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Q & A: No fueling around

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Most recent answer: 01/05/2012
How can I make a car which will make use of no fuel?
- emmanuel (age 19)
It always takes some sort of energy to run a car.  That energy can come from various sources: hydrocarbon fuel like diesel or gasoline, or hydrogen, or electricity from a battery or solar panels, or from wind.    You always need something.


and  hydrogen or batteries have to get their energy from some other source, since there aren't significant amounts of hydrogen gas or charged batteries lying around.
Mike W

(published on 08/06/2008)

Follow-Up #1: water as fuel?

Is it possible to make a car which uses water as fuel?If yes than how
- KANISHK (age 14)
No, not in any normal sense of the words. "Fuel" means a source of free-energy. In the environment that automobiles operate in, that typically means some substance that can lower its free energy by combining with oxygen in the air. Water can't do that. It's already in its lowest free-energy chemical form, in the context of the car's environment.

Of course in principle some of the nuclei in water could be used as fuel for a fusion nuclear reactor, since they're not in the lowest possible nuclear state. However, that's not even remotely close to being achievable.

So long as we stick to chemical reactions in an ordinary environment, water isn't fuel.

Mike W.

(published on 01/05/2012)

Follow-up on this answer.