Go Down

Topic: How tall can we build? (and Voltage Differential of Earth) (Read 1 time) previous topic - next topic

cjdelphi

NASA generated electricity by sending up rockets with a rope attached too them, basically my feeble (compared to Lord Grumpy Mike)  understanding of it was between Earth, or rather Ground, now if we go high enough we have the Positive magnetic field, now as a result, electric charge and indeed a good amount of current began to  flow.

Let's suppose they build massive high what's the limit, steal rods, glad rods even (just because of amount of sand) send them high sky, right up high, then drop down to ground Teathers...

Question is, can we build, i say we, i'll never personally, but the Human race as a whole or rather the few who think they possibly could even if they could not..... be that Graphene, or Carbine or just Toughened Glass, would this not just be the purest way to produce energy?


mmcp42

once built you may have a case
but the green debt of building such a thing would need to generate a lot of electrons to be green neutral methinks :)
lots of Brownie points for lateral thinking :)
there are only 10 types of people
them that understands binary
and them that doesn't

kf2qd

Te problem is that this voltage differential is rather variable. ANd can rech quite high voltages. It is normally released in what we call lightninig. Launch a model rocket with a fine wire attached and you can cause teh lightning to hit the launch point. Problem is, that's an awful large amount of energy being released. Many years ago Popular Science had an article about static electricity motors. Problem was, getting a reliable voltage level was a challenge... Changes in weather can really screw things up...

westfw

I thought the NASA project worked by dragging a conductor through the earth's magnetic field, which you can do if you're in orbit at an appropriate altitude.  But if you're attached to the earth like a building, you're static WRT the magnetic field, so no electricity generation occurs.  (This is particularly neat, because you can also run it backward - run a current though a long wire connection two satellites, and you can make it change altitude!)
http://www-spof.gsfc.nasa.gov/Education/wtether.html

There's also the electric field differential that people are talking about, but it normally tends to be very low in POWER (while the voltage can be quite high.)  Suitable for running electrostatic motors, perhaps, but those tend to be low power devices as well.  And the altitudes involved to get significant voltages are already achieved by today's buildings; it's about 100V/meter!
http://en.wikipedia.org/wiki/Atmospheric_electricity

radman

What you really need if you want power is a Dyson Sphere to generate ~4 x 1026 W . If you cannot build that then keep up with the intergalactic neighbours by at least getting a half decent Dyson-Harrop Satellite;
http://www.lpi.usra.edu/meetings/abscicon2010/pdf/5469.pdf

Another essential is a space elevator. The problem with building that is that all known materials will be crushed under their own weight. However if you put a lump of rock into orbit round the Earth you could "drop" a line from it and keep it under tension rather than compression. Not sure how this stands up to winds etc. or what would happen if somebody cut the rope!

robtillaart

Quote
or what would happen if somebody cut the rope!

the moon would fly away ? ;)
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

AWOL

Quote
NASA generated electricity by sending up rockets with a rope attached too them

Reference?
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

cjdelphi


Quote
NASA generated electricity by sending up rockets with a rope attached too them

Reference?


Google is your friend.

SirNickity

Kind of an obtuse search string.

Q:  "nasa generating electricity rockets ropes"
A:  http://en.wikipedia.org/wiki/Space_tether

Is that it?  Otherwise, maybe you could ask Google to friend AWOL?

Boffin1

I recall seeing the experiment on TV where they winched out the wire from the the shuttle , and the winch sparked and packed up.
They tried it on another shuttle trip and generated quite a bit of voltage.

E&OE :-)
With my mobile phone I can call people and talk to them -  how smart can you get ?

AWOL

Quote
NASA generated electricity by sending up rockets with a rope attached too [sic] them,

Quote
Google is your friend.

Which failed to find examples - Google, you're no friend of mine.

Satellites with tethers, I've heard of, but not rockets.

"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

Boffin1

I remember buying military surplus micro fine twin wire from guided missiles, many moons back, I wonder if any voltage was generated if they were fired from aircraft.

Not that they would have been using 3v3 Vcc on the logic in the TSR2 days, it was all good old transistors.
With my mobile phone I can call people and talk to them -  how smart can you get ?

radman

Quote
I remember buying military surplus micro fine twin wire from guided missiles, many moons back, I wonder if any voltage was generated if they were fired from aircraft.


I am sure a voltage would have been generated. When they work on overhead powerlines they diconnect them but also earth them as wind blowing through the cables can generate enough static to be dangerous.

On a bit of a tangent there is a video on youtube of a guy climbing out of a helicopter to work on a live overhead line!

The satellite wire works because the wire is moving through the Earth's magnetic field - great idea, wonder who thought of it.

The Dyson-Harrop Satellite uses the solar wind.


Boffin1

Quote
The Dyson-Harrop Satellite uses the solar wind.



I was once quite excited about solar sails, until I saw the figures -

The L'Garde solar sail will produce a maximum thrust of approximately 0.01 newton, which is roughly equivalent to the weight of a "pink packet" of artificial sweetener.

even if the satellite has only a few Kg mass, I will be long dead before it gets anywhere interesting :-)


With my mobile phone I can call people and talk to them -  how smart can you get ?

radman

The Dyson-Harrop Satellite does not rely on the push of the solar wind instead it extracts electrical energy from the plasma
Quote
A relatively small Dyson-Harrop satellite using a 1-centimetre-wide copper wire 300 metres long, a receiver 2 metres wide and a sail 10 metres in diameter, sitting at roughly the same distance from the sun as the Earth, could generate 1.7 megawatts of power - enough for about 1000 family homes in the US.
http://www.newscientist.com/article/dn19497-outofthisworld-proposal-for-solar-wind-power.html

Apparently it is practical to build one of these the main issue seems to be how to get the power from the satellite back to Earth using lasers. No doubt it is not quite that easy but "This satellite is actually something that we can build, using modern technology and delivery methods," Harrop says.

Go Up