Oct 2022 blackout blamed on NTDC.

ISLAMABAD -- The country's power watchdog has held the National Transmission Dispatch Company (NTDC) responsible for the partial blackout that occurred in the country in October last year.

Sindh, Balochistan and some parts of Punjab were left without power on October 13, 2022 after a grid failure shut down a number of power stations one by one in a stunning fashion. The breakdown took out about 8,000 megawatts from the national grid, and it took more than 12 hours to restore.

It was Pakistan's third massive power outage in as many years, showing severe complications in the power distribution system of the country.

The National Electric Power Regulatory Authority (Nepra) took notice of the incident and formed an inquiry committee to investigate the matter which on Thursday unveiled its report.

The report said the receiving of a false DTT signal at the 500kV Gatti G/Station from the Ghazi Barotha end initiated the tripping of the 500kV Gatti Ghazi Barotha Circuit-11.

'The blackout was caused by the failure to complete the dedicated transmission line for the evacuation of power from the K2 and K3 power plants.'

The power regulator said tripping of the 500kV K2/K3-NKI T/Line and the 500kV K2/K3-Jamshoro T/Line was due to mechanical failure of the hardware/conductor.

This was a result of improper interim arrangements with non-standard/non-specific hardware material and a lack of periodic maintenance of transmission lines as per standard operating procedures (SOP).

The report said the initial cause of the tripping was overheating and subsequent damage of T-clamps and conductor at the temporary diversion between location number 26A and 27 of the 500KV K2/K3-NKI circuit for the evacuation of power from the K2/K3 plants.

Since the construction of the dedicated transmission line for the evacuation of power from K2/K3 could not be completed by the NTDC, an interim arrangement was made, which is still in place indefinitely as the dedicated transmission line remains incomplete.

This interim arrangement involves a number of joints with different types of clamps, such as T-clamps and L-clamps, based on availability at the time of execution.

Read more: Country incurs Rs100b loss due to power breakdown

The conductor of the transmission lines being used for the interim arrangement is approximately 26 years old and installed in a heavily coastal polluted area, resulting in deterioration.

Initially, a fault developed on the 500kV NKI-K2/K3 circuit due to...