's an electromagnetic wave, it is not static =
radiation._

When you can explain the terms in this simple equation:

    
    
         E = hv
    

... we'll all be interested in your opinion on this subject.

~~~
xcombinator
I don't understand the question.

Do you mean that the energy that carries each photon is quantized (when the
energy state of the excited atom is quantized in orbitals) and is inverse
proportional to the wave length?

¿That is not radiation because it bounces a lot and don't penetrate?

If you use a lot more photons, you will have a very different effect that a
single one.

Also, if you start making this devices, you will make it smaller and smaller
and use less L on the inductances because it's more efficient, and that means
use bigger frequencies, even microwaves( I heard they were using far radio in
the first experiment), that are going to resonate with molecules bonds like
ADN and stuff.

~~~
CamperBob
_If you use a lot more photons, you will have a very different effect that a
single one._

No. You will not. That's exactly why I sent you to the library with that
equation.

