New Delhi, Dec. 26 -- King Coal is tightening its grip as discoms flock to thermal power while cheaper green power waits for buyers, raising questions over India's ability to meet its energy transition goals.

States such as Madhya Pradesh, Bihar, Assam and West Bengal have recently signed power purchase agreements (PPAs) for thermal power at tariffs of as much as Rs.6.64 a unit, even though solar and wind power come for Rs.2.5-4. The key reason is the 'infirm' nature of renewable power - lack of generation when the sun doesn't shine, and the wind doesn't blow.

Even those renewable projects with combined solar and wind generation, plus battery storage, are not finding takers despite being available at Rs.5 a unit or lower, as discoms rem...