A collapse of the North-Eastern Grid in December was kept as a well-guarded secret due to the forthcoming assembly elections in the three north eastern states of Meghalaya, Tripura and Nagaland.
The collapse, which occurred within six months of India's worst blackout in July 2012, was kept under the carpet by the government authorities even as it caused a load loss of over 1,000 MW. A recent letter from the power ministry to the cabinet secretary, Ajit Seth and the Prime Minister's Office (PMO) spilled the beans.
"On December 14, 2012 at 1040 hours, the 220 kV Balipara-Samaguri (flow 60 MW) tripped at Samaguri end. Simultaneously 315 MVA ICT-I (flow 148 MW) at MISA also tripped," the letter said.
"Due to tripping of these elements, the North-Eastern Region (NER) Grid comprising of part of Assam and Arunachal Pradesh, Meghalaya, Mizoram, Nagaland, Manipur and Tripura, separated from the North-Eastern-Western Grid (that carries a load of around one lakh mega watt), collapsed on load generation mismatch," the letter added.
Sources in the power ministry said the NER system restored in an hour and the total generation loss was 553 MW and load loss was 1,023 MW.
A senior official of the National Load Despatch Centre, the apex body monitoring and controlling the country's grid operations, confirmed of the grid failure and said that massive investments are already underway to upgrade transmission lines and the faults that led to the collapse cannot be ruled out despite the 24 hour monitoring.
Power ministry officials said that the Planning Commission has also been stressing on the need to initiate steps to prevent the kind of grid collapse that occurred in July.
In a letter to the ministry a few months back, it had said that the grid collapse had received disproportionate publicity globally, highlighting that 600 million people deprived of power for several hours. It had also asked the ministry to make some systemic changes that may even involve amendment of the Electricity Act.
"The need to do so is especially urgent because we have been moving towards a nationally integrated grid….the Southern region is not integrated, and the other regions are integrated and together they are the largest integrated grid in the world," the letter had said.