Solar91 Cleantech, Rays Power Experts, Stockwell Solar Services, Oriana Power, and Inox Renewable Solutions won NTPC Vidyut Vyapar Nigam’s (NVVN) auction to set up 500 MW/1,000 MWh standalone battery energy storage systems (BESS) in Rajasthan.

Solar91 won 50 MW at a tariff of ₹216,000 (~$2,490.20)/MW/month. Rays quoted a tariff of ₹218,700 (~$2,521.33) to secure 50 MW. Stockwell quoted ₹218,998 (~$2,524.76) and won 225 MW. Orinana secured 125 MW at ₹218,999 (~$2,524.78).

Inox won 50 MW of the quoted capacity of 125 MW at a tariff of ₹219,000 (~$2,524.79).

This is the lowest price ever for a BESS auction. The previous lowest tariff was ₹219,001 (~$2,525.94)/MW/month.

The tender was floated on February 28, 2025.

The winners will receive a viability gap funding (VGF) of ₹2.7 million (~$31,142.12)/MWh or 30% of the awarded project capacity’s capital cost, whichever is lower.

The project’s scope of work entails setting up the BESS and its interconnection with the state transmission utility network. It also includes constructing the substation bay.

Successful bidders must make the BESS available to NVVN for charging or discharging the storage system on an “on-demand” basis. They must also obtain all approvals, permits, and clearances for setting up the project and its dedicated transmission network up to the delivery point (including connectivity).

The Ministry of Power announced the second tranche of viability gap funding (VGF) to support BESS development. Under this tranche, a VGF of ₹1.8 million (~$21,043)/MWh will be provided to support the development of 30 GWh of BESS capacity.

Of the proposed 30 GWh, 25 GWh of storage capacity has been allocated across 15 states, while NTPC will develop the remaining 5 GWh.

According to the CEA, a 37 GWh BESS capacity is required by 2027, and this requirement is expected to increase to 236 GWh by 2031-2032. A BESS capacity of 13.2 GWh has been approved under the ongoing VGF program for BESS development.

In March 2025, the Ministry directed all states and implementing agencies to award all BESS contracts by June 2025, enabling the VGF program to be completed by May 2027.