NTPC Green Energy (NGEL) has invited bids to develop 3,300 MWh of battery energy storage systems at NTPC Renewables’ (NTPC REL) solar project in Khavda, Gujarat.

The scope of work includes the design, engineering, supply, packing and forwarding, transportation, unloading, storage, installation, testing, and commissioning of the grid-connected battery storage system on a turnkey basis.

The scope also includes integration with solar plant balance-of-system infrastructure and the grid, civil works, bus extension works, auxiliary supply systems, engineering drawings, performance guarantee test procedures, site acceptance planning, training, and special tools and tackle required for maintenance.

The selected bidder must also provide comprehensive operation and maintenance services, including warranty support and an annual maintenance contract, for 15 years.

Bids must be submitted by June 25, 2026. Bids will be opened on the same day.

The project will be developed at the pooling substation (PSS)-1 of the NTPC REL’s Khavda solar park.

It comprises four storage blocks. Block-1, Block-2, and Block-3 will each have a capacity of 300 MW/900 MWh, while Block-4 will have a capacity of 200 MW/600 MWh.

Each block will be connected at the 33 kV level of a designated 300 MW solar project. The battery storage capacity will be considered as the rated alternating current discharge capacity at the point of injection at the interstate transmission system substation.

Bidders must account for the auxiliary consumption of the storage plant during discharge when determining the discharge capacity.

The system, including the battery, must have a design life of 25 years from the date of commissioning, based on daily single-cycle operation and degraded capacity as proposed by the bidder. The batteries must be rated for at least 10,000 operating cycles.

Bidders must guarantee at least 92% dispatchable capacity at the point of injection across the 15-year operating period. The system must provide 100% of the rated dispatchable capacity on the commercial operation date and 95% of the dispatchable capacity during the first year. The dispatchable capacity at handover must be at least 92%.

They must also conduct grid compliance studies for the designated solar, storage, and power-evacuation systems. Power quality compliance for the complete system up to the grid interconnection point at the interstate transmission system switchyard will also fall within the bidder’s scope.

The storage system must maintain a minimum monthly round-trip efficiency of 80%, including auxiliary consumption measured at the termination point or point of coupling. The annual availability must be maintained at 98%.

The energy management system must be configured to operate the battery storage system in various modes as required by the grid, support integrated operation with solar plants, and meet scheduling requirements during operation and maintenance.

Recently, NGEL invited bids to develop 7,800 MWh of battery energy storage systems at NTPC REL’s solar project in Bikaner.

Last month, NGEL declared the commercial operation of 105 MW of solar capacity at the 1,200 MW Khavda II project in Gujarat.