Hydrogen can be used as a fuel for cars and other vehicles, either in a conventional internal combustion engine or as fuel cells. Hydrogen contains chemical energy that can be released by burning hydrogen fuel or through the reaction of hydrogen and oxygen in a fuel cell. Hydrogen fuel cells are currently expensive to produce and easy to break. They are also difficult to use in cold conditions. Hybrid vehicles can be powered by a combination of hydrogen fuel cells and conventional gasoline.
Hydrogen fuel is not a naturally occurring substance. It must be produced artificially. This means that hydrogen is considered to be a carrier of energy, rather than a source. Energy is taken from a source, which might be a conventional power plant, a renewable energy source or nuclear power, and used to produce hydrogen. The hydrogen acts as a store or carrier for the energy until it can be used, in order to run a car, or for some other purpose. Approximately 35 million tons of hydrogen are currently produced every year, worldwide, for use in industry.
Hydrogen can be produced from fossil fuels, ethanol or methane, but it can also be derived from water. There are a number of integrated wind to hydrogen power plants, for example that use wind turbines to generate the power needed to create hydrogen fuel through the electrolysis or splitting of water. When hydrogen is produced in this way, or through a similar system that does not rely on fossil fuels, it is a clean form of energy. No carbon dioxide is produced, and when the hydrogen fuel is used in a car, it does not create any harmful pollution. Hydrogen fuel cells use hydrogen and oxygen, and create electricity and water. When hydrogen is burnt in a combustion engine, the waste products are heat and water.
However, there are some disadvantages to using hydrogen as a car fuel, many of which relate to the difficulties in transporting and storing liquid or gaseous hydrogen and the necessity of constructing the infrastructure to handle hydrogen fuel and make it available for drivers. Hydrogen contains less energy, relative to its volume than gasoline. This means that more hydrogen is needed in order to obtain the same amount of energy, which causes a problem with storage since vehicles need to carry more fuel if they are running on hydrogen.
The production of hydrogen fuel for cars is another problematic area since the production method determines whether or not the fuel can be considered clean and environmentally friendly. The current methods of production also tend to be too inefficient.
There is a lot of excitement about the potential for increased use of hydrogen in the future, as the technology for producing and using hydrogen fuel in cars is developed and improved. Hydrogen could potentially replace fossil fuels, removing dependence on imported oil and helping to promote a greener, cleaner future. However, in order for hydrogen to become a practical alternative to gasoline, its efficiency and production methods need to be improved.
Some hybrid and hydrogen fueled cars are already available, but there are only a limited number of places where these cars can be refueled. California has the greatest concentration of cars powered by hydrogen fuel cells, although there are only about 65 cars, supported by 26 refueling stations, in the state.
Hydrogen fuel can be used for other purposes as well as to power cars. It can be used to store the energy produced by intermittent sources of renewable energy, such as solar and wind power, for example. PennEnergy.org is an informative website where it is possible to learn more about alternative car fuels and other types of renewable energy.