Hydrogen has the maximum energy content per unit of weight amongst all other fuels. Domestic resources like coal, natural gas, biomass and water can be used to produce this gas. The good thing about it is that if hydrogen is burned in an engine, it has almost zero emissions.
For motors, hydrogen fuel can be used, as solar or nuclear energy are not viable options. Gasoline can be replaced by this gas as a fuel in an internal combustion engine. It produces thrice the energy as compared with gasoline.
However, as its density is one-tenth in liquid form and lesser in gaseous form, the fuel tanks have to be big. Also, they have to be insulated, and this makes them even bulkier. Liquid hydrogen can freeze air and cause accidents in plugged valves. As it is impossible to make a perfect insulation, the gas will evaporate at a rate of 1.7 percent per day.
Hydrogen Fuel Cell
Fuels like hydrogen, alcohol, methane or gasoline are converted to electricity directly in the cell. Pure water is the only byproduct and there is no other pollution. Such fuel cells are used wherever a clean and efficient power source is needed. These fuel cells can be readied to generate electricity in just 10 minutes.
The following equipment is essential.
- A glass of water
- A popsicle stick or similar small piece of wood or plastic
- A 9 volt battery clip
- 1' pure platinum or platinum coated nickel wire
- A 9 volt battery
- A volt meter
- Transparent sticky tape
The platinum wire is cut into pieces, each 6 inches long. Each piece is shaped as a tiny coiled spring on a nail, ice pick or a coat hanger. These act as the electrodes in the fuel cell.
The leads of the battery clip are cut to half and the insulation is stripped at the ends. Then, the bare battery lead wires are twisted to the ends of the platinum coated electrodes.
Further, a red and a black wire are connected to the electrodes, that are then connected to a volt meter. The electrodes are taped to the popsicle stick. This stick is taped to a glass of water. The electrodes have to be dipped in water entirely, while the connections have to be out of it.
The red wire must be connected to the positive terminal and the black wire to the negative terminal of the volt meter. The reading must be from 0 to 0.01 volts. The fuel cell is now ready. A 9 volt battery is connected for one or two seconds to the battery clip. Due to this touch, the water at the electrodes splits into hydrogen and oxygen by electrolysis.
While the battery is connected, bubbles can be seen at the electrodes. After the battery is removed, platinum works as a catalyst. The electrolysis reaction is reversed. The gases recombine to generate electricity.
If the electrode of any other material is used, the volt meter would read zero again. However, the platinum electrode shows just over 2 volts. As the reaction progresses, the voltage recedes. In this case, the energy from a 9 volt battery is stored as hydrogen and oxygen bubbles.
Any other energy source can be used. For example, solar power can be used during the day, the gases can be stored and used in the fuel cell at night. Or, they can be stored in high pressure tanks in an electric car to create electricity the car needs.
Any vehicle that uses hydrogen as an on-board fuel for motive power is called a hydrogen vehicle. It could be an automobile or an aircraft.
The chemical energy of this gas is converted into mechanical energy by electrochemical conversion in a fuel-cell. This conversion comprises reacting hydrogen with oxygen to generate electricity and water to power an electric traction motor. This technology has paved the way for cars powered by hydrogen fuel cells.
Hydrogen is not an energy source. Instead it is an energy carrier. This technology has the advantage of reduced emissions of greenhouse gases and ozone precursors. However, there are technical as well as economical challenges for the use of vehicles powered by this technology.