38-Role of Snow and Glacier Melt Runoff Modelling in Hydropower Projects in the Himalayan Region.

Abstract

At present the installed capacity of Indian hydropower projects is about 35900 MW, which represents 25% of the total installed capacity of India (1,43,000 MW). The share of hydropower generated in the Himalayan region is about 80% of the total hydropower generated in India. The huge hydropower potential in the Himalayan region is due to the availability of water and appropriate head in the Himalayan basins. The Government of India is seriously concerned with accelerating the pace of hydropower development to accomplish exploitation of the balance of the hydropower installable capacity (about 1,00,000 MW) in a reasonable time frame. The runoff generated from the melting of snow and glaciers plays a vital role on the perennial rivers of the Himalayas and ensures the continuous availability of streamfiow for hydropower projects. Rainfall contribution during the monsoon period is critical for storages in various reservoirs. The snow and glacier melt runoff is considered as highly dependable flow and used for irrigation, drinking water and generating hydropower particularly during summer period, when demand is at peak for power and irrigation. This paper presents the estimated contribution of snow and glaciers in the Himalayan rivers. It has been demonstrated that glaciers act as natural frozen reservoirs in the upper part of the basin and provide flows in a regulated manner for the operation of base load and peaking hydropower projects. This paper describes a modelling approach for snow and glacier fed basins and demonstrates its various applications for hydropower projects in Himalayan catchments including planning, design, operation and management of projects.