Question

"In spit of being cheaper ,pollution free and renewable sources of power,significance of hydroelectricity has declined".justify the statement by giving any four arguments.

Answer 1

Hydropower is fueled by water, so it's a clean fuel source, meaning it won't pollute the air like power plants that burn fossil fuels, such as coal or natural gas. Hydroelectric power is a domestic source of energy, allowing each state to produce their own energy without being reliant on international fuel sources.
hope it will help you.

Answer 2

1) hydroelectricity is cheaper because it is renewable sources that is rainfallt fills up the dam that helps in running turbine so extra cost is saved
2) like coal water is not required to be burnt and harmfull polluted air is not released in the air
the water is just made to flow from height that winds turbine hence electricity is produced
now although being good it is not useful because
1) rains may fail that may not fill water in rivers hence a huge crisis to produce electricity
2) a large amount of water should be stored to run turbines which is sometimes not possible due to evaporation..so turbines dont run
3) canals without dam are not at a height so water with full force do not come down to run the turbines
4) many places in india are there where plenty of rainfall do not take place so river bed remains dry and thus hydroelectric plant cannot be established