【Introduction of the project】
The Asahan No.3 Hydroelectric Power Plant is a run-of-river hydroelectric power plant (174MW, water consumption 106.8㎥ /sec, maximum head 198m) in North Sumatra, Indonesia, using water from the Asahan River,which flows out of Lake Toba (905m above sea level), the world’s largest caldera lake. The project is a yen loan project (ODA) funded by the Japan International Cooperation Agency (JICA).
The project aims to alleviate the tight electricity supply-demand situation in North Sumatra, Indonesia, where new power source development is urgently needed, improve supply stability, and contribute to economic development in the northern part of Sumatra by improving the investment environment. The use of renewable energy will also help reduce the impact on the global environment.
The project addressed technical challenges, such as the construction of Intake Weir and Intake Facilities by diverting Asahan River water more than 100 ㎥ /sec, the optimization of tunnel equipment to ensure tunnel progress, the excavation of large cavern Underground Powerhouse through detailed planning and measurement management, and the use of ICT technology to prevent rework and ensure progress.
The civil works for the hydroelectric power plant, which involved a large construction volume in a single package, including a 10.9 km long tunnel, Intake Weir, Headrace Channel, Headpond, Surge Tank, Tailrace Outfall, Underground Powerhouse, and other structures, with an actual volume of 420,000 ㎥ of concrete, was completed in less than five years, without any delays. As a result, the commercial operation was commenced at the end of 2024, and the project was highly praised by the President of the Republic of Indonesia in the opening ceremony in January 2025.
It also contributed to local employment and human resource development, as well as the transfer and overseas expansion of Japan’s high-quality infrastructure technology.