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Some hydrogen cars currently exist, but a significant amount of research has to be undertaken to make the technology viable. The common internal combustion engine, usually fueled with gasoline (petrol) or diesel liquids, can be converted to run on the gaseous hydrogen. However, the most efficient use of hydrogen involves the use of fuel cells and electric motors instead of a traditional engine. Hydrogen would react with oxygenOxygen is the chemical element in the periodic table that has the symbol O and atomic number 8. The element is very common, found not only on Earth but throughout the universe. Molecular oxygen (O, often called free oxygen on Earth is thermodynamically un inside the fuel cells, which would produce electricityElectricity is a property of certain subatomic particles, such as electrons and protons, that gives rise to attractive and repulsive forces between them. It is one of the four fundamental forces of nature, and is a conserved property of matter that can be to power the motors.
High speed cars, busThis article is about the form of transport. See computer bus or electrical bus for the use of the term in computing and electronics respectively, or places like Bus, Pas-de-Calais and Bus-Saint-Remy. The Bus, established by Mayor Frank Fasi, is Honolulu'es, submarineUSS Los Angeles (SSN-688)|USS Los Angeles A submarine is a specialized boat that travels under water, usually for military or scientific purposes. Most major navies of the world employ submarines. Submarines are also used for marine and freshwater sciences, and space rocketFor rocket lettuce, see arugula; for the early steam locomotive, see Stephenson's Rocket, for the sugar candy, see Rockets. A rocket is a vehicle, missile or aircraft which obtains thrust by the reaction to the ejection of a fast moving exhaust from withis already run on hydrogen, in various forms. The Fuel Cell Car Kit is a working toy model car that runs on solar power, using a reversible 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. They are available online [1].
Three major obstacles exist in the development of a fuel cell-powered hydrogen car. The first problem is that hydrogen has a very low densityFor other meanings of density, see density (disambiguation Density (symbol: rho Greek: rho) is a measure of mass per unit of volume. The higher an object's density, the higher its mass per volume. The average density of an object equals its total mass div. Even when the fuel is stored as a liquid in a cryogenic tank or in a pressurized tank as a gas, hydrogen cars have limited range compared to their conventional counterparts. Some research has been done into using special crystalThis article is about the form of solid matter. For other uses of this word, see Crystal (disambiguation . Insulin Crystals A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extendline materials to store hydrogen at greater densities and with better safety margins.
Instead of storing molecular hydrogen on-board, some have advocated using hydrogen reformers to extract the hydrogen from more traditional fuels including methane, gasoline, and ethanol. Many environmentalists are irked by this idea, as it promotes continued dependence on fossil fuels (at least in the case of gasoline). However, given an efficient reforming process, a vehicle using reformed gasoline or ethanol to power fuel cells would still be more efficient than vehicles running internal combustion engines.
The second major problem involves the fuel cells that would provide electric power in a hydrogen car. Scientists are also working hard to figure out how to produce inexpensive fuel cells that are also robust enough to survive the bumps and vibrations that all automobiles have to handle. Most fuel cell designs are fragile and can't survive in such environments. Also, many designs require rare substances such as platinum in order to work properly.
The third problem is that while hydrogen can be used as an energy carrier, it is not an energy source. It must be produced from fossil fuels, or from some other energy source. Since all energy sources have drawbacks, a shift into hydrogen powered vehicles will require difficult political decisions on how to produce this energy.
An existing conventional car cannot easily be converted to run from hydrogen, due to a number of inherent differences in the technologies. Other renewable energy sources, like biodiesel, are more practical for existing automobile conversions.
Despite these problems, United States President George W. Bush is optimistic that these problems could be overcome with research. In his State of the Union address, he announced the U.S. government's hydrogen fuel initiative which complements the President's existing FreedomCAR initiative, for safe and cheap hydrogen fuel cell vehicles.