just an idea
Thread Starter
Registered User
Joined: Jun 2009
Posts: 333
Likes: 0
just an idea
so I was thinking, the same way a windmill or a watermill charges a battery, why couldnt someone invent an electric car that uses the non-drive wheels to charge the batteries? you would never have to plug it in to charge, you could literally drive forever and never have to stop for gas or to charge. anyways im sure if it was possible someone wouldve done it by now. but if it could be done it would be pretty awesome
Registered User
Joined: Feb 2003
Posts: 1,824
Likes: 0
Physics doesn't quite work that way. Nobody's managed to build a "perpetual motion" machine that doesn't require some power to keep it moving.
If you have an electric car, some of your electric power is lost to heat in the motor's brushes and bearings, in the car's driveline and all of its bearings, the friction of the tires, aerodynamic drag, etc. Energy is lost just in the process of accelerating and maintaining speed.
On the flip side, if you then put a generator on the non-drive wheels, it won't be 100% efficient, either. You'll recover "some" energy, but still lose more to friction and heat.
But, while it can't be COMPLETELY done, if you look at a modern electric/hybrid like a Prius, they DO recover battery power under deceleration by effectively reversing the electric motor and using it as a generator. Google "regenerative braking" to learn more.
If you have an electric car, some of your electric power is lost to heat in the motor's brushes and bearings, in the car's driveline and all of its bearings, the friction of the tires, aerodynamic drag, etc. Energy is lost just in the process of accelerating and maintaining speed.
On the flip side, if you then put a generator on the non-drive wheels, it won't be 100% efficient, either. You'll recover "some" energy, but still lose more to friction and heat.
But, while it can't be COMPLETELY done, if you look at a modern electric/hybrid like a Prius, they DO recover battery power under deceleration by effectively reversing the electric motor and using it as a generator. Google "regenerative braking" to learn more.
__________________
buildin' it
Joined: Aug 2006
Posts: 4,565
Likes: 0
loren to the rescue again.
the problem with using the non drive wheels to power the car is that you'll never make enough power to keep the car going.
However, the crafty people would suggest that wiring up/setting up an alternator to be powered by one of the wheels, and that alternator then charge a battery/bank of batteries would in turn assist with gaining additional range before the charge ran out.
Seems like a valid arguement, but I have yet to see anyone actually pull it off.
Hell, I've never even seen someone work out the math to even see if it is as good of an idea as it sounds.
I know from experience that alternators, while not perfect, can generate a decent amount of voltage without taking a whole lot of horsepower away, especially once it gets started.
I would imagine it would be too complicated to run that kind of system on a production car, but would be interesting to work out/try out on a project car.
the problem with using the non drive wheels to power the car is that you'll never make enough power to keep the car going.
However, the crafty people would suggest that wiring up/setting up an alternator to be powered by one of the wheels, and that alternator then charge a battery/bank of batteries would in turn assist with gaining additional range before the charge ran out.
Seems like a valid arguement, but I have yet to see anyone actually pull it off.
Hell, I've never even seen someone work out the math to even see if it is as good of an idea as it sounds.
I know from experience that alternators, while not perfect, can generate a decent amount of voltage without taking a whole lot of horsepower away, especially once it gets started.
I would imagine it would be too complicated to run that kind of system on a production car, but would be interesting to work out/try out on a project car.
Thread
Thread Starter
Forum
Replies
Last Post
