Swathes of Punjab and Khyber Pakhtunkhwa have been hit by a massive power breakdown, leaving the national grid with a 4,000 MegaWatt shortfall.

An Islamabad Electric Supply Company (Iesco) official told Dawn that the breakdown occurred when the Tarbela, Mangla and Ghazi Barotha power plants tripped, apparently due to faults in the main transmission line.

Work started on restoring power supply this afternoon, the official said. However, he said, "It will take some time. It could take an hour, two hours to restore."

"Even if we get the supply [up shortly], it will be provided step by step. But so far supply has not been received," he added.

A Power Division spokesperson told RadioPakistan that although power generation had earlier dropped to 11,800MW, it had not reached 12,000MW.

Faults

The Iesco official explained that the National Transmission and Despatch Company's (NTDC) 500KV main transmission line had developed some faults due to which power supply from five distribution companies (Discos) in the north had been disrupted.

Four nuclear power plants at Chashma have also tripped due to tripping of main transmission line of Tarbela, RadioPakistan reported.

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Restoration of power

Attempts were made to restore the Islamabad Electric Supply Company (Iesco) and succeeded 60 to 70 per cent, the Iesco official said, but then Mangla was energised and suspended again.

He said that four to five grid stations have been restored so far.

According to RadioPakistan, the Power Division spokesperson said that parts of Islamabad and Rawalpindi are being energised through power from the central and southern systems, and that power has been restored to 80pc of Islamabad.

The 220KV Multan grid has been restored and gradual restoration of individual 132KV grids and 11KV feeders is in progress, he added.

He also said that Ghazi Barotha had been synchronised and connected to the national grid.

The south system is working and there is no supply failure to Sindh and Balochistan, he told RadioPakistan

Water and Power Development Authority Lahore Kausar Noor Solangi told the state-owned news service that electricity has been restored to parts of Islamabad, Rawalpindi, Muzzafargarh, Multan, Dera Ghazi Khan, Peshawar and Mardan.

A spokesman of the Pakistan Atomic Energy Commission told Radio Pakistan's correspondent that they would be re-connected to the national grid once fault in main transmission line is rectified, and that nuclear power plants take several hours to resume operation once they trip.

According to a WAPDA spokesperson, after restoration of power to the national grid, all of WAPDA's hydel power stations have resumed operations.

"Tarbela, Mangla, Ghazi Barotha and WAPDA's hydel power stations are currently providing the national grid with power in excess of 3,000 megawatts," he said.

Probe into breakdown

Minister for Power Sardar Awais Ahmed Khan Leghari told DawnNewsTV that a probe will be launched to establish the causes of the breakdown.

RadioPakistan reported that the Power Division has constituted an inquiry committee to look into the power breakdown.

The committee, headed by the Additional Secretary of the Division Wasim Mukhtar, consists of three system experts, and will ascertain why the system failed, how effective the efforts to restore system were, and to make recommendations to avoid recurrence of such a situation in future.

Meanwhile, the Senate Standing Committee on Energy has taken a notice of the matter.

Committee chairman Senator Fida Mohammad has decided to write a letter to the Minister for Energy and Secretary Power Division seeking clarification for the breakdown, adding that the facts and reasons behind the current breakdown must be brought to light.

"The breakdown of electricity is the current government's failure," he said, adding that "the breakdown has unveiled the truth behind the government's baseless claims regarding bringing the shortfall under control".