I have a little bit of a scientific background and would like to theorize if I could....

What about making a car engine where the engine is the secondary force involved, and the transmission is more the driving force, for the sake of energy efficiency?

I'm talking about using the principle of impulse momentum (ie the minimum force required to get an object moving), to charge hydraulics or whatever else, on startup, and then the transmission slowly releases such stored energy.

Think about this: a car powered by a bank of lawnmower pistons (bear with me here) that are there merely to work the hydraulics to charge the smart-transmission? Is this a workable idea?

  • you are envisioning the engine quickly generating all the power needed for an entire trip, storing that mechanically and slowly releasing it? Have you thought through the enormous amount of energy you need to store?
    – agentp
    Oct 28, 2017 at 13:33
  • What you are describing is basically the flywheel which is already a component in a modern engine. Essentially the engine drives the flywheel and the transmission picks up its drive from here. Nov 27, 2017 at 13:48
  • 1
    Series hybrids also work like this: the ICE charges a battery bank, and peak power output from the electric motor can exceed ICE output.
    – Hobbes
    Nov 27, 2017 at 16:43

1 Answer 1


Energy cannot be created or destroyed, only changed from one form to another and loosing some each time.

So you only get out what you put in less a little bit : if the impulse is 200W in 1 second then you can dissipate that impulse over a longer period of time as 10W for 20 seconds.

This is done already with stored energy flywheel systems for example and with hybrids : braking energy into batteries but the efficiency of these need improving...

  • You are correct about Conservation of Energy, but you may want to edit your details. I realize this isn't a physics site, but CoE is a little different than you've stated. Agree with what you're saying overall, though. And bottom line is, there's no free lunch. Oct 28, 2017 at 16:54

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