Fourth Extension Hydropower project: Wapda successfully conducts load rejection test of all three units

The Pakistan Water and Power Development Authority (WAPDA) successfully carried out simultaneous load rejection test of all three units of Tarbela 4th Extension Hydropower project. The test was conducted at the load of about 1100MW under the supervision of the consultants and the contractor of the project. The simultaneous load rejection test was aimed at testing the stability of under-water parts and rise in speed and pressure of the turbines. Simultaneous load rejection test is carried out once a hydropower project is complete and its all generating units are fully operational.
Turbine efficiency test was also carried out last week under the supervision of international expert. The test ascertained that the turbine efficiency was more than the efficiency envisaged during the model testing of the turbines.
The completion of Tarbela 4th Extension and Neelum Jhelum Hydropower projects this year has exerted positive impact on overall hydel generation, as it surged to 5241MW during the peak hours yesterday, registering an increase of about 46 percent if compared with 3581MW, generated on this day last year.
Since its commissioning, Tarbela 4th Extension Hydropower project has so far contributed 1.26 billion units of low-cost hydel electricity to the national grid despite low flows of water this year.
The 1410MW Tarbela 4th Extension Hydropower project has been constructed on Tunnel No. 4 of Tarbela Dam. The project has three generating units, each of them having capacity of 470MW. The project will provide 3.84 billion units of electricity on the average to the national grid per annum.
Annual benefits of the project have been estimated at Rs 30 billion. With completion of Tarbela 4th Extension Hydropower project, the installed capacity of Tarbela Hydel Power Station has increased from 3478MW to 4888MW.