NEW DELHI: India’s rapid renewable energy expansion is running into a serious bottleneck, with delays in transmission infrastructure forcing large-scale curtailment of green power.According to Ember, an energy think-tank, transmission constraints accounted for nearly two-thirds of the 470 gigawatt-hours of renewable energy curtailed in first quarter of 2026. The problem has become particularly acute in Rajasthan and Gujarat, which host the bulk of India’s utility-scale solar and wind projects. Of the country’s total installed power generation capacity of 543 GW, solar energy accounts for 154 GW and wind, 56 GW.The mismatch between pace of renewable energy deployment and transmission readiness is emerging as one of the biggest operational risks for sector.“India’s renewable energy curtailment arising from transmission constraints is beginning to reach materially significant levels,” said Duttatreya Das, energy analyst at Ember. He said the system would eventually have to move away from “generation-led transmission planning” towards a model where generation and transmission are planned together.An official from the ministry of new and renewable energy, acknowledging that curtailment was becoming a concern, said govt was working on solutions. Large-scale deployment of battery energy storage systems and grid-forming inverters would be crucial for integrating renewable energy into the grid. “We are in regular touch with power ministry and Central Electricity Regulatory Commission for enhancement of transmission capacity,” the official said.As per Ember, India has achieved only about 80% of its annual transmission targets over past five years, leading to a growing backlog. For FY27 alone, the requirement for additional inter-state transmission capacity has been estimated at over 61,000 circuit kilometres.The delays are driven by right-of-way disputes, land acquisition hurdles, forest clearances and supply constraints for critical high-voltage transmission equipment, the report noted.