Da Nhim Hydropower Plant, a symbol of Vietnam-Japan friendship

Da Nhim Hydropower Plant is one of the first hydropower projects built in our country at the top level, exploiting the great hydropower potential of the Dong Nai River system. The project is considered a beautiful symbol of the Vietnam - Japan friendship.

Young engineers at the Da Nhim hydropower plant. Photo: Nguyen Thao.

Symbol of friendship

Da Nhim Hydroelectric Plant (Ninh Thuan) started construction in January 1962 and lasted until December 1964 with funding from the Japanese Government. The plant has a total installed design capacity of 160 MW, including 4 units, with an average annual electricity output of about 1 billion kWh.

To have the factory as it is today, many young engineers from Japan and Vietnam have laid down their lives. “Although 50 years have passed, the factory’s staff and workers are always grateful to those who have fallen for the electricity of the South,” said Mr. Nguyen Trong Oanh - General Director of Da Nhim - Ham Thuan - Da Mi Hydropower Joint Stock Company.

According to Mr. Oanh, during the war, the factory stopped operating at times because the pipeline was destroyed. During this period, the factory only operated to maintain the generator, providing electricity to South Vietnam with a small output.

After 1975, the local engineers and workers stayed to maintain the factory and technical staff from the North focused on restoring the factory to stable operation within 6 months. This was a very difficult period but demonstrated the ability of Vietnamese engineers and workers.

From 1975 to 2000, Da Nhim Hydropower Plant was an independent unit under Electricity Company 2, then Vietnam Electricity Group (EVN). With the efforts of engineers and workers, the plant maintained stable operations in the context of shortage of materials and equipment, especially during the embargo period, when it was very difficult to import machinery and equipment.

In 1996, the Vietnamese Government decided to spend 66.54 million USD to renovate equipment and lines, of which 7 billion Yen (equivalent to 48.6 million USD) was a preferential loan from Japan, 2.9 million USD was domestic counterpart capital, and the rest was from other international donors.

Since the end of 2000, Da Nhim hydropower plant has merged to form the Da Nhim - Ham Thuan - Da Mi plant cluster, this is a new model developed by Vietnam Electricity Corporation. Promoting the advantages of human resources, management experience and skilled technical staff and workers from Da Nhim to take over the Ham Thuan - Da Nhim plant cluster.

Next, in 2005, the Da Nhim plant was put into restoration after 40 years of operation. The restoration included the following items: replacing the generator stator, bearing supports, excitation system, transformer and generator control system, replacing the turbine, main valve, speed control system, pressure control oil supply system and hydromechanical equipment system, hydrological data collection system and 230 kV Da Nhim - Long Binh line.

The capital was borrowed from the Japan Bank for International Cooperation. The project was completely restored in 2008 with a total amount of 620 billion VND. The contractors selected to implement the Factory Restoration Project include a joint venture between Mitsubishi Corporation and Mitsubishi Electric Corporation of Japan; Sojitz Corporation and Toshiba Corporation of Japan; Tecapro Vietnam Corporation and Vaisala Corporation of Finland. The main consulting contractor of the Project is Nippon Koei Corporation - Japan.

According to Mr. Nguyen Trong Oanh, General Director of Da Nhim - Ham Thuan - Da Mi Hydropower Joint Stock Company, this is a project symbolizing the friendship between Vietnam and Japan. The project has very good and stable construction and equipment quality.

“It can be said that the Vietnamese took over a very advanced project at that time, the management level at that stage was very high. Currently, there are no major problems related to equipment, the generators are mobilized at very high rated capacity, on average for many years, each generator operates from 7,000-8,000 hours/year,” said Mr. Oanh.

Mr. Nguyen Ngoc Quang, former Deputy Director of Da Nhim Hydropower Plant, also assessed that Da Nhim was previously the number 1 hydropower project in Southeast Asia.

50 years still majestic

Up to now, Da Nhim - Ham Thuan - Da Mi is managing and operating 13 units with a total capacity of 642.5 MW. The average annual electricity output is 2.6 billion kWh. On the Pha River, due to the steady flow from Da Nhim, in addition to the goal of supplying water to the Ninh Thuan Delta and Phan Rang City, the potential for hydropower exploitation still exists and with a stable flow like this, I think in the future, it is possible to develop small hydropower plants well behind.

According to Mr. Oanh, for future projects, the Da Nhim - Ham Thuan - Da Mi Hydropower Company has reached an agreement with Jica (Japan) to finance the Da Nhim expansion project with an additional 80 MW generator. The expected start date is 2014, with power generation in 2016. The additional 80 MW will ease the tension in power supply for the southern region.

Mr. Oanh said that the Da Nhim expansion project, currently agreed with Jica, is expected to have a total investment of about 1,900 billion, with Jica funding 85% and the company's counterpart fund being 15%.

Jica has been very supportive, actively sending delegations over for a year to reach a final agreement. It is expected that by the end of September 2013, the loan agreement between the two governments will be signed. Jica representatives visited the Da Nhim-Ham Thuan-Da Mi hydropower plants and highly appreciated the management capacity and quality of the three plants.

Mr. Oanh said that the experience in expanding the plant is due to the trend of hydropower in the future. When the proportion between hydropower, thermal power, and nuclear power is adjusted, then the hydropower plants will be different. For example, at Da Nhim Hydropower Plant, it is almost full-time operation mode, and in the future, it will switch to peak operation. Thus, if there is a need to expand capacity, we can completely continue to expand.

According to tienphong -PH