Re: Threading a moon

Erik Max Francis skreiv:

That would be true if the conductors were being launched and then
electromagnetic interactions were causing them to fall back down.
Instead, what appears to be described is creating the conductors on
Callisto, launching them into Jupiter orbit (i.e., escape velocity from
Callisto), and then letting electromagnetic interactions to sap their
potential energy _with respect to Jupiter_, not Callisto.

Yeah. But I can't imagine it's that impressive. Making copper-bars with
lasers on them will consume energy, as will launching them from Callisto.

Escape-velocity from jupiter is 60km/s or so, so at best, the energy
released is the same as the energy required to accelerate the
copper-bars to 60km/s. Minus the energy used for mining, transporting,
refining etc the copper. Minus the energy for making and installing the
laser. Times the efficiency of the laser and receiver.

One kg of copper could produce 500Kwh, if it fell from infinity and
everything was 100% efficient. In practice I think you'd be lucky to get
10% overall effiency out of this scheme.

At which point it makes sense if 50Kwh is worth more to you than a kg of
copper. Doesn't sound like a good deal to me, even assuming there where
huge amounts of easily accessible copper on Callisto.

*Certainly* doesn't sound anything at all like "huge amounts of
near-free energy".

I think someone was confused and thougth that the strong magnetic fields
of jupiter makes the energy huge, when in reality the energy is limited
not by that, but by the gravitational potential of whatever you drop at
jupiter.


Eivind Kjørstad
.

Relevant Pages

  • Re: Does electron acceleration cause Radiation Absorption?
    ... energy state, it requires an input of energy. ... A higher shell is not a higher velocity. ... the same as the velocity of the atom... ... meters per second in a copper atom but it's drift velocity is in mm ...
    (sci.physics.relativity)
  • Re: copper benzoate- how easy is it to make?
    ... benzoate and I'm wondering if the addition of copper ... guess the carboxyl to be less electron-donating than the nitro group, ... if the energy hump of that change is lowered by the presence ...
    (rec.pyrotechnics)
  • Re: Are nukes the answer to global warming?
    ... replaced with low energy cost manufacturing. ... world reversing the trend and going copper to save money. ... >& consumption, ...
    (sci.energy)
  • Re: Lightning Ball ???
    ... energy. ... Have a large balloon go up about 1,000 feet,and have a copper ... wire attached to the ground so that this could make a good conductor. ...
    (sci.physics)
  • Re: Threading a moon
    ... its kinetic energy into electricity. ... That would be true if the conductors were being launched and then electromagnetic interactions were causing them to fall back down. ... Instead, what appears to be described is creating the conductors on Callisto, launching them into Jupiter orbit, and then letting electromagnetic interactions to sap their potential energy _with respect to Jupiter_, not Callisto. ...
    (rec.arts.sf.science)