The Son La Hydropower Project is located on the Da River, approximately 360 km northwest of the Vietnamese capital Hanoi. With 2’400 MW this project is the largest hydropower plant in Vietnam.
The project comprises a 138 m high Roller Compacted Concrete (RCC) gravity dam. RCC placing in the dam commenced on January 11th, 2008 and was completed on August 25th, 2010. The RCC volume for the dam is in the order of 2.7 mio m3, which was placed in an effective placement time of 25 months (the RCC block situated in the river was overtopped according to plan during the rainy season of 2009).
The first 1‘000‘000 m3 of RCC were placed by mid of September 2008, only eight months after start of RCC placement in the dam. The peak monthly RCC placement rate was ca. 180‘000 m3/month. The river diversion was closed in May 2010 with partial impounding of the reservoir commenced. A further milestone was the lowering of the rotor of Unit 1 into position on August 20th, 2010. As scheduled, the first 400 MW unit started power generation on December 20th, 2010, with the first power fed into the Vietnamese national grid.
ÅF was sub-consultant to the Vietnamese Power Engineering Consulting Joint Stock Company 1 (PECC1) and responsible for the design of the RCC dam.
Meanwhile, the design works for the 137 m high RCC gravity dam of the 1’200 MW Lai Chau Hydropower Plant, on the same river upstream of Son La, have advanced considerably. ÅF is consultant for the design of the RCC dam for the third largest hydropower plant in Vietnam.
Marco Conrad - Energy Division, Switzerland