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(QUESTION I was Thinking of Creating a Generator System

  1. Oct 28, 2011 #1
    (QUESTION:) I was Thinking of Creating a Generator System....

    Okay, so I've been thinking about creating a generator system that doesn't reply on a Ful powered engine and to eventually get off of the "grid' completely one day... Also, in the last 4.5 years since we've moved into this house, we've lost power literally about 42 times as I've kept track after counting the first 10 in the first year...

    Bare with me here now....

    I currently have purchased a used 4kW (Rated) Fuel Generator. I would like to mechanically power the generator by an electric motor. I Have an electric motor that I wanted to power the generator with, that pulls 5.4a @ 120v, using a 3:1 pulley ratio to the Generator. To power the electric motor, I wanted to get a DC to AC upconverter that would more than handle the needed wattage of the motor that would be connected to a new 12v Automobile Battery.

    Now I understand that this would drain the 12v Auto Battery and that is why I wanted to have a second pulley on the motor that would also turn an Alternator to charge the battery. I do understand that I would have to possibly think about a new motor in the future that was large enough to power a larger Generator. As well as keep in mind maintainence on the motor and generator itself (i.e. Bearings, Brushes, Belts, Cables, etc...)

    Once I accomplish this, I wanted to actually start running the system 24/7 to a panel that I could either link to my Current breaker box via a transfer switch or completely remove the maximum amount of breakers from the houses current box to a new one that I could eventually switch my entire home over to, thus becoming completely free of our local power providers power and cost!!!?

    I'm looking for some advice on how to accomplish this task in due time, Without the opinions of the inexperienced and pesimistic forum users...

    Thanks in advance and sorry if that last statement was a bit offensive to anyone. That's not my intension. my intenstion is to realistically make this happen in an economically and safe way... Thanks!
     
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  3. Oct 28, 2011 #2

    f95toli

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    And where would the energy come from? Solar panels?
     
  4. Oct 28, 2011 #3
    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    If I understand your setup right, the following is what you want to do (the wattages and efficiencies I am going to use here are going to be made up, but in the ball park of correct).

    You are going to take a car battery that can produce 50W of power and run it through a DC to AC converter that has an efficiency of 80%. You now have 40W of power.

    You are going to connect the DC to AC converter to an electric motor that is 75% efficient (75% of your electric energy is converted to mechanical energy). This motor is going to be connected to a generator that is 75% efficient to get electrical power back out. You put 40W in to this system, you now get 40W * 0.75 * 0.75 = 22.5W out.

    Now you have to connect your alternator back to the battery... but at most it could be putting 22.5W back into the battery even though you are draining 50W. It may prevent the inevitable for a short period of time but you battery is still going to go dead.


    But the big picture:

    You started out with a 50W source and ended up with a 22.5W source. You would be better off just running off of car batteries to begin with. All you did was introduce a bunch of losses in the system without adding anything useful.
     
  5. Oct 28, 2011 #4

    russ_watters

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    You are making a classic mistake of thinking the generator requires little or no input mechanical power when in fact it requires slightly more than it outputs in electrical power. We get this question a lot here, so don't sweat it.
     
  6. Oct 28, 2011 #5
    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    12v Car Battery Connected to an "Upconverter" that typically plugs into a cars Cigarette lighter...

    Why wouldn't the (Automotive Type) DC to AC upconverter be able to be powered by the 12V car Battery? Isn't this what they are deisgned for? Am I missing a design step in between the 12v car battery to the wiring Harness of the car that has a Cigarette lighter on the end of it? The Upconverter that I'm looking at provides 1000watts. The Eletric motor is a 115v @ 5.4 which calculates to a consumption of 621watts of continuous power.If the upconverter is only efficient to 80% of the 1000watts then that puts it at 800watts.

    So how would an electric motor that requires 621watts to run and maybe 150watts more to start up (surge wattage) not be able to be ran off of this battery connected to this upconverter? Am I missing something here?

    And I think that you are missing the point here. What type of power the electric motor requires here has nothing to do with what the Generator puts out. The Rechanging, Bettery powered Electric Motor will be using a 3:1 pulley ratio to TURN the Generator Armature that has a Pulley on it... hence 3:1 ratio. The Ratio is a Guesstimate at this point but the point is that This will allow the 1750rpms of the Electric motor to turn the Generators armature much faster than 1750rpms (or whatever the proper ratio that it needs) therefore the generator head creating the Eletricity....

    I understand that Generator heads are a bit more tough to turn than a typical motors armature but there shouldn't be any reason that if my motor can't turn the pulley of the generator with the proper ratio and me giving it a good manual spin firt and then turnning it on, that I couldn't find a 120v eletric motor that does... no?
     
  7. Oct 28, 2011 #6

    DaveC426913

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    Mastiffman, you are aware that the only input of energy into this system is a 12 volt car battery, right? All your smoke and mirrors doesn't change that. You will get no more energy out if this thing than you would out of the battery. So what's with all the gadgetry?

    You're not seriously thinking you'll get more energy out than the battery can deliver are you?
     
  8. Oct 28, 2011 #7
    Re: (QUESTION:) I was Thinking of Creating a Generator System....


    How is it that a Man can use a Pulley System to lift something that is many times more weight than he can nomrally lift? Is that the same "Gadgetry" that you are spekaing of that I'm considering using? So are you implying that the Automobile DC to AC upconverters are all a hoax then?

    Would a Sketch help?

    [PLAIN]http://img831.imageshack.us/img831/103/possiblegenteratorconfi.jpg [Broken]
     
    Last edited by a moderator: May 5, 2017
  9. Oct 28, 2011 #8

    russ_watters

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    You didn't absorb what I said, so I'll say it again using your numbers:

    A 4kW generator converts 4kW of mechanical input power into 4kW of electrical output power, minus losses. A 621W converts 621W of electrical input power into 621W of mechanical output power. Obviously, 621W is much, much less than 4kW, so your motor is not capable of powering your generator.

    If you got a 4kW motor, you would be able to power your generator, but 4-4=0, leaving zero power surplus to power your house.

    You also may be operating on a faulty understanding of pulleys (also common). Pulleys obey conservation of energy: they do not magnify power. So a pulley setup with a 3:1 ratio will give an output of 3x more rpm and 3x less torque or vice versa. Since torque times rpm is power, the power stays the same.

    Note, perpetual motion is a banned subject on PF, but I've delayed locking this thread in the interest of helping you learn.
     
  10. Oct 28, 2011 #9

    russ_watters

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    It appears you think pulleys can magnify power. They can't. Please read up on the concept of mechanical advantage: http://en.wikipedia.org/wiki/Mechanical_advantage#Speed_ratio
     
  11. Oct 28, 2011 #10

    cmb

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

     
    Last edited by a moderator: May 5, 2017
  12. Oct 28, 2011 #11
    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    Okay I understand now... So what were to happen if I took a Brushless permenant magnet motor and spun that mechanically with a motor in this manner...?

    Here is video of what I was thinking but they didn't use my pulley idea or recharged battery idea....

    [crackpot link deleted]
     
    Last edited by a moderator: Oct 28, 2011
  13. Oct 28, 2011 #12
    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    Thanks for responding and I appreciate all of the comments and knowledge.

    This is basically what I'm looking for, a UPS. But in the aspect of eventualy creating enough to power my home one day. regardless of it's Efficient or not because it's all going to be machine based.... No?

    I just realized that I may used the wrong term here... I stated "CONverter" and think that I may have meant "INverter"...

    A) I'm not sure what the frequency has to do with the whole thing. I've not taken any classes on this stuff further than HS so I'm still in a constant learning state. (this may been the confusion and why you mentioned frequency....

    B) If the Battery can provide 12v power that can be CONverted into AC to power a Motor that recharges the battery AND mechanically powers a Generator or Permenant Magnet Motor, couldn't it be used as a continual source of electricity?

    C) This will not be powered by my homes electricity (grid)... I don't care if the power that I'm creating is "as" efficient as my local power plants, as long as I can eventually not have to deal with them at all...

    What type of HP would an electric motor need to power this Generator or any other then?
     
  14. Oct 28, 2011 #13
    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    So does the use of the term inverter Change things? or are you guys ignoring my ignorance? lol
     
  15. Oct 28, 2011 #14

    russ_watters

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    Re: (QUESTION:) I was Thinking of Creating a Generator System....

    The rules don't change.
    That is a hoax.
    No, what you describe is not a UPS. A UPS does not recharge itself.
    If the impossible were possible, the impossible would be possible, yes. But the impossible is impossible.

    This thread has run its course and is closed.
     
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