Ust-Ilimsk Hydroelectric Power Plant

one of the world’s largest hydroelectric power plants. Located in Ust’-Ilimsk Raion, Irkutsk Oblast, it is part of the Angara Hydroelectric System. The plant has a design capacity of 4,320 megawatts (from 18 units of 240 megawatts each), an average annual power output of 21.9 billion kilowatt-hours, and a maximum head of 90.7 m. The installation complex includes a concrete spillway dam 242 m long at the crest, with 11 spillway openings designed for a total water flow of 9,700 cu m/sec, concrete station and nonoverflow dams 1,235 m long, earthen dams on the left and right banks with crest lengths of 2.25 km, and a hydroelectric power plant building in unit with the dam, with a length of 396 m. Construction of the complex created the Ust’-Ilimsk Reservoir.

Construction work on the plant was begun in 1963; the first three units were put in service in 1974, and four additional units went into operation in 1975. Electric power generated by the plant is transmitted through high-voltage lines to Siberia’s integrated power grid.