“If a cloud comes over a large solar farm, the grid should be able in an instant to buy power from a stored source — most likely batteries.”
“Our report shows that the cost of renewable electricity and its storage is on a steady decline and could stabilise at around 5 rupees per kilowatt-hour,” said TERI director general Ajay Mathur. “This would enable India to move decisively towards renewables for future generation.” (...) A year ago, a mammoth 420MW solar farm in Rajasthan bid in power at 4.34R/kWh, comparable to the 3-5R/kWh for a new coal plant. Rooftop panels don’t have quite the same economies of scale, but manufacturing costs are falling rapidly. Batteries to store electricity when the sun is not shining will also be critical to end reliance on coal. In its high renewable scenario, TERI assumes the combined cost of clean power and balancing the grid will reach 5R/kWh by 2027. That pathway is “not a certainty” but a “reasonable probability”, the report states.