HYDERABAD, May 26: One of the four power-generating units of Jamshoro thermal powerhouse has been out of order since it tripped after developing a fault 10 days ago, causing a shortfall of 170 megawatts to the national grid, according to reliable sources.

The powerhouse has four units, three Chinese and one Japan made. The latter can generate around 180 megawatts but the powerhouse authorities have it produce only 110 megawatts while the three Chinese-made units contribute 170 megawatts each to the national grid.

The sources said that the Chinese-generator of unit-II tripped after developing some fault on May 10 and had been out of order since then.

“We have to wait for at least

10 days to let the temperature of the machine to come down to be able to check the fault,” said an official, adding that the machine’s temperature had been normalised now and it would be checked now for faults.

Another official source said that the chief engineer of the powerhouse had formed a committee comprising four senior officials (mostly electrical engineers and operational officials) to check the machine and nature of the fault.

Lahore-based Wapda authorities sought feedback from the powerhouse officials on a daily basis and the local officials could call Wapda experts from Lahore for their help but no such formal request had been made yet, the sources said.

“We may ask someone from Lahore to examine the machine, which tripped all of a sudden while it was in generation process,” said an official.

“The powerhouse authorities had requested for shut-down of the unit-II on account of annual shutdown for maintenance of the unit but unfortunately, this incident occurred and now during the shutdown period the maintenance or overhauling process would be initiated in addition to rectification of the fault,” said an employee at the powerhouse.

The powerhouse authorities normally went for rehabilitation and overhauling of the unit after completion of its 34,000 running hours, said a source.

If they found damage to the unit, the authorities could make claim for insurance through Wapda’s internal insurance payment mechanism and the insurance officials would visit in that case to apprise themselves of the nature and degree of damages.

“No there would be no shortfall of power that is being supplied to Karachi because all the powerhouses of the country are interlinked and it is a proper cycle that supplies power wherever necessary. Then, there is Hubco in Karachi to take care of power supply to the city,” said an official.

However, it was learnt that the 170 megawatts shortfall might lead to low voltage problem in Karachi. The same out-of-order unit had caught fire in December 2006 as well.

According to a source, the rated capacity of each Chinese-unit is 210 megawatts and that of Japanese is 250 megawatts but the powerhouse has them produce 170 and 110 megawatts.

Commissioned in 1990-91, the powerhouse need capacity improvement. It contributes around 600 megawatts to the national grid.