On a clear summer day here in So Cal, my 16 300 watt solar panels can produce 30 KWH in a full day.
A basic electric now car has a 60 KWH battery pack to go a bit over 200 miles.
So in theory, full day of sun, with 16 large solar panels, you could drive about 100 miles. This is NOT portable by any stretch. Each panel is a bit over 1.5 Sq. Meters. x 16 = 24 square meters of solar panel, properly angled towards the sun. That is 4 meters by 6 meters. Put that to rough feet. 13.2 feet by 19.8 feet. So build that into a canopy and trailer to drag around with a Tesla.
Pyke,
If you push a generator with a motor, and use the generator to power the motor, you are making a perpetual motion machine. It does not work like that. Even with the latest tech, a fantastic generator is maybe 98% efficient, and the best motor might hit 98% efficient. But that still means, you are losing 4% of your power. The extra torque to spin the generator is more than the torque the produced electricity can provide. It is a lose lose. What electric cars, and hybrids do is they use the drive motor as a generator wen you apply the brakes. This works. As you slow down, the energy of forward motion is turned into electricity to charge the battery. Then you can use that power again when it is time to accelerate. Brakes on combustion engine cars just turn the energy of motion into heat and throw it away. In an electric car, the brakes put "fuel" back into the tank. OF course, you still get back less than you had to put in, but it is a lot better than not getting anything back. On a typical 400 mile tank of gasoline in my hybrid car, I regen over 10 miles of range just from braking. More in city driving, less out on the freeway.