India’s Solar‑Battery Auction Sets ₹5.25/kWh Benchmark

A groundbreaking solar‑plus‑battery auction organized by the Solar Energy Corporation of India has established a new cost reference for clean electricity. The 1,000 MW tender attracted sixteen participants, but only seven developers were awarded capacity, each submitting a bid within the tight range of ₹5.25 to ₹5.26 per kilowatt‑hour.

The auction design focused on delivering power when it is most needed—during evenings, nights and early mornings—while allowing lower supply levels during daylight when solar generation is plentiful. Sellers were obligated to provide at least 90 % of their contracted capacity during six peak hours chosen by the buyer, 70 % during other non‑solar periods, and 50‑60 % during solar‑rich hours. Performance is monitored in 15‑minute blocks, and any shortfall triggers a penalty equal to 1.5 times the contract price.

Using a decade of hourly weather data from ten Indian states, the study estimated that matching the reliability of a coal plant would require roughly three times the solar capacity (about 3 GW) and 12 GWh of battery storage for every 1,000 MW of contracted power in high‑solar regions like Rajasthan. States with less solar irradiance would need 15‑20 % more solar capacity, though storage needs stay similar.

Lead author Ummed Paliwal highlighted India’s favorable latitude, which limits seasonal fluctuations in solar output. The primary technical challenge is shifting surplus daytime solar energy into storage for consumption after sunset—a challenge that modern batteries are now able to meet at competitive costs.

Co‑author Nikhit Abhyankar noted that the narrow price spread reflects a significant drop in solar‑plus‑storage costs, signalling that ₹5.25/kWh is becoming the market‑driven price for dependable, low‑cost renewable power. This pricing model could influence long‑term planning for distribution utilities and provide a stable electricity supply for energy‑intensive sectors such as data centres, steel, aluminium and other manufacturing units.