ISLAMABAD: A major breakdown crippled the power system in almost entire Punjab, Khyber Pakhtunkhwa, Azad Jammu and Kashmir and some parts of Sindh and Balochistan for almost eight hours on Wednesday, days before the PML-N government completes its five-year tenure riding on the energy sector’s turnaround story.
The technical fault occurred around usual North-South corridor near the Guddu-Muzaffargarh transmission network at around 9.28am and forced the closure of almost all the power plants in Punjab, Khyber Pakhtunkhwa and Azad Kashmir in a cascading manner within five seconds.
This happened at a time when the entire national grid was being run on an ad hoc basis and no technical hand was at the top to independently take steps for crisis management. The power division initially attributed tripping around ‘Tarbela due to which the cascade travelled’, forcing the system from Tarbela to Guddu to go down.
The position was later changed when challenged by authorities at the Water and Power Development Authority who said there was no issue at the Tarbela station which was producing more than 2,200MW of electricity when “tripped along other power houses due to technical fault in the national grid”.
Wapda said it had restored about 3,000MW generation when given a green signal from the national grid.
Fact-finding committee formed to investigate eight-hour long ‘worst power outage’
“The situation we faced on Wednesday has forced us to reach the facts behind this worst power breakdown. Therefore, we have constituted a fact-finding committee to investigate that why it happened despite system augmentation or up-gradation,” Power Division’s Federal Secretary Yousaf Naseem Khokhar told Dawn.
“The committee will also fix responsibilities and failure (if any) on the part of officials concerned and other technical issues that caused this incident just a day before start of Ramazan,” Mr Khokhar added.
A power division spokesman said Punjab and KP were affected due to power failure while the southern system — Sindh, including Karachi, and Balochistan — remained unaffected. Others in the power sector, however, said some parts of Sindh and Balochistan bordering Punjab and KP also remained off-grid.
The spokesman said in the evening that the “transmission system which split into North and South due to tripping today at 9:28am resulting in electricity supply failure to Punjab and KP areas was restored at 5.13pm with major power generation plants gradually increasing their input in the national grid”.
He said the initial report suggested that 500kV transmission line from Guddu power house to Raheem Yar Khan tripped at 9.28am and at the same time 500 kV Guddu-DG Khan transmission line also tripped.
“As a result, the load increased on 500kV Guddu-Muzaffargarh transmission line from 733MW/72 MVAR to 1,559 MW/717 MVAR as recorded at 500kV Muzaffargarh end. This line also tripped at 09:28:14 hrs. This tripping resulted in under frequency on system from 50.18 Hz to 48.755 Hz within 5 seconds,” he said.
Meanwhile, some other power stations also tripped perhaps 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 at 09:28:59 hrs when frequency decayed down to 45 Hz, the spokesman said.
An expert attributed the breakdown to administrative and technical shortcomings in the power sector. He said the top commander – secretary – of the power sector was a pure bureaucrat without power system experts working under his direct supervision.
The Pakistan Electric Power Company (Pepco) — the so-called umbrella organisation leading the generation, distribution and transmission companies – was led by on acting charge basis by another generalist joint secretary of administrative services Musaddiq Ali Khan as acting managing director.
Also, the post of managing director of the National Transmission and Dispatch Company (NTDC) that directly looked after the national grid was also being looked after by another joint secretary of secretariat group Zaffar Abbas on acting charge basis.
As if that was not enough, the post of NTDC deputy managing director had been lying vacant since April 15 after the retirement of Wajahat Rana. He was the power division’s favourite to come back to run the NTDC but his notification was blocked by the Election Commission’s ban on recruitment.
In the meanwhile, the NTDC board of directors approved with majority the promotion of Ilyas Ahmad, currently heading the national power control centre (NPCC), to take over the post of NTDC deputy managing director but was blocked by the power division to keep the post vacant for Mr Rana.
On the other hand, the technical fundaments of the national grid had come under stress over the past few years because of various reasons, including a declining ratio of hydropower generation that used to be a key stability factor. Instead, accessibility factor of the other renewables like wind, solar and bagasse – also had an impact on the system while the total base load portfolio witnessed a paradigm shift due to heavy induction of electronic equipments that changed harmonics of the entire system.
There was a precarious balance in the system that went under on a first destabilising factor amid suspected system stability and the absence of engineers not in the driving seat.
On top of that, the transmission system in Guddu-Shikarpur-Muzaffargarh portions was still short of optimum strength. For example, the crucial 125kmw Uch-Sibi transmission line was still absent which should have been in place in April 2014 before the commercial operations of the Uch-II power project which former prime minister Nawaz Sharif had inaugurated to demonstrate government’s determination to ease energy crisis, despite repeated warnings from experts.
It was noted that the government will either have to keep one of the two Uch projects closed and pay capacity charges or face repeated outages because the transmission system was simply incapable of evacuating more than 900MW of the two plants.
The power division has constituted an enquiry committee headed by Additional Secretary Waseem Mukhtar to ascertain the causes of tripping, the process of restoration and suggestions for system to avoid such incident in the future.
The additional secretary will be assisted by three experts as members of the committee, the spokesman said, adding that the system had surplus electricity before the tripping as compared to the demand and “the temporary loadshedding was purely associated with system fault”.
The power division has been claiming to have made huge investments in upgrading the transmission and distribution system and introduced safety measures to avoid cascading power breakdowns after repeated such incidents in 2015 and in November last year.
Insiders said there was no need to investigate where the fault occurred but why the protection devices did not deliver. This was because the IT and telecommunication system could precisely record the problem point in milliseconds.
Ali Hazrat Bacha from Peshawar and Khalid Husnain from Lahore also contributed to this report.
Published in Dawn, May 17th, 2018