Rajasthan faces a problem of high share of solar generation. The State is gearing up to build 75 GW of solar capacity. The power will have to be transmitted over long distances to consumption centres.
The Central Transmission Utility India Ltd, a subsidiary of Power Grid Corporation of India Ltd, proposes to build a high-voltage direct current (HVDC) transmission line between Barmer in Rajasthan and South Kalamb in Maharashtra; it is considering two alternative technologies.
If built with the old, proven line commutated converter (LCC) technology, the cost of the project is estimated at ₹25,261 crore. Alternatively, the modern, flexible voltage source converter (VSC) technology would entail a cost of ₹34,814 crore.
Now, however, there is a new thinking in the National Transmission Committee. Why not bring in battery energy storage systems (BESS) to lower the cost of transmission? HVDC transmission lines are typically designed to handle peak power. But if the peak could be flattened using BESS, an HVDC line could be less pricey.
“As the cost of BESS, based on recent tenders, is observed to be less than the cost of proposed HVDC systems, it is suggested that planning suitable BESS capacity may be explored in the Rajasthan RE complex,” the minutes of the panel’s 29th meeting states.
This, it says, “would provide multifold benefits in terms of transmission system being planned for RE evacuation, providing the necessary flexibility support during the non-solar hours, resource adequacy during non-solar hours and has low gestation period compared to HVDCs.”
The chairperson of the Central Electricity Authority has directed CTUIL to carry out a lifetime cost-benefit analysis of BESS vis-à-vis the proposed HVDC transmission schemes.