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Earth as a Generator?

  1. May 16, 2007 #1
    Would it be theoretically possible to use the earth's magnetic field to generate electricity? Essentially, my idea is that if we link large enough coils together in orbit (not geosynchronous) we would have enough energy to run the world many times over and not have to use any fossil fuels whatsoever. How would we be able to transmit that amount of energy to the surface of the earth?
  2. jcsd
  3. May 16, 2007 #2


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    Read up on the Tether experiment performed by NASA. But its for the purpose of powering space stations an not "run the world". There simply wasnt enough energy.
  4. May 16, 2007 #3


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    The earth's magnetic field is, in fact, extremely weak. The amount of metal you'd have to put in orbit to induce any significant amount of current would be unfathomable. We'd use more energy as fuel getting all that wire into orbit than it would ever recoup.

    - Warren
  5. May 16, 2007 #4
    To extract electricity from a static magnetic field the pick up coil would have to cross the magnetic lines by moving or rotating. However, eddy currents in the pick up coil would oppose the static magnetic field and exert a force and torque on the pick up coil. As the force or torque is exerted, the pick up coil would keep slowing down in motion. So the satellite orbiting the planet with large pick up coils would slow down and eventually crash. But the amount of electrical energy extracted is far less than the energy it took to launch the satellite into space. So you are back to square one.
    Last edited: May 16, 2007
  6. Jul 26, 2008 #5
    There is plenty of energy, the earth has vast supplies of it. What do you think the power of a lightening bolt represents? The earth is magnetic, has a north pole and a soulth pole and is essentially like a gigantic electric generator spinning in space. The power is there, all we need to to is discover how to tap into it. Nikola Tesla did it in Colorado. We can do it too.
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