Perpetual motion

[C1ay]

What wasn't? & wasn't what?.

 

The thread wasn't moved to "Tutorials and How To's"?

 

Even geothermal is somewhat touch'n'go.

 

Nope. Even geothermal energy won't last forever so motion that uses it is not really perpetual. OTOH, it might provide one source of energy that will last as long as we're around. Then again, so would the sun and the moon.

[Qfwfq]

I was referring "touch'n'go" to:

Everything can be linked to the sun. All the atoms were at one point part of the sun, or derrived from other atoms that were, even the radioactive ones. So inherrently every form of ebnergy is essentially solar with that argument.

 

Barring the "creationist" view of solar based energy, the only other form of energy that is not derrived as such would be geothermal or nuclear. (Perhaps one could argue tidal action as a source but that is gravitational which again stems from the sun).

[Xenosis]

From what i understand of the Electrodynamic tether (or whatever the exact name of the effect is) you are not really getting that energy for free, you are sucking it away from the earth's rotation. So in the shortterm and small scale it is perfectly fine, but if you created a large scale generator or used it extensively you could eventually stop the earth or its magnetic field :) which would be kind of bad...of course it would probably take thousands of years..but still, I wouldn't want that to even come close, i would rather have a big gaping hole in the ozone first :)

 

But all this info is a bit old and dusty, I think it has been about a year since i read the artical in Scientific American that talked about this.

 

I don't think we will see any perpetual motion machines working off conventional forces and energy source, if one is created it would probably be from something like the "strings" that were mentioned earlier, or some other quantum effect. Otherwise you are just pulling the energy from some other source.

[Qfwfq]

...you are not really getting that energy for free, you are sucking it away from the earth's rotation.

Certainly, and quite obvious, either from Earth's rotation or from the orbital kinetic energy. I haven't worked it out, I would need to know the exact setup.

 

Tidal dissipation is sucking rotational kinetic energy, whether we exploit it or not, and certainly more than a few tethered generators could do.

 

To be reaping a huge amount from the rotational kinetic energy, the tether would have to be subject to a large tangential force, causing problems in maintaining the orbit anyway.