New Delhi, July 30
Holding the northern states responsible for not maintaining grid discipline, top power transmission officials have said that Uttar Pradesh, Punjab, Haryana and Rajasthan continue to overdraw power and this likely led to the massive grid failure last night, the worst in 11 years since 2001.

Top Power Ministry sources told The Tribune today that UP and Haryana were both drawing 20 per cent more power than their allocated quota just before the Northern Grid collapsed this morning. Punjab and Rajasthan followed drawing 5 to 10 pc extra as against their permitted allocation. UP was the worst of the lot drawing a whopping 1000 MW more power than it should have been drawing.

Though the government has set up a committee to ascertain the exact cause of Northern Grid’s failure this morning at 2.35 AM plunging nine states into darkness, top Power Grid officials said that overdrawal of power in the range of thousands of units seemed a reason for Grid failure.

“There was overdrawing of power by Northern states...the Grid can’t be taken for granted,” Sushil Kumar Soonee, Chief Executive Officer, POSOCO (Power Operation System Company) told The Tribune today. Chief of POSOCO, which manages transmission grids in the country, said the transmission lines were stretched. Stretching was to the extent of thousands of units.

When asked what the likely reason for Grid failure

was, Soonee said, "At present we have not arrived at why the failure happened but there was overdrawal and lines were stretched for thousands of units.”.

Asked which states overdrew, Soonee said the overdrawing was in the northern region. “Basically UP, Punjab, Haryana and Rajasthan overdrew. They have been doing so for the past sometime. Full investigation is however to be conducted,” said the top official of POSOCO, the wholly owned subsidiary of Power Grid of India.

Sources said excessive overdrawing of power caused the tripping of the Agra transmission line leading to sudden surge in Northern Grid frequency which exceeded its safe limit resulting in the blackout.

The frequency of the Northern Grid for uninterrupted transmission of electricity is to be maintained between 48.5 to 50.2 Hz and anything above or below that will lead to the Grid failure, as had happened last night.

Asked whether proper mechanisms were not in place and whether this lack of defence mechanisms resulted in Grid failure, Soonee said, “Everyone has to be disciplined. States must come with a balanced portfolio. Elsewhere in the world, there is discipline and everyone adheres to mechanisms in the larger interest."

On whether any lessons were drawn from the last Grid failure around 2010, the Soonee said mechanisms had been put in place. Issues of adherence to mechanisms needed to be looked at, transmission officials said.

“Mechanisms are there but in spite of that...these things happen. We should not take the Grid for granted,” Soonee said.

When questioned on the inadequacy of existing systems and the need to enhance penalties for erring states whose actions cost the nation crores, the top transmission official said these issues would be deliberated upon in the committee set up by the Government. He hinted at the evolution of more stringent mechanisms.

At present, the penalty for an erring state is a meagre Rs 1 lakh.