ACME Solar Holdings and Ceigall India have won Rewa Ultra Mega Solar’s (RUMSL) auction to develop a 600 MW grid-connected, ground-mounted solar power project with a battery energy storage system (BESS) in the Morena Solar Park, Madhya Pradesh.

ACME and Ceigall won 220 MW each at a tariff of ₹2.76 (~$0.0313)/kWh and ₹2.7 (~$0.0306)/kWh, respectively.

The tariffs are the lowest ever for a firm and a dispatchable renewable energy (FDRE) project.

The tender was floated in September 2024.

Winners must develop, operate, and maintain two units each of up to 300 MW of grid-connected ground-mounted solar projects, with BESS, for the supply of 220 MW at any time block and supply of up to 440 MWh during the peak supply period.  The 9-hour peak supply period will be divided into a 4-hour morning peak and a 5-hour evening peak.

Madhya Pradesh Power Management Company (MPPMCL) will provide nighttime charging power for the BESS component of the units per the power purchase agreements. MPPMCL will procure power on behalf of the three distribution companies in Madhya Pradesh.

RUMSL will develop the evacuation infrastructure for the power offtake from the projects.

The project must ensure a minimum annual availability of the peak supply of up to 95%.

Winners will receive payments for excess power supplied beyond 220 MW and up to 300 MW at a tariff of ₹2.15 (~$0.024)/kWh.

The projects must ensure a minimum annual capacity utilization factor of 35%.

In December 2024. RUMSL awarded Waaree Group the auction to develop a 170 MW solar power project at the Neemuch Solar Park in Madhya Pradesh. The company quoted a tariff of ₹2.15(~$0.025)/kWh to win the auction.

In September this year, the MPPMCL invited bids to procure 500 MW of energy storage capacity from interstate transmission system-connected pumped storage projects. The project entails the supply of energy storage on a demand-based basis for 40 years, on a build, own, and operate basis.