Hydrogen is one of the most abundant chemical substances on the earth. It is a highly combustible diatomic gas. Also, it is tasteless, odourless and colourless. The processing of energy materials uses a large amount of hydrogen. Hydrogen can act as a fuel for many applications. One such application is a fuel cell. Fuel cells harness the power of hydrogen to generate electricity.
FUEL CELLS
The concept of the fuel cell was first demonstrated by the British chemist, Humphry Davy in 1801. And the first fuel cell was invented by a physical scientist, William Robert Grove in 1839.
Fuel cells generate electricity by means of chemical reactions. It is a highly efficient energy conversion device. One of the major highlights of fuel cells is that they are pollution free. And also they do not produce any greenhouse gases. All these characteristics are because of the use of hydrogen as the fuel in the fuel cells.
WORKING OF FUEL CELL
A fuel cell has two electrodes, namely anode (positive) and cathode (negative). These electrodes are separated by an electrolytic medium. As told before hydrogen acts as the fuel for the fuel cell. For the generation of electricity, the chemical reaction between and air molecules should happen. The air is supplied to the cathode and the hydrogen is supplied to the anode. These hydrogen and air molecules reach the electrolytic medium and react together to generate the electricity and water.
Catalysts present in theses electrodes cause the hydrogen to oxidise and generate the hydrogen ions and electrons. The electrons thus generated pass from the anode to cathode through the external circuit shown in the figure. This flow of electrons generates a direct current at the circuit. The hydrogen ions reach the cathode through the electrolytic medium. These ions react with oxygen from the air molecules present at the cathode and thereby generating water and heat. Some unused gases are also produced along with the water.
APPLICATIONS
Fuel cells can easily be combined with other energy technologies such as solar and wind systems. And also they are highly efficient than ordinary combustion engines. Also, fuel cells are environment-friendly as they are pollution free. The main pitfall of hydrogen fuel cell technology is the high expense. Production and storage of this hydrogen fuel end up with a high cost.
WORKING OF FUEL CELL
A fuel cell has two electrodes, namely anode (positive) and cathode (negative). These electrodes are separated by an electrolytic medium. As told before hydrogen acts as the fuel for the fuel cell. For the generation of electricity, the chemical reaction between and air molecules should happen. The air is supplied to the cathode and the hydrogen is supplied to the anode. These hydrogen and air molecules reach the electrolytic medium and react together to generate the electricity and water.
 |
| Fig 1. FUEL CELL |
APPLICATIONS
- Can be used as a power source for residential and industrial purposes and also in remote locations such as spacecraft, remote weather locations, and in some defence applications.
- Used for powering some automobiles (Fuel cell vehicles)
- Used with waste water treatment plants.
- The waste heat generated from the fuel cells can be used for some energy efficient applications (Co-generation).
Fuel cells can easily be combined with other energy technologies such as solar and wind systems. And also they are highly efficient than ordinary combustion engines. Also, fuel cells are environment-friendly as they are pollution free. The main pitfall of hydrogen fuel cell technology is the high expense. Production and storage of this hydrogen fuel end up with a high cost.
