Upper Kon Tum HPP which has the total investment of 9,500 billion VND comprises of 2 units with the total installed capacity of 220MW, mean annual power output is more than 1,094 million kWh. This is one among important national projects that PECC1 conducted the investigation, testing, consultancy service for design, construction supervision, grouting construction for dam and headrace tunnel, and preparation of flood control for the downstream areas.
Upper Kon Tum HPP from the top side view
After 10 construction years facing with so many difficulties, the first unit of project has successfully connected to the national power grid. This is the important milestone to complete the commissioning and put the second unit into commercial operation.
PECC1 engineers have applied many new technologies in the process of performing consultancy service in design and construction supervision including tunnel excavation with advanced TBM technology, the first application of air compressed surge chamber technology, etc. The air compressed surge chambers (ACSC) are used as an economical alternative solution for the traditional surface to prevent back water of the pressured tunnel due to load changes in the power plant. This is the first time PECC1 has ever designed the ACSC construction drawings based on the principle of hydraulic calculation and ACSC geometric dimension requested by Multiconsult. The design for construction drawings faced with a lot of obstacles with narrowed access road, ventilation. The tunnel excavation was conducted in so tiny tunnel and lowering excavation was performed in a very hot and less-air situation. The lining steel must be cut into small segments, and then taken inside the tunnel for weld assembly, therefore, the construction condition became more and more difficult. Overcoming those difficulties and obstacles, PECC1’s engineers have completed the works on schedule and with quality.
Waterway scheme with ACSC
The waterway which is about 17.5 km long is the longest headrace tunnel in Vietnam so far, including 5 km is a horseshoe-shaped; the other 12 km is round-shaped with a diameter of 4.5m. The site is located deep in the mountain with many geological layers, complicated faults, the amount of groundwater is very large, therefore, the construction
faces with so many difficulties, especially the construction is blasting excavated conventionally from the intake side. This project has the highest earthfill dam in Vietnam with a height of 80m, and the highest water head in Vietnam with the height of 944m.
PECC1 engineers at the ceremony of 1st unit Upper Kon Tum HPP’s connection to the national power grid
Despite many difficulties, PECC1 engineers performed their tasks perfectly, completing a large amount of work to quickly put the plant into official operation. This further confirms the capability, experience and dedication of PECC1 engineers and enhances the Company's reputation in the energy sector in Vietnam.