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A New Wireless Power Transmission Sheet

Posted by ryuzaki0 on from the electric-blanket dept.

Roland Piquepaille writes "Several companies have started to sell power 'pads' that can charge your cellphone when you put it on the pad's surface. But these silicon-based pads are expensive — and relatively 'specialized.' Now, Japanese researchers have built a plastic sheet which could power all the devices placed close to it. So far, this 4-layer sheet, which uses printed organic transistors and plastic MEMS switches, can deliver up to 40 watts of power — enough for some laptops. The technology is apparently efficient and inexpensive to produce. But as the devices to recharge will need to incorporate a special receiver, don't expect to see these plastic power sheets on sale before several years."

6 of 126 comments (clear)

  1. i remember this by brunascle · · Score: 3, Informative

    i remember this. good to see it's making its way to the market.

    1. Re:i remember this by OldeTimeGeek · · Score: 3, Informative

      If the brush that they're using is a Sonicare, there aren't any contacts - it uses inductance.

  2. Given his reputation... by Anonymous Coward · · Score: 1, Informative

    this one's tagged "fuckroland ohnoitsroland pigpail pigpile shill"

  3. How Efficient? by FroBugg · · Score: 4, Informative
    The article gives some efficiency numbers, but doesn't explain exactly what they're talking about.

    The researchers say the transmission of power happens with 81.4% efficiency -- compared to 93% efficiency in the wired grid network as a whole -- with a "quite low" level of leaked electromagnetic radiation.


    Now, I may be wrong, but I believe that 93% is the efficiency of electricity being generated at the power plant and then sent to you, however many miles away. So it's not an either-or thing, it's an extra loss. Instead of losing 7% of the generated electricity, you lose nearly 25%. This is ridiculous compared to the effort of just plugging your damn devices in.
    1. Re:How Efficient? by FroBugg · · Score: 2, Informative

      http://www.inference.phy.cam.ac.uk/sustainable/cha rger/

  4. Re:40 watts? by mobby_6kl · · Score: 3, Informative

    My laptop's PSU is rated 2.7 A at 18.5 Volts, and that must be with a good safety margin. Then agian, it's an almost six-year-old, 600Mhz P!!!-M machine, with 3D Rage Pro for video and an 11" screen.

    Mordern laptops, judging by the replacement PSUs available, seem to fall between 65-100W, although one Acer unit is rated at 135W.