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Hello,
I was wondering if I could just add an alternator to an ev and get a range extender. The alternator seems like a good idea, even an industrial one, now... I have no knowledge in this area whatsoever, so would anyone enlighten me?

{Note From The Administrators:
This has now become the official thread for all questions relating to using alternators/generators WITHOUT AN EXTERNAL POWER SOURCE. Call it free energy/perpetual motion/ over-unity or whatever you will. If you have a question about a series hybrid or range extender (with an ICE engine) then feel free to ask start a new thread, if you want to know about the other kind then please read this thread and the wiki first before asking questions. Cheers, mattW}
 

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Re: alternator as a range extender attachment?

An alternator need to be driven to produce energy. Also like any other energy conversion technology, it needs more energy coming in than it will produce.

So where is this energy coming from? I hope not from the battery pack. Since it'll take more energy than it produces, it'll run that battry pack down faster than if you didn't have it at all.

Gas or diesel? Now you're getting somewhere. A series hybrid is essentially this type of system. A diesel genset generates power that drives the electric motor or charges the batteries.

ga2500ev
 

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Re: alternator as a range extender attachment?

Hey, apparently alot of people bring up this idea about some kind of alternator or generation system to take advantage of the car's forward movement in order to extend the range. I should know, I'm one of those people lol. It would be great, but the general consensus is that the actual generation of electricity, the movement of electrons in the coils, basically creates an electromagnet that makes drag, effectively making it harder to move the generator the more power you're generating.

Here's the thread I started - http://www.diyelectriccar.com/forums/showthread.php/2-basic-questions-13043.html - These guys are really smart and have helped me think this through, but basically my thought is that if you changed the curve of your generation coils to maximize your capture of the spinning magnetic field, it might also eliminate that radial drag factor and even get it to move faster per power drain instead of the other way around. It would be like a figure-8 circuit, with one set of magnets effectively repelling the other by-proxy of your coiling. There's alot of mights there, so I've got plans and parts to build the thing and I'll be keeping people updated. But until that happens, I'd listen to the conventional wisdom of these guys.
 

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Re: alternator as a range extender attachment?

Well, I have been considering the "micro diesel" approach that would run off of waste vege oil or biodiesel. This would power A/C, PS, and alternator to charge may be 12 v system and provide current to 144v system, not sure about dc-dc conversions though. This would greatly extend the range of the vehicle (depending on the fuel tank and engine size). there are small diesel generators that you could rob the engine from. Also diesels on mowers as well.
 

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Re: alternator as a range extender attachment?

Well, I have been considering the "micro diesel" approach that would run off of waste vege oil or biodiesel. This would power A/C, PS, and alternator to charge may be 12 v system and provide current to 144v system, not sure about dc-dc conversions though. This would greatly extend the range of the vehicle (depending on the fuel tank and engine size). there are small diesel generators that you could rob the engine from. Also diesels on mowers as well.
A diesel lawn mower? That would be the perfect engine to harvest and turn into a generator. Good idea. The only mowers I know of in NZ are 2 and 4 stroke petrol engines unfortunately.
 

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Re: alternator as a range extender attachment?

A diesel lawn mower? That would be the perfect engine to harvest and turn into a generator. Good idea. The only mowers I know of in NZ are 2 and 4 stroke petrol engines unfortunately.
Yes, I saw one at an auction here and I was REALLY tempted to snap it up, but didn't have a project for it. Now, I have a project and no engine :)

I have also seen small diesel generators that would work great.

BTW great work on the videos. I enjoyed them!

Mark
 

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Re: alternator as a range extender attachment?

Here's a picture of the mower

afterthought, it might be a tad big for my application... not "micro" sized, although I have seen some that are.

 

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Re: alternator as a range extender attachment?

I calculated my daily driving to be less than 50 miles so I don't think the added complexity is worth it for my first car.
 

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Re: alternator as a range extender attachment?

Hello,
I was wondering if I could just add an alternator to an ev and get a range extender. The alternator seems like a good idea, even an industrial one, now... I have no knowledge in this area whatsoever, so would anyone enlighten me?
To answer your question:

If you mean adding an alternator that's powered by the electric motor of the EV, then simply no, it will not work.

This is what you call Perpetual Motion and according to all the laws of physics it is impossible.

You can never get more energy out of a system than you put in.

A simple experiment to do yourself, goto the local hobby store buy two small 6 volt electric motors, link their shafts together then wire them together.

Now try spinning them, they will not continue to spin.


A normal gasoline car's alternator takes energy away from the spinning engine to produce electrical energy, but this is not 100% efficient.

In order to obtain Perpetual motion you need a system that is more than 100% efficient, which is impossible.

EDIT: I think I should make a wiki article on this, seems I've written this nearly 20 times now.
EDIT: Here it is:
http://www.diyelectriccar.com/forums/showthread.php?p=40555#post40555


EDIT: I forgot to mention.

If your referring to an Alternator that is powered by a gasoline/diesel engine as a range extender, then yes, this can work, this is what is called a Series Hybrid.
 

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Re: alternator as a range extender attachment?

I respect that such a thing doesn't exist yet, but that doesn't mean it never will. Perpetual energy or perpetual motion is not impossible, since by the very definition magnets themselves are perpetual energy devices (though they slowly lose charge over many years). The blockage I think is a mental one and not necessarily a physical one... most people seem to look at the magnetic drag as an inevitability of nature and throw up their hands, and make little to no attempt to thwart it (provided they even get that far in their thoughts..). My disagreement isn't so much with the practicality of this statement, that perpetual motion is impossible, but with its theoretical basis - because if you look around at the energies and forces that keep this little world spinning you'll see that's just not the case. It's our technology that has to catch up to the Universe, not the other way around. If we can split atoms and forge particular vortices and build the internet, then someone somewhere someday should be able to make a generator with no electromagnetic drag. The technology hasn't really changed much in the last century, it's a mystery to me why this particular hurtle has remained for so long.. But nevertheless, never say never. :p
 

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Re: alternator as a range extender attachment?

I've never heard of this electromagnetic drag, but even overcoming it doesn't overcome the fact that whatever energy you are getting from the alternator is coming from the moving wheel, which is getting its energy from the battery. So you are taking energy from the battery to give back to the battery, but you are wasting little bits of it along the way when you convert the elctricity to movement and heat, then to friction and movement, then from movement and friction back to electricity. That friction and heat are not trivial, and don't add up to negative amounts of energy, which is what you would need to wind up ahead.
 

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Re: alternator as a range extender attachment?

since by the very definition magnets themselves are perpetual energy devices (though they slowly lose charge over many years).
If magnets slowly lose charge, over time, (which you agree with) then they are not an unlimited source of energy.
 

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Re: alternator as a range extender attachment?

MrCrabs, over the course of a century or two yeah, especially if you used some strong neodymium magnets. I don't mean 'perpetual energy' in the sense of running virtually 'forever', but for all intents and purposes it would still probably last a lifetime at least.

Weelliot, the electromagnetic drag is caused when you actually start generating electricity with conventional generators, effectively making it harder to move the more power you generate. This is to be expected though from that coil geometry. It stands as the major hurtle to regenerating power this way, but if you crossed that hurtle there wouldn't be anything stopping you from at least making some attempt to gather power back from your vehicle's motion. I'm not discounting friction, or wobble, or heat, I know those are all factors but again even if you got 75% of your power back that makes for a significant added range.
 

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Re: alternator as a range extender attachment?

Hey Guys!
I just have to say something about a magnet being a perpetual energy device..if a magnet is a perpetual energy device then so is any spring or a broom stick for that matter.It is just a property that seems "magical".You can not recycle its energy.You put a piece of steel in front of it that it pulls with whatever force untill it arrives on the magnet then what? You have to spend a lot greater energy to pull the steel off of it and you can do it again. In that analogy I have lots of perpetual energy hooks in my walls holding pictures for years now...anyways sorry this thread got a little sidetracked. Barna:)
 

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Re: alternator as a range extender attachment?

You guys are the ones who've got me roped into the perpetual motion montage... I don't really want to prove perpetual motion, because theoretically it wouldn't be perpetual motion. That's given, fine, written in the stones, whatever I don't give a damn. I don't ascribe magnets any special magical properties, like you say it's just a magnet, and it does hold and emit a constant force, but if that constant limited force could be translated into forward spin then you would have a vehicle with a limited amount of constant forward thrust equal to how much magnet force you use. You could have a circuit that essentially would last as long as the permanent magnets themselves (which is a long damn time), with help from various other sources like wall jacks and solar to make up for losses from starting/stopping, heat and that sorta thing. Again, only if you made some clever alterations to the existing charging/drive systems and made a design of generator geometry that made magnetic drag into magnetic help, would this be possible. This should be something everybody who can should be investigating, not something to be scoffed at... And if it does work, it should be open source so anybody can build it! Don't you think cars should work more like wall hooks? Good analogy indeed... :p
 

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Re: alternator as a range extender attachment?

Attention members, admins, et al:

This question, and numerous variations keeps coming up over and over. The answer is always the same. Can we get a sticky post explaining this? I'm sure it's in the wiki somewhere, too.

You can't extend the range of an EV by adding any kind of generator/alternator if it's powered directly or indirectly through the motion of the car. It's ALWAYS a loss. The Laws of Thermodynamics have stated this for years. A lot of people that seem otherwise intelligent keep asking this, and it winds up as a multi-page post with the more scientific types explaining that this leads to the whole perpetual motion thing, which is of course impossible.

The only useful application would be to recover energy during braking, but you don't need a generator or alternator for that - a motor controller with regen braking will do that for you.

You can always dream up creative "exceptions". If I put a wind turbine on the roof of my EV, then sat at a stoplight on a windy day, yes, I'll generate more power than I use. But that's just wind power, and you're not using the car's power (or motion through the air, which comes from the car's motor) to move the turbine. The list goes on...

Do we need a vote?

-Mark
 

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Re: alternator as a range extender attachment?

What if you lock the wind generator when the batteries are already full??
The answer would be a computer controlling he charge of the batteries and constantly enabling and disabling the turbine which could fit on the sides of the car or on the low part of the front bumper.
Just a thught, but then the answer is a generator just does not work.
Thank you.
 

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Re: alternator as a range extender attachment?

Magnets do not give any energy they only provide a force which converts energy from one form to another. To get one magnet to push another magnet you need to move them closer to each other so that their magnetic fields interact. The force they exert on each other is the same or less than the force it took to move them together in the first place. Its not free energy/over-unity/perpetual motion its just a force, like gravity, which can store and convert energy from one form to another.

Electrically you can move electrons into a magnetic field (by moving the wire or using current) and the magnets will push the electrons perpendicular to their motion. If the wire is moving through the field it will push the electrons along the wire, converting the kinetic energy of the wire into electrical energy in the electrons. That is a generator. Or you can convert the electrical energy of the current in the wire into kinetic energy to push the coil. That is a motor. It is a simple efficient energy conversion. Don't bother thinking about electro-magnetic drag or anything like that, it is more of an illustration than the physics itself... All you need to think about it energy conversion, the best you can get is all of the kinetic energy ending up as electrical or visa versa.

Free energy/over-unity/perpetual motion is impossible in the universe we live in, I'm not saying it is hard, or untried or too expensive... it is physically impossible. It is exactly the same as creating your own atoms out of thin air (E=mc2). You are just as likely to create your own distinct universe as you are to get efficiency greater than 100%. I don't mean to be dramatic, I'm just trying to help you understand, some things are impossible and this is one of those things.

Wirecutter- there is a wiki article (two actually, here and here, no one ever checks before starting articles lol.) about this but I'll consider making a sticky too.
 

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Re: alternator as a range extender attachment?

Free energy/over-unity/perpetual motion is impossible in the universe we live in, I'm not saying it is hard, or untried or too expensive... it is physically impossible. It is exactly the same as creating your own atoms out of thin air (E=mc2). You are just as likely to create your own distinct universe as you are to get efficiency greater than 100%. I don't mean to be dramatic, I'm just trying to help you understand, some things are impossible and this is one of those things.

Wirecutter- there is a wiki article (two actually, here and here, no one ever checks before starting articles lol.) about this but I'll consider making a sticky too.
Speaking of making microscopic distinct universes...

I'm agreeing with everything you're saying, and I don't know why we're arguing at this point. Like I said, magnets are nothing magical, they're just constant producers of a certain amount of force. Force can be used to create energy or electricity, and electricity can be converted back to force. It's nothing new, in fact it's all the same principles that go into electric motors and generators today. The only difference is some clever re-engineering of the geometry to turn it into something that would be as if you were holding those magnets close together, and you won't deny that that force exists. As you said, magnetic force becomes electricity and electricity becomes magnetic force, so a circuit can logically mediate that same force between the magnets and put it to work (with losses of course, but I've acknowledged that). Once again I'm not going over 100% - 100% would be the maximum magnet force available and you literally couldn't go higher than that. Again again, I'm not shooting for over-unity, perpetual motion or anything, not snatching atoms out of thin air, just taking another look at how we're using these wonderful things called magnets.
 

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Re: alternator as a range extender attachment?

Content posted previously by me was retracted after further research determined author (me) doesn't know his arse from a hole in the ground. :) Norm
 
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