How does a dynamo produce electricity?

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    Dynamo Electricity
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Discussion Overview

The discussion centers around the functioning of dynamos and their role in electricity generation, particularly in vehicles and power plants. Participants explore the relationship between magnetic fields and electricity production, the necessity of batteries in different contexts, and the mechanics of how dynamos operate.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants inquire about how dynamos produce electricity and the role of magnetic fields in this process, questioning whether electricity can be generated without a magnetic field.
  • There are questions regarding the use of oil in power plants and how steam is utilized to generate electricity.
  • Participants discuss the operation of dynamos in vehicles, particularly whether a car can run solely on a dynamo without a battery.
  • Some contributions clarify that moving an electrical conductor through a magnetic field induces current, and that dynamos convert mechanical energy into electrical energy.
  • There is a distinction made between the operation of dynamos in cars and power plants, with some participants questioning why batteries are necessary in cars but not in power plants.
  • Participants mention that while a battery stores electricity, it is not required for a dynamo to produce energy, as the dynamo can generate electricity based on mechanical motion.
  • Some responses reference Faraday's Law to explain the principles behind electricity generation in dynamos.
  • There is a discussion about the differences between dynamos and alternators, noting that modern systems often use alternators which produce AC electricity.

Areas of Agreement / Disagreement

Participants express various viewpoints on the necessity of batteries for dynamos in different applications, leading to unresolved questions about their roles in vehicles versus power plants. The discussion remains contested with multiple competing views on the mechanics and principles involved.

Contextual Notes

Some participants express confusion about the basic principles of electricity generation and the specific mechanics of dynamos versus alternators, indicating a need for clarification on these topics. There are references to external resources for further exploration of the concepts discussed.

John231
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Hello guys, I have a few questions to ask and I really need an answer for them all. Firstly, I know that the Dynamo or the Generator produces electricity to the vehicle engines and houses, etc... But I seriously want to know how Dynamos produce electricity exactly. I didn't understood exactly how magnetic field inside a dynamo produces electric impulses or electricity. I want to know what is the relationship between the production of electricity and magnetic field. And whether the electricity can be produced if there was no magnetic field in a dynamo. So look at these other questions:

Q: Do we use "oil" for power plants to produce electricity? If so, how? And I don't know what people mean when they say "steam" moves the windmill or blades bla bla bla...

Q: If the battery of the car switched on a Dynamo, can we remove the battery of the car before switching it off and drive the car via a dynamo only?

Q:
 
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Q: When the dynamo is switched on, it produces electricity automatically without the need of a battery? Because I recently saw some videos of people manually produce electricity by dynamos via their Kinetic Energy. So what's the difference?
Thanks!
 
John231 said:
I want to know what is the relationship between the production of electricity and magnetic field. And whether the electricity can be produced if there was no magnetic field in a dynamo. So look at these other questions:
At the simplest level, moving an electrical conductor through a magnetic field creates a current flow in the conductor. (This is a huge oversimplification, but it's good enough to get you started). Thus, a dynamo and similar devices that generate electricity work by using mechanical energy to move magnets and conductors (typically by mounting them on a spinning shaft).

Q: Do we use "oil" for power plants to produce electricity? If so, how? And I don't know what people mean when they say "steam" moves the windmill or blades.
Burn the oil to boil water and make steam, use the steam to drive a steam turbine (google for "steam turbine"), use the steam turbine to spin the electrical generator/dynamo to make electricity.

Q: If the battery of the car switched on a Dynamo, can we remove the battery of the car before switching it off and drive the car via a dynamo only?
You cannot, but it's not because the dynamo isn't capable of making enough electricity flow, it's because standard auto electrical systems expect the battery to be there to help smooth out any voltage fluctuations in the output of the dynamo.
 
Nugatory said:
At the simplest level, moving an electrical conductor through a magnetic field creates a current flow in the conductor. (This is a huge oversimplification, but it's good enough to get you started). Thus, a dynamo and similar devices that generate electricity work by using mechanical energy to move magnets and conductors (typically by mounting them on a spinning shaft).Burn the oil to boil water and make steam, use the steam to drive a steam turbine (google for "steam turbine"), use the steam turbine to spin the electrical generator/dynamo to make electricity.

Ok, does a dynamo in a power plant has a battery? Or that is only in cars? If so, why?

You cannot, but it's not because the dynamo isn't capable of making enough electricity flow, it's because standard auto electrical systems expect the battery to be there to help smooth out any voltage fluctuations in the output of the dynamo.

You mean by "smooth out any voltage" is to prevent dangerous voltages coming out from the output of a dynamo?
Ok, but how will it not work without a battery? The Dirt bikes already work without batteries if they had a "kick starter" that start the dynamo with mechanical energy as I think.

Thank you I really appreciate your informative answer and waiting for your latest answer as soon as possible!
 
*** And does a dynamo in a power plant works without batteries? If so why? Why does a dynamo in PP works without batteries and cars do?
 
Or the Oil and other resources like Nuclear reactors are used instead of batteries in Power plants?
 
John231 said:
You mean by "smooth out any voltage" is to prevent dangerous voltages coming out from the output of a dynamo?
Not dangerous to people, but dangerous to the car's electrical system - this thread from BITOG covers most of the ground: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1983065

Ok, but how will it not work without a battery? The Dirt bikes already work without batteries if they had a "kick starter" that start the dynamo with mechanical energy as I think.
Yes, as do lawnmowers and many other small-engine devices. It doesn't take terribly sophisticated electronics or precise voltage control just to operate a spark plug, and an older pre-electronics-era car will probably run OK without a battery. But a modern car all loaded with computers to drive the fuel injection, time the sparks, work the ABS brakes... Not so much.
 
Nugatory said:
Not dangerous to people, but dangerous to the car's electrical system - this thread from BITOG covers most of the ground: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1983065Yes, as do lawnmowers and many other small-engine devices. It doesn't take terribly sophisticated electronics or precise voltage control just to operate a spark plug, and an older pre-electronics-era car will probably run OK without a battery. But a modern car all loaded with computers to drive the fuel injection, time the sparks, work the ABS brakes... Not so much.

*** And does a dynamo in a power plant works without batteries? If so why? Why does a dynamo in PP works without batteries and cars do?

Sorry for asking too much but you really make me understand how dynamos are working.
Thanks!
 
  • #10
A battery doesn't produce electricity, it just stores electricity. And because a car's engine doesn't produce mechanical energy at a consistent rate, the alternator doesn't produce electrical energy at a consistent rate, so it is useful to have the battery to store the energy to prevent spikes. But that has nothing at all to do with whether a battery is required for the generator to produce energy - it isn't.
 
  • #11
John231 said:
*** And does a dynamo in a power plant works without batteries? If so why? Why does a dynamo in PP works without batteries and cars do?

I think you have a more fundamental issue here. I'm going to direct you to a principle known as Faraday's Law, where a changing magnetic field can induce a current in a wire.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/farlaw.html

Make the connection to the fact that a dynamo has a magnet, and a coil of wire surrounding it, and one of them has to be moving to produce current.

Zz.
 
  • #12
John231 said:
*** And does a dynamo in a power plant works without batteries? If so why? Why does a dynamo in PP works without batteries and cars do?

Sorry for asking too much but you really make me understand how dynamos are working.
Thanks!

Can I go back to basics, because you are still asking the same question? A dynamo uses a magnetic field and this can be produced with a permanent magnet or an electromagnet. An electrical voltage in a coil is induced (produced) when the magnet rotates (moves) relative to the coil. The elecrical energy comes from whatever is providing the turning motion, (you don't get anything for nothing) such as a wind turbine, steam turbine, hamster wheel. Most 'dynamos', these days are actually Alternators and produce AC, which may be rectified (as in cars) or used directly (as in AC Power Plants).
Simple alternators use a permanent magnet but bigger alternators (in power stations or in cars) use an electromagnet because it is easier to regulate the output voltage to suit the demand (how many devices are switched in). The energy for an electromagnet (or rather the Power needed) is not much and, before the alternator is turned up to speed, it is supplied from an external source, a battery, or, in the case of a massive power plant, it can be a 'donkey generator' (which is a small, additional generator and which may, itself have a battery). The system has to be able to pull itself up by its own bootstraps.
Once the alternator is up to speed, it supplies current to charge the battery, to produce its own magnetic field AND to supply the load it's there to supply.
 
  • #13
sophiecentaur said:
Can I go back to basics, because you are still asking the same question? A dynamo uses a magnetic field and this can be produced with a permanent magnet or an electromagnet. An electrical voltage in a coil is induced (produced) when the magnet rotates (moves) relative to the coil. The elecrical energy comes from whatever is providing the turning motion, (you don't get anything for nothing) such as a wind turbine, steam turbine, hamster wheel. Most 'dynamos', these days are actually Alternators and produce AC, which may be rectified (as in cars) or used directly (as in AC Power Plants).
Simple alternators use a permanent magnet but bigger alternators (in power stations or in cars) use an electromagnet because it is easier to regulate the output voltage to suit the demand (how many devices are switched in). The energy for an electromagnet (or rather the Power needed) is not much and, before the alternator is turned up to speed, it is supplied from an external source, a battery, or, in the case of a massive power plant, it can be a 'donkey generator' (which is a small, additional generator and which may, itself have a battery). The system has to be able to pull itself up by its own bootstraps.
Once the alternator is up to speed, it supplies current to charge the battery, to produce its own magnetic field AND to supply the load it's there to supply.

Hello, thanks for your informative beneficial answer! But I wonder do "fully Electric-powered Vehicles" have dynamos to charge their batteries? And if they do, there will be no more wall-charging?? Or it will only charge for only some miles/kilometers?
Waiting for your answer as soon as possible!
Thank you!
 
  • #14
John231 said:
Hello, thanks for your informative beneficial answer! But I wonder do "fully Electric-powered Vehicles" have dynamos to charge their batteries? And if they do, there will be no more wall-charging?? Or it will only charge for only some miles/kilometers?
Waiting for your answer as soon as possible!
Thank you!

No. That would be a nonsense. The Energy has to come from somewhere. What would a Dynamo achieve if it were powered by the vehicle batteries? You always have to put more energy in than you get out of anything. You would, effectively, just waste some of the energy stored, originally, in the batteries.
You have to have "wall charging" or an alternative source of power (an internal combustion engine, usually), which consumes Fuel.
What you are suggesting is a Perpetual Motion Machine, which my Grandfather embarrassed me by proposing when I was at school in the late 50s. He also was surprised, later, that we couldn't hear the 'Satelloon' when it went overhead - (look it up). Old geysers let you down so often!
 
  • #15
It is interesting that in Jules Verne's novel "Twenty Thousant Leagues Under The Sea", the Nautilus is run on batteries but nothing is ever said about how the batteries are charged! Verne himself seemed to think that batteries created power (or perhaps he just couldn't figure out how to reasonably charge them and just ignored the question). It was only in the "Disney Version" that there was the implication that nuclear power on a secret island was used- which led to the first nuclear submarine being named the "Nautilus"!
 
  • #16
sophiecentaur said:
No. That would be a nonsense. The Energy has to come from somewhere. What would a Dynamo achieve if it were powered by the vehicle batteries? You always have to put more energy in than you get out of anything. You would, effectively, just waste some of the energy stored, originally, in the batteries.
You have to have "wall charging" or an alternative source of power (an internal combustion engine, usually), which consumes Fuel.
What you are suggesting is a Perpetual Motion Machine, which my Grandfather embarrassed me by proposing when I was at school in the late 50s. He also was surprised, later, that we couldn't hear the 'Satelloon' when it went overhead - (look it up). Old geysers let you down so often!

Sorry for asking too much, you know that Dirt bikes (internal combustion engine) which have a "kick starter" start engine without batteries. And cars (internal combustion engine) usually have batteries. So... What's the job of "Fuel" or "Petroleum" in cars? I'm really curious and interested to this topic! What I guess about "internal combustion engines cars" is that: when you start up the car, the battery has to produce the stored electricity in it to power the dynamo and the dynamo powers the engine so that the combustion process is applied; then "FUEL" will react very highly by compressing it, so that to produce to the dynamo "Mechanical Energy" to power the dynamo. Like the Power plants use Oil to be burnt to boil water to create steam to move the turbines... Is that right? If I'm wrong correct me if you don't mind and thank you for sharing your answer!
Waiting for your answer!
 
  • #17
sophiecentaur said:
No. That would be a nonsense. The Energy has to come from somewhere. What would a Dynamo achieve if it were powered by the vehicle batteries? You always have to put more energy in than you get out of anything. You would, effectively, just waste some of the energy stored, originally, in the batteries.
You have to have "wall charging" or an alternative source of power (an internal combustion engine, usually), which consumes Fuel.
What you are suggesting is a Perpetual Motion Machine, which my Grandfather embarrassed me by proposing when I was at school in the late 50s. He also was surprised, later, that we couldn't hear the 'Satelloon' when it went overhead - (look it up). Old geysers let you down so often!

And Electric-Powered Vehicles don't have fuel so there's no big reaction is happening to transfer the Mechanical Energy to the dynamo to power the engine. I think that's it...
 

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