Tamil Nadu Green Energy Corporation Limited (TNGECL) has sought approval from the Union government for additional funding of Rs 1.8 million per MW for its battery energy storage system projects. The Ministry of Power has already cleared the setting up of BESS units with a total capacity of 2,500 MW.

According to TNGECL Managing Director Aneesh Shekhar, 1,000 MWh of battery storage capacity has already been allocated under the programme, delivering annual savings of around Rs 900 million. The corporation is currently in the process of finalising bids for the remaining 1,500 MWh of storage capacity to be implemented under the ministry’s viability gap funding framework.

In addition, TNGECL is planning to add another 1,000 MW of battery storage capacity, citing Tamil Nadu’s strong renewable energy potential. The state currently has an installed power capacity of 44 GW, with renewables accounting for about 55 per cent of the energy mix. Studies indicate that Tamil Nadu will require nearly 13 GW of energy storage capacity by 2035 to manage variability and ensure grid stability.

Shekhar said the expansion is necessary due to the steady rise in solar and wind generation. During non-peak hours, a significant portion of renewable power remains unutilised as the grid is unable to absorb the surplus. Large-scale battery storage would allow excess green power to be stored and supplied during evening and night-time peak demand periods.

Highlighting the role of Renewable Purchase Obligations, a senior TNGECL official said procurement of power from wind, solar, hybrid and round-the-clock renewable sources must follow tariff-based competitive bidding guidelines issued by the Ministry of Power.

With increasing renewable capacity being added to the grid, thermal power plants are being required to ramp generation up and down more frequently, placing stress on grid operations. Energy storage systems, the official said, will be critical in balancing supply and demand, storing surplus renewable power and ensuring smoother integration of clean energy into the grid.