Power Generation

Hydroelectric units milestone

Installation of an 800 MW Alstom unit at Xiangjiaba power plant

All four units manufactured by Alstom for China’s Xiangjiaba underground hydro power plant have now successfully entered commercial operation. These 800 MW class units coupled with an 889 MVA generator are the most powerful hydroelectric generating units in the world. Each unit is able to supply the electricity consumption of approximately five million inhabitants during a year.

The four units were designed and manufactured in Alstom’s factory in Tianjin, China, and delivered in a record time for such large machines – at an average of one unit every two months. After a first phase of reliability trials, the units began successively commercial operation between November 2012 and June 2013.

Each unit for the Xiangjiaba plant includes an 800 MW class Francis turbine coupled to an 889 MVA generator. The generators are the only air-cooled generators in the world with 23 kV windings. This high voltage allows an optimised electrical design for such a high power output. At almost 10 m in diameter, the turbine runners weigh over 400 tonnes.

With a total capacity of 6 400 MW, the Xiangjiaba power plant will run on eight units. When completed, Xiangjiaba will be the third largest hydro power plant in China and an important power source in the country’s West to East Electricity Transfer Programme to satisfy the growing electricity needs of the country’s eastern provinces.

AN ACHIEVEMENT
“The successful delivery and commercial operation of the four units for Xiangjiaba plant represent another important milestone to showcase Alstom’s contribution to China’s hydro power development,” said Yves Rannou, general manager of Alstom Hydro China.

Located in southwest China Jinsha River, the Xiangjiaba power plant is owned by the China Three Gorges Corporation (CTG). The Xiangjiaba project is one of a series of successful co-operation ventures between Alstom and CTG, which include deliveries of Three Gorges Left Bank (eight units of 700 MW), Three Gorges Right Bank (six units of 700 MW) and Three Gorges Underground (two units of 700 MW).