As India rapidly scales up renewable energy capacity, the power sector’s focus is increasingly centred on balancing capacity addition with system reliability. While achieving renewable energy targets remains essential, it is no longer sufficient on its own. The central challenge now is to ensure grid stability and round-the-clock power availability as the share of variable renewable energy in the grid continues to rise.
The Central Electricity Authority’s (CEA) resource adequacy studies underline the critical role of long-duration energy storage in enabling large-scale renewable integration beyond 2030. On an all-India basis, storage capacity requirements are projected to increase sharply– from about 62 GW by 2029-30 to 161 GW by 2034-35, and further to nearly 476 GW by 2046-47 – clearly indicating the scale at which storage solutions will need to be deployed.
In this context, pumped storage projects (PSPs) have emerged as a strategic asset for the country’s power system. Against earlier estimates of around 100 GW, India has now been assessed to have nearly 270 GW of pumped storage hydro potential, significantly expanding the long-term opportunity for grid-scale storage deployment.
Policy and regulatory interventions are also being aligned to accelerate PSP execution. Notably, closed-loop, off-stream projects with no direct linkage to rivers have been categorised separately, requiring significantly fewer environmental and statutory clearances. Encouragingly, PSP development timelines have begun to compress, with several projects now being commissioned in nearly four years.
From a techno-economic perspective, PSPs also offer a competitive advantage over battery energy storage systems (BESS) for long-duration applications. While recent BESS auctions have discovered low tariffs, these have largely been for two-hour storage configurations. As storage duration requirements increase, costs are expected to rise, making PSPs increasingly cost-effective, particularly for durations of six hours and beyond.
Recognising the pivotal role of pumped storage in India’s evolving power system, the CEA has released a comprehensive roadmap outlining a pathway to achieving 100 GW of PSP capacity by 2035-36. The roadmap estimates an investment requirement of Rs 5.8 trillion in the segment to achieve the target.
Power Line’s Special Section on Hydro power in India examines key trends and developments in the hydropower segment, the emerging role of pumped storage projects, the future outlook for the sector and the way forward.