

Tesla's World Wide Wireless Power Tower - wolfish
http://www.damninteresting.com/?p=703#more-703

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AndrewO
I've heard so many stories of the much abused and misunderstood Tesla, usually
coming from people I'd politely call "free-energy wackjobs". Even this
article, which is one of the fairer versions I've heard, doesn't touch on why
this has never been implemented or experimented upon further. It can't be for
lack of interest or ignorance or for startup cost either (or else I'm sure YC
would have funded someone to build these towers).

So HN, anyone with more electrical knowledge than I know why this doesn't work
or why it wouldn't scale or any other engineering challenges that have kept
this from being more than a pipe dream?

~~~
electromagnetic
Main problem, electricity arcs to ground ASAP. This means that the system can
basically only have two connections in range of each other, so 1 power plant
to 1 user. The economics of this doesn't really work well.

Generally electricity only arcs once, and it requires 30kV/cm. This means to
arc to two things at 10 cm you require about 600kV, but again this requires a
small amount of energy to be transferred to ground.

Transferring through the ionosphere would likely resolve some of this problem,
it's like dipping electrodes into salt water. It works, it's just omni-
directional and subject to the environment. However, you basically have to
build every antenna 50km high.

The technology I believe is credible, but the practicality of it isn't very
high. Below the ionosphere this technology has the problem that the ground is
usually much closer than the next persons house. This would work great above
100 ft, due to the fact that the whole ozone production would poison most
people. Above 100 ft, I can only transmit power in a range of less than 100
ft, but generally only to one person. If I want to transmit to two people it
has to be below 50 ft.

At 100 ft the voltage limit is 90 million volts before you're arcing directly
to the ground. The safe limit would probably be 45 million volts as you'd be
arcing to peoples heads at 90 million volts.

Basically how the system would end up breaking down is that you'd use hundreds
of feet of cable to connect to your antenna, which we currently use less to
connect to the one down the road. I believe mine is about 30 feet away. The
substation would require a few thousand feet or so of cable to connect to the
main transformer, again which we use considerably less to do today.

So the only practical usage I see is on the long distance scale, where you're
using the ionosphere instead of arcing through the air. However, it would all
have to be over 100km apart. Yet at such extremely high voltages to be
practical we wouldn't have a strong enough insulator to stop the arcing
anyway.

Unless we end up with like 2 power stations in North America and a super
electrical insulator, I doubt this technology would ever become truly
practical.

~~~
trapper
Do you have a blog about your projects?

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racerboy
I remember reading this when it was originally posted to DI's site a couple
years ago. Pretty cool stuff, I'm sure some folks here who haven't read this
will appreciate it. DI truly has some Damn Interesting articles!

~~~
scorxn
Ah yes, a staple from the golden age of reddit. Anyone know why they haven't
written anything since October?

~~~
Element
I think they stopped posting while they work on their book but I could be
wrong.

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buugs
I had a wonderful physics teacher who brought in a bunch of different
inventions made by Tesla and I always thought they were interesting but the
theory of wireless electricity is so different to people it always blows my
mind that it works ,despite all the physics attributed to it, if this becomes
popular soon we will have to find a phrase to replace "plugged in."

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wlievens
Tower of Power reminds me of Frank Zappa :-)

