By Rajesh Kaushal, Business Group Head, Energy Infrastructure & Industrial Solutions – India and SAARC, Delta Electronics India
India has proven that it can build renewable capacity at remarkable speed. The next test is whether it can deliver that power reliably – on demand, not just on schedule. Battery energy storage systems (BESSs) are how India will close that gap. Solar generation peaks during the day, wind generation varies with weather conditions, while electricity demand follows a very different curve. As renewable penetration increases, the gap between generation and demand becomes more complex to manage. BESS can help bridge this gap by storing electricity when it is available and delivering it when required, while also supporting grid stability, peak management and better utilisation of renewable energy.
Growing opportunities for BESS
The scale of India’s requirement makes the direction clear. The Central Electricity Authority’s National Electricity Plan projects approximately 47.24 GW/236.22 GWh of BESS requirement by 2031-32, as part of the country’s overall storage requirement. Policy support is also accelerating deployment. Under the government’s first viability gap funding (VGF) programme, 13.22 GWh of BESS capacity is under implementation with a budgetary allocation of Rs 37.6 billion. Another VGF scheme, with an allocation of Rs 54 billion, supports 30 GWh of BESS capacity, reflecting the increasing importance of storage in India’s power system.
The opportunity extends beyond utility-scale renewable integration. For commercial and industrial consumers, BESS can support peak shaving, renewable energy optimisation, demand management and continuity of critical operations. Data centres, manufacturing facilities, commercial infrastructure, railways and microgrids increasingly require energy systems that can respond dynamically to changing grid and load conditions.
The shift towards railway applications is already visible on the ground. In February 2026, the Kolkata metro inaugurated a 6.4 MWh/4 MW BESS at the central substation of its Blue Line, implemented by Delta Electronics India – making it the first underground metro railway in India to install a large-scale BESS.
The next challenge is integration
As BESS deployment scales, success will not depend on battery capacity alone. A reliable storage system requires batteries, a power conversion system (PCS), a battery management system, an energy management system (EMS), protection architecture and a grid interface to operate as one coordinated system. The PCS is particularly important because it sits at the interface between batteries and the electrical network. It must manage bidirectional power flow efficiently while responding rapidly to changing grid conditions. The EMS adds another layer of intelligence by determining when energy should be stored, despatched or retained based on load, renewable generation and operating priorities.
This integrated approach will become increasingly important as applications move towards renewable firming, peak management, microgrids, grid support and more advanced grid-forming capabilities.
Building the intelligence behind energy storage
BESS is an integral part of the broader transformation towards intelligent and resilient energy infrastructure. Thus, at Delta Electronics India, our approach goes beyond individual components – it is about how PCS, EMS, power electronics expertise and system integration capabilities come together to enable storage solutions across utility, and commercial and industrial applications. This is embodied in Delta’s Integrated Battery Storage Solution – a complete 5MWh BESS that brings together batteries, PCS, EMS and BMS within a single, seamlessly integrated system.
Importantly, India’s BESS expansion also creates an opportunity to strengthen domestic engineering and manufacturing capabilities. Delta has been supplying PCS solutions for BESS applications in India since 2018 and has developed local manufacturing capabilities for PCS. Building such capabilities within India strengthens supply chain resilience while creating engineering expertise aligned with local grid and operating conditions. The next phase of India’s energy transition will not be defined only by how much renewable capacity we install. It will be defined by how intelligently we manage that energy. As renewable penetration rises and electricity becomes increasingly central to industrial and economic growth, storage will evolve from being a supporting technology to becoming a fundamental part of India’s power infrastructure. BESS will emerge as one of the key technologies turning renewable capacity into reliable, despatchable and intelligent power.
