why can’t electric cars be charged by their own movement?

Question

why can’t electric cars be charged by their own movement?

In: 14

Answer 1

cars with that type of charger built-in can top up the battery by rolling steeply downhill for tens of km. a lot of movement to produce a little current. some people aren’t connected to a reliable high voltage grid. they have to generate their own electricity and they appreciate just how inefficient it really is.

only with modern engineering do we get some current with relatively little effort. and even then, it takes a lot of movement to get a little current.

we can ask a related question; “why can’t i keep my cellphone fully charged using a compression device built into my shoe-heels”.

and the answer is; “we can! but, just like the gravity powered car that must roll downhill constantly, so we would have to walk everywhere constantly.”