Author(s): Hirofumi Fujita; Shun Tasaki; Hiromitsu Terasaki; Kunio Yamamoto

Linked Author(s): Hiromitsu Terasaki

Keywords: Kansai Laos Hydropower construction

Abstract: The development and utilization of the hydropower plants is important in achieving the Sustainable Development Goals (“SDGs”). The Kansai Electric Power Co., Ltd (“Kansai”) has been working to repower its existing hydropower plants and to develop hydropower plants in Japan and abroad. With this in consideration, Kansai, as a head shareholder, worked on the development of the Nam Ngiep 1 Plant, and made an important role in introduction of highly reliable equipment for the plant during planning and construction. This paper introduces the construction technologies and management practices for Nam Ngiep 1 Hydropower Plant. The Nam Ngiep 1 Hydropower Plant consists of two dams and power stations, situated on the Nam Ngiep River. Commercial operation commenced on September 5th, 2019. The main power station, which has a 273 MW capacity, exports energy to neighboring Thailand. A re-regulation power station with an 18 MW capacity was built downstream from the main power station to regulate the water level downstream. The re-regulation power station supplies energy for demand in Laos. During the planning phase, owner’s engineers representing Kansai attempted to design an optimum equipment configuration with high reliability in order to realize stable and sustainable operation. Equipment configuration, such as oil supply system and water supply system were designed to decrease power generation outages due to maintenance or accidents. An oil-water separator was installed and non-oil lubricating was applied for runner operating mechanism to prevent oil from spilling into the river, taking environment preservation into consideration. Furthermore, Kansai made efforts toward grid system stability. A governor free, automatic generation control (AGC) system, with automatic frequency control and generating units with black-start capability and line charge capability, was equipped in the main power station. During the construction phase, assembly and installation of electrical and mechanical equipment was carried out in parallel with civil engineering work to shorten the construction term. For example, the stator was assembled inside an air-conditioned vinyl house in order to ensure designated quality. Safety measures, such as monthly safety patrols, were implemented in accordance with the standards of Kansai. Additionally, Hitachi Mitsubishi Hydro Corporation, the electrical and mechanical works contractor, continued to enhance worker safety awareness using safety education and instruction materials in four languages, according to the workers’ nationalities. The above achievements are expected to be useful references for construction technology and management practices in hydropower development to ensure safety and high quality.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022830

Year: 2022