High levels of humidity cause tripping – initially 10 out of 64 Grid stations affected; complete restoration in the early hours of Sunday
Karachi, July 12, 2015: K-Electric issued a detailed statement explaining the outage that occurred in Karachi on late Saturday. The outage in Karachi occurred due to a tripping on the Bin Qasim/Pipri 220 KV transmission line due to high humidity levels. The NDTC transmission line faced a similar issue last night as the current humidity levels are up to 99 per cent in the area of Pipri.
Giving details the statement said that around 11th Saturday night the 220kv BQ- Pipri Circuit-4 tripped due to high humidity. There was a breakage of earth wire which also fell on the other Circuit on same tower and tripped it as well. As a result the remaining circuits 1 and 2 also tripped.
With this, South side of KE network disconnected from North side of KE network.
Adding further details the press statement said that following the tripping of the circuits the Bin Qasim power station 2 also tripped, however BQ1 units continued to dispatch.
North side grid were not connected to National grid due to breakdown of 500kv circuits between Dadu and Jamshoroo which occurred on the 7th of July.
KE was also unable to connect South side BQ generation with North side NTDC generation as two critical NTDC 500kv circuits (Hubco-Jamshoro and NKI-Jamshoro) also tripped (due to high humidity) rendering North side system even more vulnerable.
High levels of humidity were a hindrance in the quick restoration process; heavy winds in vast fields deposit excessive dust residue on transmission lines which due to humidity turns into grimy clay like substance. The moist soil cannot be removed until the heat of the sun dries the soil for it to turn into dust again. KE team using its resources at best combat high humidity conditions in restoring power supply to the citizens of Karachi.
KE spokesperson also added, ‘K-Electric has made every effort to rapidly resume power and restored it in the morning and is committed to uphold its promise of quality services in challenging circumstances such as these.