Introduction of Magneto Hydrodynamic (MHD) Power Plants

Introduction of Magneto Hydrodynamic (MHD) Power Plants 

1. Magneto hydrodynamic (MHD) is a device which converts the heat energy of a fuel directly into electrical energy without a conventional electric generator.
2. In a conventional thermal power plant the maximum temperature of the working fluid is restricted by the metallurgical properties of the turbine and other components like melting point of the turbine blade material etc.
3. The minimum temperature is limited due to the ambient conditions. Thus with the two temperatures limited, the maximum thermal efficiency of the system is limited.
4. To improve this direct conversion of heat into electricity by MHD-system is a good option. 
5. This will eliminate all the intermediate linking conversion processes thereby improving the efficiency.
6. Magneto Hydro Dynamic (MHD) is one such method which has undergone considerable development.
7. This method can make use of temperatures of the order of 2300°C to 2700°C as compared to the conventional steam power plants which can use maximum temperatures in the range of 750°C to 800°C only.
8. Thus the MHD generators are said to have high efficiency and low pollution.

Basic principle :

The working principle is based on Faraday's Law. It states that when a conductor is moved in a magnetic field an e.m.f. induced in the conductor. This conductor may be solid, liquid or gas. The directions of the magnetic field, the direction of motion and the e.m.f induced will be mutually perpendicular to each other. This is given by the Right Hand Rule as shown in Figure A.