Hydro power projects are classified as large and small hydro projects based on their sizes. Different countries have different size criteria to classify small hydro power projects. In India, hydro power plants with capacity of 25 MW or below are classified as small hydro. Hydro Power was looked after by Ministry of Power prior to 1989. In 1989, plant capacity up to 3MW and below was transferred to the Ministry of New and Renewable Energy (MNRE). Thereafter, many initiatives were taken by this Ministry since then for the promotion of small hydro which included implementation of a UNDP-GEF assisted Technical Assistance project entitled “Optimizing Development of Small Hydro Resources in Hilly Regions of India” and India-Renewable Resources Development Project with IDA credit line having interalia small hydro development component with target of 100MW canal based small hydro power projects through private sector participation. Subsequently plant capacity up to 25MW and below was entrusted with the MNRE in November 1999.
The estimated potential of 21133 MW from 7133 sites for power generation in the country from small / mini hydel projects was assessed by Hydro and Renewable Energy Department (HRED), earlier known as Alternate Hydro Energy Centre (AHEC) of IIT Roorkee in its Small Hydro Database of July 2016. The hilly States of India mainly Arunachal Pradesh, Himachal Pradesh, Jammu & Kashmir and Uttarakhand, and constitute around half of this potential. Other potential States are Maharashtra, Chhattisgarh, Karnataka and Kerala. Focused attention is given towards these States through close interaction, monitoring of projects and reviewing policy environment to attract private sector investments.The statewise location of identified SHP sites are given - Andhra Pradesh , Arunachal Pradesh , Assam , Bihar ,Chhattisgarh , Goa , Gujarat , Haryana , Himachal Pradesh , Jammu & Kashmir , Jharkhand , Karnataka , Kerala , Madhya Pradesh , Maharashtra , Manipur ,Meghalaya , Mizoram , Nagaland , Orissa , Punjab , Rajasthan , Sikkim , Tamil Nadu , Tripura , Uttar Pradesh , Uttarakhand , West Bengal