ISLAMABAD/Lahore - A major breakdown in the electricity transmission system early Wednesday led to massive power suspension in half of the country.

The main reason behind ‘tripping’ that disrupted electricity supply in Punjab, Khyber Pakhtunkhwa, Islamabad and parts of Azad Kashmir for 10 to 12 hours was yet to be established but the power division constituted a committee to probe the power failure which was the second during the current month and occurred a day before the start of Ramazan.

It was the second massive power breakdown in less than 20 days as the issue of tripping in the national grid continues.

According to initial reports provided by the spokesman Ministry of Energy (Power), the 500KV transmission line Guddu-Raheem Yar Khan tripped at 09:28 am and at the same time 500KV Guddu-DG Khan transmission line also suffered tripping. As a result, load increased on 500KV Guddu-Muzaffargarh transmission line from 733MW/72 MVAR to 1559MW/717 MVAR. After ‘quick’ response by the federal government, the power was gradually restored in around eight hours, the spokesman claimed.

The electricity transmission system has been split into north and south. However, due to tripping, the north side was affected on Wednesday morning resulting in electricity supply failure to Punjab and KP areas which was restored at 5:13 pm with major power generation plants gradually increasing their input in the national grid. At the same time, this line also tripped. This tripping lowered the frequency on system from 50.18Hz to 48.755Hz within five seconds which prompted the under frequency schemes swing into action and the frequency was raised from 48.755Hz to 49.43Hz.

Initially the ministry was of the view that tripping occurred due to a fault at any Tarbela plant which caused the cascade to travel. As a result, Tarbela to Guddu system stopped functioning affecting mainly Punjab and KP. Due to tripping, the north transmission system went off while south transmission system kept on functioning routinely. Later, the spokesman of the ministry clarified that as per signals reported, the fault travelled between Guddu and Muzaffargarh line and no fault occurred at Tarbela.

Meanwhile, some other power stations also tripped due to frequency fluctuation/jerk and cascade tripping started in the northern part from Guddu to Peshawar. The system went under partial failure from Guddu to Peshawar when frequency decayed down to 45Hz, the spokesman said. The southern part of the country, however, remained normal during the entire day which includes Sindh and Balochistan areas. As soon as the partial supply failure was reported, the NTDC ground teams were immediately mobilised to check the high transmission lines, the spokesman maintained.

He said that Power Division also notified an enquiry committee headed by Additional Secretary Waseem Mukhtar to ascertain the causes of tripping, the process of restoration and suggestions to avoid such incidents in future. The additional secretary will be assisted by three experts as member of the committee.

He said before tripping the system was having surplus electricity as compared to demand therefore the temporary loadshedding was purely associated with system fault.

It is pertinent to mention here that on May 1st a breakdown had occurred in the system which resulted in extra unscheduled loadshedding across the country. The 220KV NTDC high transmission circuits, 220KV Daudkhel, 220KV Bannu, 220KV Ludewala and Chashnupp power plants (1,200MW) tripped resulting in supply failure from these plants. The government has yet to share the report about the causes of this breakdown with the public. Breakdown in transmission has become a common feature in the country’s power system and the government even after the passage of five years has failed to control it.

The Nation contacted the NTDC spokesman for comments several times but he didn’t respond.

Although power division officials insisted the reason of breakdown was emergence of technical fault in 500kv transmission line between Guddu and Muzaffargarh power plants, sources described low power generation as main reason behind the suspension.

The electricity generation, said the sources, from hydel, thermal and independent power plants was desperately low against the countrywide demand on Wednesday morning. The wide gap, they said, between demand and supply reduced the electricity frequency at alarming level, forcing power managers to close down the power plants supplying electricity in country’s north. Had the measures to close down the power plants not been taken timely, the entire system could have been collapsed, they added.

“Power production is below than the average due to shortage of fuel to run government-owned generation companies and independent power producers,” they explained.

The country’s power plants are sharing around 14,000MW in energy basket against the overall demand of more than 18,000MW. The “tripping” on Wednesday added another 5,000MW shortfall in national grid, enhancing the total shortfall of around 9,000MW — half of total demand.

Officials said the power plants of Tarbela, Mangla and Ghazi Barotha and four nuclear power plants were closed to avoid any damage after the emergence of technical fault in transmission line.

Zafar Yab Khan, a spokesman for the ministry of energy, said the blackout had hit most of eastern and northern Pakistan after a major section of the national grid “tripped”, or suddenly shut down.

“Due to tripping of a major plant, the north system is off,” Khan said.

He said the cause was not known but was being investigated.

Khan said the problem affected Khyber Pakhtunkhwa and Punjab. Power in the south was not interrupted. Lahore was among the major cities affected. The power was also out in Islamabad.

Media showed pictures of people sweltering at the hottest time of the year in markets and offices.

Earlier, the long ours shutdown disrupted the routine life of millions of people in rural and urban areas. They faced severe water shortage and remained confined to their houses. Thousands could not go to their offices due to unavailability of water in houses. The failure of electricity badly affected life at offices and markets also.

Power Minister Awais Khan Leghari stated a probe will be launched to establish the causes of the breakdown. He also constituted an inquiry committee to look into the power breakdown.



Massive power breakdown hits half of country