Advantages and Disadvantages of Dams are as follows:
Dams are used for storing water. This stored water is led down through large pipes or tunnels to lower levels. In the course of the fall of water, the water rotates turbines.
The produced mechanical energy is converted to electricity by the generators connected to it.
Transformers change the alternating current produced by the generators into current of very high voltage for easy transmission through long distances
Advantages of Dams:
(a) Economical: The cost of operating a hydroelectric plant is nearly immune to increases in the cost of fossil fuels. Operating labour cost is also low.
(b) Safe: Hydroelectricity produces the least amount of greenhouse gases.
Disadvantages of dams:
(a) Failure Hazard:
In the case of failure of dams, millions of people become homeless, sick and even die.
(b) Limited Service Life:
As rivers convey silt higher the siltation, lower will be the service life of dam.
(c) Environmental Damage:
Dams are responsible for habitat fragmentation, aquatic ecosystem disruption, and greenhouse gas emissions.
(d) Population Relocation Problem:
Millions of people need relocation and generally they do not get necessary compensation.
(e) Energy Production is affected by amount of river flow:
Especially during drought period, hydroelectric power cannot be generated.