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I will be the first to admit that I have no clue what I am talking about here so don't yell at me if this is a stupid question.
I know Tesla recently came out with the dual electric motor setup but before they did that I was thinking about the fact that all that rotational energy from the front wheels was essentially being wasted. Would it be possible to, instead of putting a motor in the front, put a generator in the front or run the front motor in reverse all the time so that as you drive you are drawing energy to power the rear motor but simultaneously using the front wheels' motion to generate electricity to recharge the battery. I realize that is basically what you are doing with regen braking, but my question is could you have it do that all the time? Or do the laws of physics just go NO and then proceed to give you a dope slap for even suggesting such nonsense?
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Generators don't spin freely with no effort. To generate electricity with them, they have some resistance to turning--it takes force to spin them around. In the application you are talking about, you can't just add a generator and not affect the motion of the car. The generator would slow the car down, or would require you to press the accelerator down harder, using more energy, just to keep up your speed. That is exactly why they use it for regenerative braking--generating any electricity with it slows the car.
Remember that motors/generators just convert energy from electrical to kinetic or vice versa. The idea you are proposing is some conversions in a closed loop. Battery - motor - car motion - generator - battery. Motors and generators are at best a bit over 90% efficient, so any extra energy that you pull from the battery to put into car motion and then try to grab it back to put back in the battery is getting converted twice, and you lose about 10% each time, so the system would be running itself down just from that, not even considering wind resistance, tire friction, etc.
So yeah, that's been thought of, but it is called a perpetual motion machine, and it provably cannot exist.
You obviously could do regen while driving just like you can brake while driving, but doing that you would lose a lot more than you gain. You just deplete your battery faster.
We can't create energy, nor can we destroy it. We can only convert it to different forms. No conversion is ever perfect, so in each conversion you lose some to non-usable forms of energy.
A generator is simply a means of converting kinetic energy (energy from movement) to electrical energy which we then usually store in a battery. The process gives off heat (energy) due to friction of bearings etc mostly but other forms as well which results in loss of storable / usable energy during that process. All else being equal the fewer energy covertion steps we have the higher the efficiency of the whole system. No cheating is allowed or will work. This is the result of the law of entropy.
Therefore this process cannot be even be100% efficient, let alone gain energy from nowhere. This is a zero sum process and some energy always leaks away leaving you with less total usable energy to use than you put in.
If you want more energy you have to grab it from outside of this local system.
That would work, but you have to hope that their aim is perfect every single time.
...following Danfos Turbo cor....magnetic bearings...a small trailer...could hold a small generator...charging on the GO...Has anyone put a trailer hitch on a Tesla...In case you are in a prolonged power outage and need to get out of town...solar cowboy
So no the car is not set up to run off an auxiliary ....power....unit.....
Huh?
Or not.