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Monday , July 30 , 2012
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Minister orders probe after north India grid collapse causes 8000mw hole in supply

New Delhi, July 30 (PTI): Power minister Sushilkumar Shinde set up a three-member panel on Monday to find out why the northern region power grid tripped earlier in the day.

The collapse of the Northern Power Grid, which supports 28 per cent of the country’s population, impacted public transport systems including the Indian Railways and Delhi Metro. Normalcy is likely to be restored by the afternoon.

“The fault is not known as yet...Somewhere near Agra, a failure has happened. We will inquire into that,” Shinde said.

Central Electricity Authority Chairperson A S Bakshi, Power Grid Corp Chairman and Managing Director A M Nayak and Power System Operation Corp Chief Executive Officer S K Soonee will make up the panel.

”Right now, we are getting additional 8,000 MW hydro power, including from Bhutan, to meet our demand.”

A grid may collapse when any part supplied by it draws more power than what the system can accept, or if demand falls substantially, and if either of these things happens without adequate notice to the generating units feeding the grid.

“A lot of load has been restored, especially for the essential services such as Railways. The connectivity of thermal plants (supplying power to northern region) to the grid is expected to be fully restored in the next four to five hours,” Posoco’s S K Soonee told PTI. Posoco, a part of the state-run Power Grid, manages the transmission grids in the country.

Power secretary P Uma Shankar said “emergency transmission services are being restored. The work is on and in a few hours, the National Grid would be completely restored.”

According to officials, electricity from the Eastern and Western Grids is being diverted to the Northern Grid. The Northern Grid had last failed in January 2010, because of bad weather.

The northern grid feeds nine regions --- Punjab, Haryana, Rajasthan, Delhi, Uttar Pradesh, Uttarakhand, Himachal Pradesh, Jammu & Kashmir and Chandigarh.

According to the National Load Despatch Centre (NLDC), which is responsible for grid discipline, the northern grid was affected at around 2.35am on Monday.

The normal frequency at which electricity is transmitted through the Northern Grid ranges from 48.5 to 50.2 Hz. At the time of the collapse, the grid frequency was 50.46 Hz, a few notches above normal.

Officials said the power failure affected the operation of about 200 trains.

Delhi government officials were prompt to disown responsibility. “Delhi government or power distribution companies have no role to play in this crisis. It was a major technical fault in the Grid. We expect the situation to be normalised in the next four-five hours (by afternoon),” an official said.

The situation was no different in Punjab and Haryana, where engineers were trying hard to restore the supply, officials said in Chandigarh.

”It is going to take at least four to five hours to restore the power supply in entire Punjab,” said Arun Verma, director in charge of distribution at Punjab State Power Corp Ltd.

Haryana’s special secretary for power, Tarun Bajaj, said that though efforts were on to restore the supply, “it may take few hours to bring situation to normalcy. Every unit takes time to restart”.

In Uttar Pradesh, a top official said that about half of the supply had been restored.

”The power supply, which was severely affected after 2.30 AM due to failure in the Northern Grid has been restored in 50 per cent of the areas in the state”, Uttar Pradesh Power Corp Ltd Managing Director Avnish Awasthi told PTI in Lucknow.

In Rajasthan, the situation had started improving in some parts of the state. Electricity supply had been restored in areas of Jaipur and the supply would further improve due course, an official in the state capital said.

Power Trading Corp Director P S Chandelia said electricity demand in Rajasthan had decreased following rainfall on Sunday night.

NTPC Ltd, the country’s largest electricity producer, said the grid collapse had affected over 8,000mw of its capacity across six power plants.

”We are trying our best to restore the supply from most of our generating stations by the afternoon,” an NTPC official said.

The six affected plants are Singrauli (2,000mw), Rihand (2,500mw), Dadri (1,820mw), Auriya (652mw), Anta (413mw) and Badarpur (705mw).

India has five electricity grids -- Northern, Eastern, North Eastern, Southern and Western. All of them are inter- connected, except the Southern grid.

All the grids are being run by the state-owned Power Grid Corporation, which operates more than 95,000 circuit km of transmission lines. One circuit km refers to one kilometre of electrical transmission line.