I have a nice idea, although maybe not so usefull. Since space shuttels are in vaccum when in space, the gravity is neglectable, and also the friction (no air). So a great way of producing electricity in space is by raotating the magnet of a simple power generator, prfebly with no main axis(even less friction). Then, I think, almost every bit of the energy will be converted into electricity. And for those who wonder why this idea isnt just free energy (as i did) - well thats because any electrical flux will create a magnetic field, and this is the only kind of force (not really friction) that will act i this system (dont know how to put this in english, hope you understand).-- Icarus, Apr 09 2001 the physics of levitron http://www.levitron.com/physics.htmlpossible magnetic bearing/rotor? [mihali, Apr 09 2001, last modified Oct 04 2004] flywheels as energy storage - wired magazine http://www.wired.co.../8.05/flywheel.html [mihali, Apr 09 2001, last modified Oct 04 2004] I think he's saying that a spinning magnet in space is more efficient at transforming kinetic energy into electricity (this doesn't actually generate any power, since the energy needed to keep the magnet going will be greater than the electrical output) than a spinning magnet on Earth, if you forget about the costs of getting it there in the first place and maintaining it once it is there.-- bookworm, Apr 09 2001 why not use magnetic bearings? this = no friciton. see the link for more info.
if i understand icarus correctly, he/she wants to use the magnetic properties to keep the rotor spinning, and also to induce a current in a winding around that rotor.
the second link is a wired magazine story on using flywheels in a vacuum as energy storage devices, which is a similar idea.-- mihali, Apr 09 2001 PS you're quick on the draw!! you didn't even give me a chance to post those links!!
i'd say that this idea is in the semi-baked category, with a slightly different flavour.-- mihali, Apr 09 2001 Not so much Baked as Pointless (unless I misunderstand terribly).
Frictional losses in the generator of a power plant are negligible, compared to the inefficiency of whatever turns that shaft in the first place. You'll still need the actual power plant to run that generator, which you haven't specified at all. The cost of moving anything into space (today, at least) is enormous; gaining such an almost imperceptibly tiny smidgeon of efficiency won't even begin to make up for that.
There are some reasons to generate power in space; this is not one of them.-- egnor, Apr 09 2001 egnor, we're not talking about perpetual motion or violationg the laws of thermodynamics. this excerpt from the wired story may help:
'...The underlying concept is simple, though the finished flywheel assemblies become increasingly complex. First you feed electricity to a motor, which accelerates the wheel to cruising speed. Riding on magnetic bearings inside a vacuum container that eliminates air resistance, the wheel can spin almost indefinitely after you cut the power. When you want to tap its energy, you draw electricity back out of the motor, which now functions as a generator. This imposes a load on the wheel, gradually slowing it as mechanical energy is converted back to electricity.
US Flywheel already has a prototype wheel running at more than 60,000 rpm, designed under contract for NASA, to replace batteries in the International Space Station....'
power generation will always be inefficient, but this seems to be a more efficient way of doing it than other methods that have been suggested/designed/built.-- mihali, Apr 09 2001 Hello again. I think most of you misunderstood my idea. The idea was for a shuttel, or maybe a space station, in need of producing power in space, will use this idea, and not for producing power for our planet). I didnt mean that it will be more efficient to move whole powerplants to space. Also, i only proposed a mechanism for improving the generator itself, not the mechanism of revolving the shaft. Further more, part of my idea was that there will be no friction between the shft and the rest by simply not attaching them (although that maybe a little hard, keeping them in relative balance when moving, but thats another problem).-- Icarus, Apr 09 2001 (flim flams drums-crashes cymbal)-- thumbwax, Apr 10 2001 random, halfbakery