NLC India has announced the winner of its auction to set up a 250 MW/500 MWh battery energy storage system (BESS) at the Tamil Nadu Transmission Corporation’s substations.

Pace Digitek won the auction for the engineering, procurement, and construction (EPC) of BESS for the Ottapidaram, Annupankulam, and Kayathar substations at a tariff of ₹7.10 billion (~$73.62 million).

The tender was floated in January this year.

NLC India Renewables had won the 250 MW/500 MWh BESS capacity at a tariff of ₹248,000 (~$2,575)/MW/month in Tamil Nadu Green Energy Corporation’s auction, which was concluded in the same month.

The scope of work entails the design, engineering, manufacturing, erection, testing, and commissioning of the BESS project. It also includes providing operation and maintenance (O&M) services for 12 years.

The BESS must have a minimum round-trip efficiency of 87% for its first operational year and 85% from the second to the 12th year. It must demonstrate a system availability of 95%.

Pace Digitek must undertake the project’s civil works. This includes providing free issue items, services, and performance demonstrations, along with associated equipment and materials, on a turnkey basis.

It must pay the registration and statutory inspection fees related to its scope of work. It must also provide all equipment and materials required to implement reactive power compensation systems and harmonic filters.

Pace Digitek must reroute existing utility transmission lines, undertake area grading and filling, and construct the approach road to the project’s lease land, wherever required.

It must obtain approvals, permits, and clearances from local administrative or statutory bodies for the project. These include environmental clearances, land-use permits for the project and its transmission system, access, and water for construction and O&M activities.

The company must also obtain approval from the Central Electricity Authority or other statutory authorities before charging the BESS.

The scope of work also includes a 12-year warranty for the BESS project’s works and equipment, including a five-year warranty for the power conversion system.