Major power breakdown hits half of country

ISLAMABAD: Almost half of the country on Wednesday saw around eight-hour power outage, as a major power breakdown in the country’s transmission system occurred in the morning that left Punjab, Khyber Pakhtunkhwa (KP), Azad Jammu and Kashmir (AJK) and Northern Areas without power for almost the whole day. Fortunately, Sindh and Balochistan, constituting the southern part of the country, continued normally.

The electricity transmission system, which tripped in the morning, resulted in power supply failure to the Punjab and KP areas was restored at 5:13pm (after 7:45 hours) with major power generation plants gradually increasing their input in the national grid.

According to the initial reports, the 500KV Guddu-Rahim Yar Khan transmission line tripped at 09:28am along with 500KV Guddu-DG Khan transmission line. As a result, the load increased on 500KV Guddu-Muzaffargarh transmission line from 733MW/72 MVAR to 1,559MW/717 MVAR as recorded at the Muzaffargarh end, this line also tripped. This tripping resulted in under frequency on system from 50.18Hz to 48.755Hz within five seconds. Resultantly, the under frequency schemes came in action and the frequency improved from 48.755Hz to 49.43 Hz.

Meanwhile, some other power stations, including four units of the Chashma Nuclear Power Plant, also tripped perhaps due to the frequency fluctuation, jerk and cascade tripping which started in the northern part from Guddu to Peshawar. The system went under partial failure from Guddu to Peshawar when frequency plummeted down to 45Hz. As soon as the supply failure was reported, the NTDC ground teams were immediately mobilised to check the high transmission lines.

It is important to note that before the tripping, the system had surplus electricity as compared to the demand, therefore, the breakdown was purely associated with the system fault. The breakdown once again exposed the vulnerable transmission system despite the fact that over 10,000MW has been injected into the system.

Little attention towards the upgradation of transmission and distribution system has put the government in the danger zone at a time particularly when only 15 days of the incumbent regime are left. Thecountry is yet to face more hot days in the months to come, but the power system with the installed capacity of over 29,000MW of electricity with feeble transmission and distribution system does not seem to be in a position to smoothly deliver electricity to the end consumers, a senior official privy to the development told The News.

One transmission line of 500KV was not operational in the wake of some technical work owing to which the other lines could not pick the load as demand was on the higher side and it tripped leading to the cascading effect. According to some sources it was DG Khan-Multan transmission line which tripped and led to the breakdown. This also led to the closure of the Mangla, Tarbela, Ghazi Barotha, Chashma and Jinnah hydropower plants, the nuclear power plants and other thermal power plants.

Whenever and wherever the system gets tripped, nuclear power plants are the ones which automatically shut down and they take time in becoming operational as under the SOPs, they ramp up gradually from one MW. Certain sources believe the lack of coordination between the Power Division and the Ministry of Water Resources is also one of the reasons for the failure to make Tarbela and Mangla dams operational on time.

The Secretary Power Division, Yousaf Naseem Khokhar, while talking to The News, said the power supply has started which is now being stabilised. To a question about the reason of the breakdown, he said he had constituted a fact-finding committee headed by Additional Secretary Power Division Waseem Akhtar comprising three system experts. The committee will work on the Terms of Reference (ToRs) which include i) Why the system has failed, ii) How effective efforts were made to restore the system and iii) And finalise the recommendations to avoid such situation in future. The committee will furnish its report to the ministry with two days.

However, Minister for Power Division Sardar Awais Khan informed the National Assembly that various areas of Punjab and Khyber-Pakhtunkhwa, including Islamabad, witnessed a power breakdown due to a reported fault in the Guddu and Muzaffargarh lines. The Wapda spokesman said the power breakdown was not caused due to any fault at any of the Tarbela power plants.

The spokesman said Mangla power plants, Ghazi Barotha, Warsak, Jinnah and Chashma hydropower plants were synchronised and three units of Tarbela have also become operational, while the rest will soon come onstream.