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Wireless Electricity

  1. Jan 31, 2009 #1
    I came across an interesting story today and thought I would share it here.

    Wireless Electricity

    Neat stuff.

    Although I do wonder, even if they get it working and feasible for large-scale adoption, would there be any adverse health affects? (I sometimes read articles in magazines like "Popular Mechanics" and "Popular Science" about how groups are considering producing power in space and beaming it down to Earth as microwaves. I don't think I'd feel comfortable living in a large microwave oven. Or being surrounded by RFID devices. Or living under power lines. etc.)
  2. jcsd
  3. Feb 1, 2009 #2


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    Science Advisor

    MIT has been working on that for a while.



  4. Feb 1, 2009 #3
    I think health concerns will be a major issue here and because of the necessity of some sort of power focussing any applications will be limited to static components.
  5. Feb 1, 2009 #4
    I doubt the efficiency can ever be very high. There are losses in converting from AC-DC, DC-RF, coupling loss, RF-DC and maybe DC-AC.

    Makes a lot more sense to just run a wire and have no conversions or just one; AC-DC.
  6. Feb 1, 2009 #5


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    Staff: Mentor

    Charging pads will no doubt be an expanding market, though I think a limited one because of one critical problem: people won't want to carry around the charging apparatus attached to their cell phone all the time. Power transmitted across the room to power a laptop computer? Never going to happen. It is far too inefficient and again, you'd need a couple of pounds of coils or a big dish attached to the back of your laptop for it to work at all.

    For health concerns, low frequency EMF (power lines) have none. Microwaves obviously have some, particularly for the space-based power station idea.
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