MUMBAI - Tata Power has operationalized 60 megawatt-hours (MWh) of battery energy storage systems (BESS) across three strategic locations in Mumbai, taking a concrete step toward strengthening the city's distribution grid and managing evening peak demand more efficiently.
The battery energy storage system (BESS) devices are functioning in the areas of Mahalaxmi, Saki, and Mankhurd to serve the distribution network that accommodates about 800000 users in Mumbai. This is the beginning of the entire activity according to the approved design, which foresees the expansion of the BESS system in the city at the rate of 200 MWh at 10 locations and its approval by the Maharashtra Electricity Regulatory Commission in April 2025.
The core idea behind this installation is the energy arbitrage. The BESS units will store energy when solar energy is cheap during the daytime, and give it back to the grid at night, namely during the peak consumption period with the highest costs of electricity.
BESS units have fast response and high ramp-rate capabilities, which enable the distribution system to respond to changes in demand dynamics and to manage loads dynamically. The systems operate at about 1 to 1.5 cycles per day, i.e., the operating mode is more suitable for daily peak shaving rather than long-term energy. Their grid-connected and decentralized concepts improve storage and dispatch at a local level, while the function of black start allows for the introduction of restoration functions in the event of any disturbances in the power system operation.
The deployments build on Tata Power's broader infrastructure push in Mumbai. The company has committed approximately ₹300 crore to BESS as part of a wider plan to deploy 100 MW/200 MWh of battery storage across generation, grid-level and consumer-end applications. Nilesh Kane, Chief of Transmission and Mumbai Distribution at Tata Power, has said the initiative is aimed at enhancing grid reliability, improving demand-side flexibility and optimizing power procurement costs. The storage systems are also positioned to support three demand drivers in the Mumbai Metropolitan Region: the expansion of data centres requiring high-reliability connections, the growing Metro rail network, and large-scale urban redevelopment driving high-rise residential load.
The rollout of the bigger 200 MWh BESS aims to enhance grid reliability, improve reactive power management, and ensure quick restoration of power supply to places requiring uninterrupted energy such as hospitals, metro services, airports, and data centres. Tata Power's network for the distribution of electrical power in Mumbai covers around 5,911 km and should exceed the 900,000 consumer figure in the near future, and the company is planning to increase the number of its substations from 37 to 50.
Tata Power is one of the companies owned by Tata Group and has an overall operational and under-construction capacity exceeding 26 GW, which includes around 17.7 GW of clean energy and about 8.8 GW of thermal power. Its transmission and distribution network includes over 7,800 kilometers of circuits and serves more than 13 million clients throughout its distribution operations.
The Mumbai BESS deployment adds a distributed storage layer to that portfolio. As peak loads rise and renewable penetration deepens, the utility is betting that localized battery storage can make the city's electricity network more flexible, reduce costly peak-hour purchases and provide backup support for critical infrastructure. The project also offers a template for urban utilities seeking to combine storage with existing distribution assets rather than relying solely on traditional grid upgrades.
