Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Dynamos & Power Plants - Question

  1. Jul 16, 2013 #1
    Dynamos & Power Plants -- Question

    Please Read!
    I know that cars need batteries to generate electricity to the dynamo to make the dynamo produce electricity continuously without stopping unless you switched off the car. The same to motorcycles. But I don't know whether the power plants do the same thing, so I need an answer for this question if you don't mind:

    Q: Do dynamos in power plants need batteries even if they're switched ON and producing electricity? If so, can't we remove the batteries from the dynamos after switching the dynamo on? Or do the "oil" and "nuclear reactants" do the work instead of batteries? Because I know that Dirt Bikes that have a "kick starter" can work without batteries via kicking the kick starter thingy to produce mechanical energy to the dynamo to make the dynamo produce electricity. But I heard that Cars cannot work the same as Dirt Bikes due to their "large engine and bla bla...", you cannot remove batteries from the car even if the dynamo is producing electricity so there will be no dangerous electricity going through the car. So I really wanna know, do power plants' dynamos have batteries or they work without them?
    Thank you!
     
  2. jcsd
  3. Jul 16, 2013 #2

    russ_watters

    User Avatar

    Staff: Mentor

    Cars don't need the battery when running - if they did, it wouldn't be possible to jump-start a car with a destroyed battery.

    In any case, power plants' generators have to be started but once started do not require external excitation.
    http://en.wikipedia.org/wiki/Excitation_(magnetic [Broken])
     
    Last edited by a moderator: May 6, 2017
  4. Jul 17, 2013 #3
    Then why do we use Oil and Nuclear Reactants for power plants to produce electricity? It was said that the "Oil has to be burnt to boil water and make steam, use the steam to drive a steam turbine, use the steam turbine to spin the electrical generator/dynamo to make electricity." And the Nuclear Reactors are the same.
    So I guess the Dynamo can't run without these things. Can you explain more if you don't mind?? Any more answers are appreciated and thank you for your informative answer!
     
    Last edited by a moderator: May 6, 2017
  5. Jul 17, 2013 #4

    russ_watters

    User Avatar

    Staff: Mentor

    Wait, what? Your first post asked if dynamos required batteries. That has nothing to do with the question of whether the prime mover requires input mechanical power! That's a completely separate question! The reason a generator requires input mechanical power is because a generator converts mechanical work to electrical energy. In other words, the force required to move electrons through a wire physically pushes against the generator's rotation.
     
  6. Jul 17, 2013 #5

    russ_watters

    User Avatar

    Staff: Mentor

    Ok, I see you have multiple threads open asking the same questions. Please don't do that. Thread locked.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Dynamos & Power Plants - Question
  1. Power plant generators (Replies: 1)

  2. Power plant generators (Replies: 20)

Loading...