PopSci Predicts: The Year Ahead in Science and Technology

As a child, I played with a cap that had a wind generated propeller on top. It was just a novelty at the time, but it makes me now wonder, HUMMMM. Why doesn't the auto industry capture some of the energy from the wind gushing over the automobile as it goes forward? Put four or five air scoops with generators turning behind them to add additional miles to our batteries by recharging them as we go . We have regenerative braking, so why not add wind turbines in a scaled down version? It makes sense to me, and I'm not an educated technician.

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lenny--

There's a reason that "educated technicians" don't make such suggestions-- when you put a turbine blade on top of a car, it creates drag. If you hook it to a generator to give you electricity, it creates far more drag; the meager amount of electricity you generate can never be more than the energy you lose from that drag.

In YouTube you'll find a crackpot that converted a Mazda Miata to an electric car, and then covered the whole car with dozens of turbine generators just as you say. His little video pretends that it's "free energy", when in fact his car, aside from looking terribly silly and creating a hazard with all of its spinning blades, would be able to go much farther on a single charge if he removed all that hardware. Several times I posted comments to his video, saying that if he removes all that stuff and it does not get better range between charges that I would pay him $5,000, but after 3 years and several such posts by me, he has never even contacted me... he just keeps that inane video online. That should tell you something: There's no free lunch; perpetual motion does not work; if it did, he would have been trying to get me to collect on my challenge.

The reason regenerative braking works is because when you use the forward momentum of the car to generate electricity, it creates enormous drag, quickly slowing the car. If it did not, it would not help stop the car. What you propose doing would be exactly like driving with your regenerative brakes on all the time, which of course would mean your car would struggle to get anywhere.