Hydrogen as a fuel for cars

Hydrogen is one of the simplest elements in existence, containing only one proton, and is the most plentiful gas in the universe. It has the highest energy content of all any known fuel, but it does not physically exist on earth as a gas, and so must be extracted from other sources like water and natural gas. The two most successful methods for extracting hydrogen are steam reforming, in which hydrogen atoms are separated out from the fossil fuel methane (CH4), and electrolysis where an electrical current is passed through water (H20) to split the hydrogen from the oxygen.

In recent years hydrogen energy has been utilised for the automobile industry and fuel cells have been developed that store hydrogen (either in gas or liquid form) and then convert the energy from the hydrogen into electricity, which is used to run an electric motor to power the car. However these hydrogen fuel cells are not yet commercially viable as they are expensive to produce, and are not robust enough to stand against heavy use. Also the issue of where drivers would refuel is a problem, because the logistics of funding and building enough hydrogen fuel stations would be a huge obstacle. Manufacturers are currently trying to get around this problem by designing small hydrogen generators that could be installed into personal garages so that drivers could refuel their cars at home.

Another major problem with hydrogen cars currently is the environmental issues. You would expect a car running off an alternative power source to be better for the environment than regular fuel, but currently almost all of hydrogen produced commercially is obtained by processing fossil fuels, such as coal, oil and gas. Even though using hydrogen in your car would be emitting no harmful gases from your exhaust system, the process of obtaining the hydrogen in the first place could have already caused significant emissions. The only way around this is to develop more direct ways of obtaining hydrogen from the abundant source of water such as techniques such as electrolysis or heat disassociation. Heat disassociation can be powered by renewable sources such as solar or wind power, and hydrogen is extracted by heating water until it has formed steam, which is then forced through a spiral tube so that it undergoes a circular motion. This subjects the steam to a centrifugal force, which separates the hydrogen and oxygen molecules, and allows the hydrogen to be extracted for separate storage.