Which of the following statements about hydroelectric power is true?

1.Hydroelectric power harnesses the energy of water moving downhill in streams

2 hydroelectric power is a renewable energy resource

3 hydroelectric dams can be placed on any stream, regardless of location

4 Dams used for hydroelectric power generation can typically last for many centuries

5.Hydroelectric dams often result in significant ecological damage

Answer:

The correct options are :-

• .Hydroelectric power harnesses the energy of water moving downhill in streams
• Hydroelectric dams often result in significant ecological damage
• hydroelectric power is a renewable energy resource

Step-by-step explanation

Hydroelectric power refers to the generation of electric power from the kinetic energy of running water. This can be generated in various ways such as :-

• By building a hydroelectric dam
• By pressure storage where water is pressurized onto the turbine
• Run of stream where the power is generated directly from the water running downstream in a stream.

Hydroelectric power is a renewable source of energy i.e it can be used again and again because they are naturally replenished.

The hydroelectric dams are placed at suitable places depending upon the geology and ecology of the area and thus cannot be placed anywhere in the stream.

Dams usually have an average age of 50 years i.e they function properly for 50 years or so. Thus they don't last for many centuries because of the corrosion and destruction of the metals and concrete used.

Building of a hydroelectric dam damages the ecology of the area as :-

• A huge area is required for the building of the dam which requires forest clearing, drilling, Quarrying etc which offsets the ecology
• Reservoir is created at the upstream side which results in limited flow of water in the downstream side thus affecting the ecology.
• Generation of hydroelectric power requires installation of huge turbines and machinaries which can create noise and thus affect the ecology.