
The advantages of using hydroelectric as a source of energy to generate electricity are.
- It is a renewable energy.
 - Building a dam does not pollute the environment.
 - In a lot of country, water can be easily obtained and is free.
 - Building a hydroelectric plant does not involve very high technology as nuclear power plant.
 
The disadvantages of using hydroelectric as a source of energy are.
- Building a dam will cause a large area flooded with water, and hence seriously destroys the ecosystem nearby.
 - The flooded area causes the loss of wild life habitat and agriculture land.
 - Dam failure happens will cause a disaster to the lower reaches area of the river.
 - The cost to build a dam is very high.