According to the technical design, the water conveying tunnel of Da Nhim Hydropower Plant Extension project is 4,885 m long in total. Up to now, the tunneling work has been completed, technically satisfactory, meeting safety requirements, exceeding the assigned targets, and qualified to move to the permanent reinforcement construction phase.
The project owner will keep on directing the Project Management Board, the supervision consultant and the civil contractor to complete the entire tunnel to be ready for power generation in the third quarter of 2021, with an installed capacity of 80 MW as designed.
Representatives of the project owner, the civil contractor and the supervision consultant performed tunneling rituals in the ceremony - Photo: Ngoc Tuan.
According to Mr. Nguyen Dinh Chien - Deputy General Director of DHD cum Director of the Project Management Board, the construction process has encountered many difficulties such as: the geological condition of the location of water conveying tunnel is more complicated than the design, the Tunnel Boring Machine (TBM) was not working as expected. However, thanks to the support of the Electricity and Renewable Energy Agency (the Ministry of Industry and Trade) and relevant authorities, DHD has implemented solutions to both operate 45 MW of the Da Nhim Hydropower Plant Extension Phase 1 (from the end of 2018), and shifting from the TBM construction method to the conventional explosion and boring method for the remaining tunnel segment (about 929 m). This has enabled the company to both achieve the target of putting the project into operation on schedule and resolve difficulties during the construction of water conveying tunnel. In 2 years (2019 - 2020), the power unit of this project has supplied an additional 380 million kWh to the national power grid.
Da Nhim Hydropower Plant Expansion project has a total investment cost of about VND 1,900 billion, funded by an ODA loan. The project commenced the construction on December 12, 2015. When completed, the total installed capacity of Da Nhim Hydropower Plant will reach 240 MW.
At present, DHD is proposing another extension project of Da Nhim Hydropower Plant with an installed capacity of 80 MW being included into the National Power Development Plan for the period 2021 - 2030, with a vision to 2045 (PDP VIII), to bring the total installed capacity of Da Nhim Hydropower Plant to 320 MW, twice as much as the original design installed capacity, with the aim of taking full advantage of the hydropower potential of Don Duong reservoir.