Of course, using water to power a car is just a pipe dream. We all know that water can't "burn" like traditional fossil fuels, and any attempt to extract energy from water in other ways will eventually be dashed.
The water molecule contains three atoms: one oxygen atom and two hydrogen atoms, which are tightly bound together like magnets. Professor of mechanical engineering and director of an automotive lab where he studies engine performance and emissions, combustion science and energy conversion says it always takes more energy to break those bonds than you get.
Suppose you want to build a vehicle that can run on water, it needs equipment to break down water molecules and separate oxygen and hydrogen. They then need to be isolated separately in separate tanks.
Then you need a combustion system that can mix and ignite them, or a fuel cell that can put them back together to generate electricity. The energy released can then drive the piston or run the motor and move the car.
The question is this: "The water molecule is very stable. The energy required to separate the atoms is greater than the energy returned, and this process actually absorbs the energy, rather than releasing it.
In addition, there is a more volatile problem: hydrogen is flammable. If you don't have the right safety measures, you might be in a traffic accident.