Okay so I have been moaning and groaning about this book I read over in the philosophy section, but here’s an Idea born out of that post.

Those who have a car know that the alternator changes the battery when the car is in motion. Okay so how about a super alternator which charges the whole engine, storing enough power in the battery to make the car go forward when you start it.

Science fiction or plausible

The idea of perpetual motion sounds so straightforward. An electric car powered by perpetual motion could recharge its own batteries forever, or a perpetual motion clock could automatically rewind itself for years. But there is a reason why perpetual motion machines remain in the realm of fantasy; it's the Laws of Thermodynamics. Some inventions may appear to run by perpetual motion, but they usually rely on a hidden source of external energy.

Both the First and Second Laws of Thermodynamics keep our perpetual motion car in the garage. According to one portion of the First Law, energy cannot be created or destroyed, only changed to different forms. The batteries which power an electric car only contain a fixed amount of energy. Most of this energy goes into propelling the electric motor, but some is inevitably lost through friction and the recreation of momentum after a stop. Our perpetual motion car's recharger would have to create even more energy in order to keep the batteries at full capacity. No such power generator exists, nor can one be built if the Laws of Thermodynamics are true.