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Substitute a gas motor with electric motor

  1. May 19, 2015 #1
    I'm sure that this has been posted before but....
    I want to substitute a gas motor in my 12kw Generac home backup generator with an electric motor 48-volt 4hp@4000 rpm series.. I would run this electric motor from the grid and power my home from this newly design generator.
  2. jcsd
  3. May 19, 2015 #2
    Why would you want to do that? Did you lose a bet?
  4. May 19, 2015 #3
    Correct me but the power consumption for a 48v motor that can propel a 12kw generator consume less power, I would thing 375 kwh/mo in turn costing me about 75.00 per/mo.
    This would be a big savings
  5. May 19, 2015 #4


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    Staff: Mentor

    So, I'm going to guess this is an attempt at a perpetual motion machine, but leave the thread up until confirmed. Trouble is, if you connect a 3kW motor to a 12kW generator, it'll just output about 3kW, and at a lower efficiency (say, 3.5kW input) than if you just used the mains electricity directly.

    But yes, we do get this question disappointingly often.

    [Edit: suspicion confirmed. Sorry, but the question is answered and we don't discuss perpetual motion here, even for debunking. Thread locked.]
    Last edited: May 19, 2015
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