(energy of water flowing in rivers).
-Another traditional source of energy was the kinetic energy of flowing water or the potential energy of water at a height.
-Hydro power plants convert the potential energy of falling water into electricity. Since there are very few water-falls which could be used as a source of potential energy, hydro power plants are associated with dams.
-In the last century, a large number of dams were built all over the world. A quarter of our energy requirement in India is met by hydro power plants.