PUMPED STORAGE HYDROPOWER IN INDIA AND ITS INTEGRATION WITH RENEWABLE ENERGY

Abstract

Energy storage plays a vital role in security and stability of the power system. Energy storage systems are used to store the excess electricity generation during off-peak $ hours of the night. However, the introduction of renewable energy in the power system has renewed the need for energy storage as the generation from renewable sources poses multiple challenges to the power system due to its intermittent and variable nature. India has vast resources of renewable energy, having potential of almost 900 GW, and the study of renewable energy capacity addition trend indicates that by 2025-2030, India will be using very large quantity of renewable energy. Such high proportion of renewable energy generation needs large scale energy storage system to damp the intermittency and variability. Pumped Storage Hydropower (PSH) is the most reliable and proven large energy storage system. India is bestowed with large potential of PSH (96,524 MW) due to the mountainous terrain of the country. 1-lowever, out of this large PSI-I potential only 5% (4804 MW) potential is being utilized currently. The main reason for this under utilization of PSH potential has been the deficit of electricity in the country. As per Central Electricity Authority, in 2013-2014, all five electricity regions of the country experienced energy deficit totaling 4.2%. Layouts of potential PSH sites were drawn and elevation profiles were generated to calculate head, water-way and head ratio and slopes. It was observed that there is large variation between assessed and calculated head in most of the cases (107.5% being highest). In some instances, infeasible location of upper and lower reservoirs and technically impracticable long water-way distances (225 km in one case) were found and reported. In such discrepant cases alternate locations of reservoirs were studied and proposed. Further, the PSI-I layouts drawn were juxtaposed with transmission grid map, land use map and geology map to study the suitability of potential PSH sites for future development. Planning and design mechanisms were studied to explore the possibility of PSH development in discarded mine sites, existing/proposed dams etc. utilizing theses as reservoirs for PSH. Many states of India have abandoned mine sites e.g. Andhra Pradesh 1 HI has 15 such sites which should be explored for use as PSH reservoirs. A new concept called Gravity Power Module utilizing ground water was also reviewed. Planning of PSH development in India for renewable energy integration was also done by studying region wise and state wise power scenario and PSH potential available.