The second massive breakdown in as many days was caused by the continuing grid indiscipline on the part of the State Electricity Boards (SEBs) and power utilities that overdrew power from an already overstretched generation system. On 30-07-2012, the northern grid collapsed and it was restored after 15 hours. The Eastern and North-Eastern transmission lines too failed on 31-07-2012 afternoon.July 31, 1.05 PM, and half the nation left powerless, a complete blackout for a second consecutive day and this time, it wasn't just North India, complete blackout in West Bengal, Bihar, Odisha and Jharkhand. But as India faced the world's biggest blackout, Union Power Minister Sushil Kumar Shinde, coming out to reassure the country, "It will be restored in an hour or two."
But even hours after the promise, nothing changed. Meanwhile, conducting a flurry of meetings even as he vowed to take on the states that were overdrawing electricity, "When there is over drawl, such problems arise. In a meeting earlier today I have told my people to punish those who overdraw. I have also given a directive to cut their power supply."
Although the Power Grid Corporation of India Limited (PGCIL) maintained that most areas would see power restored by 7.30 p.m., the situation is expected to become normal only after midnight. The Power Ministry and the PGCIL were unable to pinpoint the cause of the outage. States were overdrawing power was all that they had to say.
Uttar Pradesh, Haryana, Punjab and Rajasthan refused to adhere to grid discipline and continued to overdraw power despite repeated warnings by the Northern Regional Load Despatch Centre (NRLDC) and other State centres, posing a serious danger to the safety of the grid. Even more shocking is the fact that most of these States have refused to install under frequency relays (UFRs) for automatic demand management schemes, which could have prevented such a massive failure. Similarly, the States were found to have overdrawn power when the grid frequency was below 49.5 Hz and even 48.8 Hz, in contravention of the orders of the regulatory authority and load despatch centres.
However, the Punjab government described the charge of overdrawing as absurd, factually baseless and grossly misleading.
Such was the scale of power failure that mining operations in Eastern India came to a grinding halt. Nearly 200 miners were trapped in the Eastern Coalfield at Burdwan in West Bengal and another 65 were trapped in the Bharat Coking Coal facility in Jharkhand.
The grid collapse took place around 1 p.m. affecting Delhi, Uttar Pradesh, Haryana, West Bengal, Punjab, Jammu & Kashmir, Orissa, Bihar, Rajasthan and Assam and the Union Territory of Chandigarh.
The railway network was the worst hit with trains across major parts of the country stopping midway.
This is possibly the first time that all three grids have collapsed simultaneously. Till late in the evening, around 25000 MW of the total 50,000 MW had been restored. About 13,000 MW has been restored in the Northern region and about 4,000 MW in the Eastern region. Supply to the affected regions is being extended from western and southern Grids.
By evening, the hydro stations in the northern region started working and supply has been restored up to Punjab and Haryana.
Source- PTI, Hindu