KARACHI, May 20: Several areas in the city remained without electricity on Monday due primarily to rise in temperature.

In a press release issued on Monday, the Karachi Electric Supply Corporation reiterated that the power supply system had not collapsed and the power utility was supplying electricity normally to the city.

Sources in the KESC told Dawn that complaints of power failure had been received from Federal B Area, Gulistan-i-Jauher, Gulshan-i-Iqbal, North Nazimabad, Nazimabad, North Karachi and Defence Housing Authority.

A resident of Federal B Area, Block 9, said it was beyond his comprehension why power supply repeatedly goes off in his area for five to 10 minutes only. “Such power breakdowns are very bad for home appliances.” Similarly in Block 7, F. B. Area power breakdowns are a routine and about 20 breakdowns occurred in a day. Electricity goes off after every 20 to 30 minutes on an average.

A resident of North Karachi, Sector 11-B, said her locality had been without electricity from 11am to 3pm.

Quoting a KESC spokesman, the press release said the power supply system of Karachi had no comparison with power utilities of the developed and industrialized countries.

“The power system in those countries also experiences breakdowns but the same is not felt at the consumer-end due to automatic alternative and parallel system from generation to distribution. With fault in one line supply to a consumer is automatically and instantly shifted to the parallel supply source and utility-users do not feel the breakdown.”

While local electric supply is through single source and any disturbance at generation, transmission or distribution stage breakdown is also experienced at consumer-end.

“Electricity consumers and media must understand that the weather also affects the power supply system in other countries. As hot weather affects the system, similarly snowfall and snow-rain disturb electric supply of cities in the USA,” the KESC spokesman said.

“Fog causes extra-high-tension tripping in coastal regions of the USA and the Middle-East,” he said.

“The only method of beating the heat and increasing power supply efficiency during high temperatures is to air-condition the 51 grid stations of the KESC. Saving the power transformers and feeders from high temperatures will prevent overheating of machines and increase efficiency by 20 per cent to 30 per cent; tripping and interruptions will also become rare during hot summers,” the spokesman explained.

He said that KESC had only one air-conditioned grid. ”Recently, the control rooms of about 13 grids were air-conditioned. Paucity of funds deters the corporation from immediately spending large sums of money on central air-conditioning of all grid stations. The installations are cooled through additional exhaust and other fans at the moment; hence abnormal temperatures over-heat the feeders and switches at supply stations, which in turn stop supply power, he added.