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Energy going to waste

  1. Nov 16, 2008 #1
    With all the electric/hybrid cars becoming part of everyday life, I’ve been thinking about all the energy going to waste when ‘n vehicle has to come to a stop. Would it be possible to use alternators/generators to make use of that energy to make the vehicle come to a stop? As I understand, the more current being ‘pulled’ from an alternator, the more force the magnetic fields would try and stop rotation. Using current regulation would it be possible to control the stopping force, if an alternator was put on each wheel? Is this whole scenario plausible?

    Sorry for bad English (not my first language).

  2. jcsd
  3. Nov 16, 2008 #2


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    This is exactly what hybrids do. An electrical motor run backward is the same as a generator. It's called regnerative braking and gets back 50-75% of the wasted energy.
  4. Nov 16, 2008 #3
    Thanks, didn't know.
  5. Nov 16, 2008 #4
    I don't think hybrids really work. You are adding weight and complication.

    Better to have a small vehicle with an efficient as possible petrol/Diesel engine.. Eg .. Toyota Aygo (also badged as Citroen C1)
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