According to experts at rating agency ICRA, more than 12 GW of capacity has been allocated in the country through hybrid and RTC (round-the-clock) renewable energy projects.

From 2018 to the present, approximately 12.8 GW of capacity has been awarded through hybrid and RTC channels. So far, the current fiscal year has witnessed RTC and hybrid tenders for around 4 GW of capacity. Railways' 960 MW project, Solar Energy Corporation of India Ltd's (1200 MW hybrid project), and RUVNL's (Rajasthan Urja Vikas Nigam Ltd) 600 MW and 1184 MW RTC projects are among the important projects. The share of renewable energy (RE)-based RTC projects is likely to increase in subsequent bids, as evidenced by SECI tenders released in the current fiscal year.

"We are currently seeing good traction in RTC projects, which is the right direction for the sector because it will address concerns about renewable energy's intermittent and variable nature." It is also critical in terms of grid stability over the long term. As a result, there is more emphasis on RTC tenders currently," said Girishkumar Kadam, Senior Vice President and Co-Group Head, Corporate Ratings, ICRA.

While RTC RE projects are gradually picking up, storage costs will be a major driver of RTC initiatives in the future. The capital cost of storage systems has risen recently. Currently, the capital cost for RTC projects with pumped storage is Rs.6.5-7 crore per MW, whereas the capital cost for RTC projects with battery energy storage systems is Rs.12-13 crore per MW. "In terms of tariff, pumped storage costs Rs.6 per unit, while battery storage costs Rs.9 per unit," said Sabyasachi Majumdar, Senior Vice President and Group Head, Corporate Ratings, Icra.

Though the current tariff for RTC projects is higher than for standalone renewable energy projects, the industry anticipates that capital costs for RTC projects will fall in 3-4 years, enhancing tariff competitiveness. However, bid pricing for RE-RTC projects continue to be relatively competitive when compared to traditional generation sources.

Meanwhile, a recent SVJN tender for 1184 MW capacity discovered the lowest price for supplying RTC power at Rs.4.38 per unit. Pumped storage is now more suitable than battery storage due to reduced capital costs, zero import dependency, and a longer lifetime of 30 years. The battery storage system has a maximum lifespan of 15 years, after which there will be replacement and capital charges.

"Despite the pros and cons of battery storage, both pumped storage and battery storage systems are expected to coexist, and we see many developers adopting both technologies." "Both technologies are being promoted by the government," added Kadam. The CEA (Central Electricity Authority) estimates that India would require 40 GW of storage by 2030. Policy and regulatory efforts are moving in the right direction, he says, though implementation may take some time.