Hydrogen and oxygen can combine to produce electric power in fuel cells. Such electric power can replace internal combustion engines for transport and other important everyday applications. This technology is limited by the difficulty in storing and transporting hydrogen. It has relatively low energy per unit volume, so one would need to carry huge quantities of gas around to drive a car for even a small distance.
Hydrogen can be cooled into a liquid state and is somewhat more energy efficient for volume in this state. However, there is no easy way to cool hydrogen and keep it in a liquid state at the individual consumer level. Fuel processors are used to liberating hydrogen from natural gases such as propane, methanol, ethanol, and natural gas that are denser than hydrogen itself. Fuel processors may also liberate hydrogen from a liquid fuel such as gasoline. This makes it more practical to use fuel cells.
A steam reformer is one kind of fuel processor.
Steam reformers work on either methanol or on natural gas. Liquid methanol and water are converted into gaseous states using heat and a catalyst. The methanol liberates hydrogen as it comes in contact with the catalyst. This process also liberates a noxious gas, carbon monoxide. Carbon monoxide is a pollutant. However, oxygen liberated from water vapor converts most of the carbon monoxide into carbon dioxide. This controls the pollution impact of a fuel processor. A fuel processor can liberate hydrogen from methane in natural gas. The carbon monoxide that is not oxidized can be burnt to reduce if not eliminate dangerous emission.
The volume of hydrogen generated by a fuel processor can be controlled by the rate of flow of methane or natural gas. This volume of hydrogen determines the amount of electricity generated, which in turn determines the amount of torque produced by an electric motor in combination with an inverter. This torque can be used for motion or any other application as in the case of other forms of energy. Voltage is produced as a direct current. A fuel cell may be fixed at one place to generate electric power or it may be designed to be transportable as for example, in the form of a power source for a vehicle.
Proton Exchange Membranes, Alkaline, Phosphoric acid, Solid oxide, and molten carbonate are other types of fuel cells. They all rely on hydrogen and oxygen to produce electricity. Fuel processors hold the key to overcoming the problems of storing large quantities of hydrogen gas and of keeping large volumes of hydrogen in liquid form.
Fuel processors produce some amounts of carbon dioxide, which may be a considered to be a pollutant for the ozone layer of the atmosphere. Fuel processors are also relatively inefficient in producing energy from fuel. Researchers are working on finding solutions to these drawbacks of fuel processors. However they remain a useful alternative to internal combustion of fossil fuels. Fuel cells can also replace batteries used to power electric devices and turbines that produce industrial amounts of power.Fuel processors