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Typing Recharges Laptops?

Posted by CmdrTaco on from the sounds-crazy dept.

TwoSticks writes "Compaq patents a keyboard that captures your kinetic energy. Magnets and coils on each key charge a small battery to augment the big one in your laptop. Standard NYTimes deal: requires free registration. " I'm a bit suspicious but it looks interesting. It might give me an incentive to fix typos anyway ;)

1 of 140 comments (clear)

  1. Estimation by amonymous · · Score: 5

    I'm not going to use a keyboard that requires
    me to apply more than 5 newtons to a key.
    Let's say the key course length is about 2mm.

    That's 10^-2 J per keypress, neglecting the losses
    in transformation from mechanical to electric
    energy.

    You need 10 keypresses to get 0.1W of power for
    1 second.

    Forget about having your notebook run on that
    alone. Keyboard power is somewhere between
    "little influence" and "neglectable".

    Could be more practical for a PDA without a
    hard drive, but then the trend for these things
    is not to have a keyboard at all.