The Water and Power Development Authority in Pakistan says the third and last unit at its 1,410-MW Tarbela 4th Extension Hydropower Project has been synchronized with the National Grid.
This project was constructed on Tunnel No. 4 of Tarbela Dam. It consists of three turbine-generator units, each with a capacity of 470 MW. The project is expected to provide an average of 3.84 billion units of electricity annually to the National Grid. It is intended to help supplement electricity supply during the high-demand summer months, WAPDA says.
Tarbela Dam is on the Indus River and was designed to store water for irrigation, flood control and power generation. The dam is 148 m high and 3,000 m long and has two gated spillways and five tunnels. At the time of the dam’s completion in 1974, tunnels 1, 2 and 3 were scheduled for power generation, while 4 and 5 were designed exclusively for irrigation.
WAPDA says the third unit was operated at various loads up to 466 MW. The unit has now been stopped for technical examination, in accordance with standard operating procedure.
Annual benefits of the project have been estimated at Rs30 billion (US$x). The project will pay back its cost in just three years, WAPDA says.
With this extension, the installed capacity of the Tarbela Hydel Power Station has increased to 4,888 MW.
Work on the project began in August 2013 and under financing from the World Bank.
The first Tarbela 4th Extension unit was commissioned in February 2018.
The 1,410-MW Tarbela 5th Extension project also is under way.