Advantages and Disadvantages of MHD System

Advantages and Disadvantages of MHD System

Advantages of MHD System :

1. It converts heat energy directly into electrical energy at higher conversion efficiency compared to convectional type of power plants.
2. These systems are reliable and produces power pollution free.
3. Large amount of power is generated with small sized plants as compared to conventional power plants . It reaches to almost full power as soon as it is started.
4. The capital cost is comparable to conventional power plants. Thus the cost of power generation per unit is less.
5. The operational and maintenance costs are low.
6. The efficiency of MHD plants is 50% as compared to maximum of 40% of the most efficient conventional power plants It can work on any type of fuel.

Disadvantages of MHD System :

1. It has high fluid friction losses and heat transfer losses.
2. MHD generators operate at very high temperatures to obtain ionisation of gases and to make it electrically conductive. But the electrodes must be relatively at lower temperature.
3. It increases the resistance of gases in vicinity of electrodes since the gases in vicinity of electrodes are comparatively colder.
4. It causes large voltage drop across the gas film.
5. It needs large sized magnets which increases the cost of MHD systems.