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Power transmission through space

  1. Aug 17, 2011 #1
    If we had a source of power in space at some distance is there any feasible way it could be transmitted to the earth and converted to usable power here? Assume an almost unlimited source that can be converted to anywhere in the EM spectrum so efficiency is desirable but not required.

    The only thing that comes to my mind is light. Maybe a laser because it can be a relatively narrow beam. Intermediaries like satellites are ok too.
  2. jcsd
  3. Aug 17, 2011 #2
    There is a device called a rectenna, it converts microwaves to DC power. In the late 70s it was proposed to use the space shuttle to build large satellites that would use photovoltaics to power a microwave beam to the ground based rectenna.

    Supposedly the plan was efficient enough to be considered practical, but the expense of launching all the materials was and still is a deal killer.
  4. Aug 17, 2011 #3


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    Also, extremely dangerous if I recall. The concern was that you've basically got a microwave beam pointed at the Earth.

    If anything gets it in its way, or if the beam for some reason gets off-track, well, it being "hot enough to fry eggs on a sidewalk" would cease to be hyperbole.
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