How are these cars operated also how can I tell if it is hydrogen operated in terms of design and how to fill up?
A regular gasoline will not be benefited by using hydrogen. The engine has to be designed and the computer has to be tuned for it. Hydrogen that cars run from comes from water. Since water is 2 parts hydrogen and 1 part oxygen, a process called electrolysis extracts the hydrogen from the water.
the most efficient way to use hydrogen as fuel in an automobile is to use a hydrogen fuel cell the hydrogen and oxygen are passed through a cell where there is a PEM (proton exchange membrane) the hydrogen loses an electron and combines with the oxygen to produce water. The electron travels down a wire to drive an electric motor, charge a capacitor or charge an electric battery. The car is essentially an electric car beyond this point. The real expense comes with the PEM; Currently the only catalyst effective in hydrogen fuel cells is Platinum. As you can imagine even a thin layer of platinum on the multiple membranes required to make a fuel cell big enough to power an automobile add up to a BIG chunk of change. The cheapest way is to just burn it like you would gasoline. Hydrogen is flammable, so you can burn it in much the same way you would burn gasoline, the biggest pitfall here is storage, and the fact that you will still have carbon monoxide, carbon dioxide and other exhaust gasses that you have now. Another major pitfall for hydrogen vehicles is storage, and refill of hydrogen. Since it is a compressed gas, you cannot just drop a spout in and refill a container like you can with a liquid fuel. The gas would atomize and evaporate way too fast.
