electric conversion! anyone done it?

[Trisman]

some glaringly obvious reasons why it wouldn't work.

It's called the Second law of Thermodynamics!

Basically, it's why perpetual motion machines won't work.
You'd need something to be more than 100% efficient to power your motor/alternator/battery hybrid & that just can't be done!

When you factor in friction losses, the efficiency of ANY motor/generator, (plus the fact that can never even get 100% efficiency), it just won't work.

You can't get more energy out than you put in!


Anyhoo.. There is a guy who posts on YouTube who has converted various BMWs to electric power.

He's done an E46 3 series, an E39 5er (pretty successfully too, he uses it to get to work!) and is currently going to town on an E31 8 series.

Damian Maguire's Electric car conversions channel.

E39 test drive.

He knows his stuff!

I reckon it'd be easier to convert a RWD to electric power, getting drive to an FWD car would be harder...?

[clf]

Originally Posted by bikerdude666

I've always thought this, but never asked the question as I assumed there would be some glaringly obvious reasons why it wouldn't work. But I have always thought that an alternator or something connected up to the wheels would at least give some power back, to increase the range, even if it couldn't create enough to just keep on going.

I would say there is something or else it would have been done by now. Perhaps there is a limit to what can be harvested. I would imagine the Formula One KERS units could be employed also, and perhaps that in itself offers some kind of explanation. KERS is harvests the energy during the braking phases, ie high resistance situations.If the rotational motion could be converted to some kind of electrical power without affecting the overall power, I would have imagined it would have been utilised.

[keithst24]

Sooner hear my V6 rumbling to be honest

[bikerdude666]

Yea I get that you can't produce more power than you use, otherwise power stations would only need an initial kick to get them going. But surely there is/could be a way of creating a small amount to extend the range slightly?

All that aside, electric car's don't interest me at all, would much rather hear the noise of an engine.

I did look at the costs of an electric bike (just out of interest), and it would've taken 5 years just to break even, against a petrol bike, and restricted on range for pleasure rides.

[awvc1]

all the modern ev's and hybrids collect spare power from the braking systems. If you rig anything else up that takes from the drive mechanism, or in any way reduces your momentum, all you are doing is making your drive system less efficient I'd guess. You'll just have to start to accelerate again quicker.

[clf]

Originally Posted by bikerdude666

Yea I get that you can't produce more power than you use, otherwise power stations would only need an initial kick to get them going.

This is the bit I dont understand.I can appreciate that if the alternator was driven by a belt, there would be a drag, and inefficiency, however, if there was a shaft extending into the centre of the car, acting as the shaft of the alternator with the brushes acting on it. The brushes surely cannot create that much resistance/friction. The rotational input is always going to be there, so it must be possible to harness this. I know physics dictates that you cannot get somethign for nothing, but ...........

[Graham E]

I,m sure I've seen a magazine feature on someone who electrified an MGF

[Dorset Bob]

Originally Posted by Graham E

I,m sure I've seen a magazine feature on someone who electrified an MGF

Yes you are correct, it was actually an MGR development car.
http://www.autocar.co.uk/car-news/co...d-mgf-revealed

What could have been!......................

[zedziczek]

https://www.youtube.com/watch?v=n98ATylWi4g
http://www.fotowoltaika-szkolenia.pl...od-elektryczny

[chris75]

Originally Posted by clf

This is the bit I dont understand.I can appreciate that if the alternator was driven by a belt, there would be a drag, and inefficiency, however, if there was a shaft extending into the centre of the car, acting as the shaft of the alternator with the brushes acting on it. The brushes surely cannot create that much resistance/friction. The rotational input is always going to be there, so it must be possible to harness this. I know physics dictates that you cannot get somethign for nothing, but ...........

Borrowed from Wikipaedia .....

In physics, the law of conservation of energy states that the total energy of an isolated system remains constant—it is said to be conserved over time. Energy can neither be created nor destroyed; rather, it transforms from one form to another. For instance, chemical energy can be converted to kinetic energy in the explosion of a stick of dynamite.

A consequence of the law of conservation of energy is that a perpetual motion machine of the first kind cannot exist. That is to say, no system without an external energy supply can deliver an unlimited amount of energy to its surroundings

It's not just a question of friction on moving parts . The energy itself has to come from somewhere and unless your system is 100% efficient then you will need to put in more than you get out .So , if your power source is a battery then you will be draining the battery in order to produce your charging current That's why it won't work You can, and some vehicles do , have a secondary source like a small petrol engine / generator to top up , but then you are using petrol energy in addition . You pays your money ......