A hydrogen vehicle is a vehicle that uses hydrogen as its on-board fuel for motive power. The term may refer to a personal transportation vehicle, such as an automobile, or any other vehicle that uses hydrogen in a similar fashion, such as an aircraft. The power plants of such vehicles convert the chemical energy of hydrogen to mechanical energy (torque) in one of two methods: combustion, or electrochemical conversion in a fuel-cell:

• In hydrogen internal combustion engine vehicles, the hydrogen is combusted in engines in fundamentally the same method as traditional internal combustion engine vehicles.
• In fuel-cell conversion, the hydrogen is reacted with oxygen to produce water and electricity, the latter of which is used to power an electric traction motor.

Buses, trains, PHB bicycle, cargo bikes, golf carts, motorcycles, wheelchairs, ships, airplanes, submarines, high-speed cars, and rockets already can run on hydrogen, in various forms and sometimes at great expense. NASA uses hydrogen to launch Space Shuttles into space. There is even a working toy model car that runs on solar power, using a regenerative fuel cell to store energy in the form of hydrogen and oxygen gas. It can then convert the fuel back into water to release the solar energy.

The current land speed record for a hydrogen-powered vehicle is 333.38 km/h (207.2 mph) set by a prototype Ford Fusion Hydrogen 999 Fuel Cell Race Car at Bonneville Salt Flats in Wendover, Utah on August 2007. It was accompanied by a large compressed oxygen tank to increase power.

The hydrogen economy is a proposed method of deriving the energy needed for motive power (cars, boats, airplanes), buildings or portable electronics, by reacting hydrogen (H2) with oxygen, the hydrogen having been generated by a number of possible methods, including the electrolysis of water. If the energy used to split the water were obtained from renewable power sources, and not from burning carbon-based fossil fuels or nuclear power sources, a hydrogen economy would greatly reduce the emission of carbon dioxide and therefore play a major role in tackling global warming. Countries without oil, but with renewable energy resources, could use a combination of renewable energy and hydrogen instead of fuels derived from petroleum, which are becoming scarcer, to achieve energy independence.

Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License)

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