Power Grid Corporation of India (POWERGRID) has invited bids to select a pre-bid partner to set up standalone 250 MW/500 MWh battery energy storage systems (BESS) in Kerala.

The last date to submit bids is December 19, 2025. Bids will be opened on the same day.

This tender is a pre-bid tie-up, and its award is contingent on POWERGRID winning the upstream tender floated by NTPC Vidyut Vyapar Nigam.

POWERGRID must set up the BESS installation at the 220 kV Brahmapuram substation in Kochi, with an interconnection at the 220 kV voltage level within the jurisdiction of Kerala State Electricity Board.

The successful bidders must complete the project within 15 months. They must also undertake comprehensive maintenance of the project for 16 years.

The project’s scope covers the setup of the BESS, the power conversion system (PCS), and PCS transformers.

The BESS project must be designed for 2 hours of operation and single-cycle charging/discharging. It must also be designed to allow occasional dual-cycle per-day operation, with annual limits of up to 400 cycles on an on-demand basis.

Successful bidders can meet the technical criteria through two routes:

Route 1

Bidders must have been prime contractors who have supplied, erected, tested, and commissioned BESS projects of a cumulative capacity of at least 10 MWh. The projects must have been completed within the last seven years and operational as of December 19, 2025.

Alternatively, they can be prime contractors who have supplied, erected, tested, and commissioned at least one solar/wind project of at least 50 MW. The projects must have been completed within the last seven years and be operational as of December 19, 2025.

Prime contractors who have erected, tested, and commissioned at least two AIS circuit breaker-equipped bays of at least 132 kV in a single substation or switchyard are also eligible to bid. The projects must have been completed within the last seven years and operational as of December 19, 2025.

Route 2

Bidders could also be battery manufacturers who have supplied at least 50 MWh of batteries for stationary grid applications in the last three years.

They must also have a positive net worth in the last three years.

Additionally, bidders must have an average turnover of at least 6.08 billion (~$66.87 million) over the last five financial years.

They must also have liquid assets or evidence of access to or availability of credit facilities of at least ₹1.01 billion (~$11.1 million).

Startups and MSEs meeting 80% of the minimum average annual turnover liquid assets criteria will also be eligible to bid.

In November 2025, POWERGRID invited bids to select a consortium partner to set up 1,000 MW/2,000 MWh of standalone BESS across seven substations in Andhra Pradesh.