Chennai: In a move aimed at strengthening renewable power supply during peak evening hours, Tamil Nadu Electricity Regulatory Commission (TNERC) approved two solar-plus-battery storage projects in the state, adopting a tariff of 4.47 per unit discovered through competitive bidding.The projects, proposed by Tamil Nadu green energy corporation limited (TNGECL) and Tamil Nadu power distribution corporation limited (TNPDCL), will be set up in Karur and Thiruvarur districts under the build-own-operate model.Each project will consist of a 15MW solar photovoltaic plant integrated with a 15MW/45MWh battery energy storage system (BESS). The storage facility will enable the system to supply 15MW of power for three hours during peak demand, allowing solar energy generated during the day to be stored and released in the evening.The tariff of 4.47 per unit was discovered through tenders floated on the state’s e-procurement portal. In the Karur project, Evolve Green Energies Private Limited emerged the lowest bidder, while the Thiruvarur project was awarded to BVG India Limited.According to the commission’s orders, the tariff will remain valid for 25 years and will be paid only for the energy actually delivered to the grid. TNERC imposed several safeguards to ensure consumer protection and prevent misuse of the composite tariff structure. If the battery storage system becomes unavailable, the commission directed that the distribution utility should pay only the benchmark solar tariff discovered by Central or state agencies, whichever is lower, instead of the composite tariff.“The projects will help the State manage evening peak demand, improve grid stability, and reduce reliance on costly short-term power purchases, while also supporting renewable energy targets,” said a TNPDCL official.
