Hydroelectricity is the third important source of energy in the country after coal and petroleum. It is the main source of energy in Arunachal Pradesh, Himachal Pradesh, Jammu and Kashmir, Kerala, Meghalaya and Sikkim fulfilling over 90 per cent of their power need. Other states like Haryana, Karnataka, Orissa, Punjab and Rajasthan meet more than 50pet cent of their energy requirement through hydro- electricity.
Hydro-electricity is a renewable energy resource, transportable to long distances and is fret from environmental pollution. It could be mad more viable by putting emphasis on mini power projects instead of going for giant multi-purpose projects which are fewer environments friendly. Hydroelectricity is a cheap source of energy which requires perennial rivers with sufficient flow water throughout the year and suitable sites for building dams and fixing turbines.