Bratsk Hydroelectric Power Station

Lore & Background

The Bratsk Hydroelectric Power Station, also known as the 50 Years of Great October Dam, is a concrete gravity dam on the Angara River in Irkutsk Oblast, Russia. It stands as the second level of the Angara River hydroelectric cascade. The dam’s concrete wall stretches 924 meters in length and reaches a maximum height of 124.5 meters, comprising a stationary section, a waterdrop section, and a dumb part. Riverbank concrete walls extend 506 meters, while ground walls on the right and left banks measure 2,987 and 723 meters respectively. The dam’s top carries both a railway line and a vehicle road, though no navigational channels exist due to the Angara’s lack of through ship routes; the design allows for a future ship elevator. The turbine hall houses 18 Francis hydroturbine units, each with a capacity of 250 megawatts, operating under a head of 106 meters. These turbines, produced by Leningrad Metal Works in the 1960s, give the station a total capacity of 4,500 megawatts and an annual output of 22.6 terawatt-hours, making it Russia’s second-largest single hydroelectric producer. Output is distributed via five 500-kilovolt and twenty 220-kilovolt power lines. The plant was designed by Moscow’s Hydroproject institute and is operated by Irkutskenergo, though the buildings are federally owned. A reconstruction project aims to increase output toward 5,000 megawatts, and aging turbines are being modernized. The station powers hundreds of factories, with about 75 percent of its output consumed by the Bratsk Aluminium Plant.

Reader's Guide

The Bratsk Hydroelectric Power Station, a concrete gravity dam on the Angara River, is the second stage of the Angara cascade in Irkutsk Oblast. Upon its commissioning in 1966, it became the world’s single largest power producer, a title it held until 1971. The station houses 18 Francis turbine units, each with a capacity of 250 MW, manufactured by the Leningrad Metal Works in the 1960s. With a total installed capacity of 4,500 MW, it generates 22.6 TWh annually, making it Russia’s second largest hydroelectric producer. The dam’s concrete wall stretches 924 meters in length and reaches 124.5 meters at its highest point, supporting both a railway line and a vehicle road on its crest. The reservoir, formed by a 5,140-meter penstock, is often cited as the world’s second largest by storage capacity. The plant’s output is distributed via five 500 kV and twenty 220 kV power lines. Approximately 75% of this electricity powers the Bratsk Aluminium Plant, and the station is central to the Bratsk territorial-production complex, supplying hundreds of factories. The aging turbines are currently being modernized by Irkutskenergo and JSC Silovii Mashini, with a reconstruction project aiming to increase output to 5,000 MW. The plant’s construction, approved in 1954, was a Komsomol priority and became a symbol of Siberian industrial development, with the city of Bratsk founded concurrently. The first generator began operation in November 1961, and the final unit was commissioned in December 1966.

Did You Know?

• About 75% of the station's output is consumed by the Bratsk Aluminium Plant.

Engineering Scale & Structural Design

The Bratsk Hydroelectric Power Station rises as a massive concrete gravity dam along the Angara River, forming the second step in the river's cascade of hydroelectric installations within Irkutsk Oblast. Crowning the dam, the Taishet-Lena railway line runs alongside a vehicle road, giving the structure a dual transportation function. Although the Angara lacks through-ship routes and no navigational channels exist, the original design reserved space for a potential ship elevator. The dam is frequently cited as the second largest in the world by reservoir storage capacity.

From Blueprint to Commissioning

On December 21 of that year, the Nizhneangargasstroy department—later rechristened Bratskgasstroy—kicked off preparatory earthworks. The project was designated a Komsomol high-tempo priority, placing it under intense public scrutiny and ultimately earning many of its laborers state-level awards.

Industrial Heart of Siberia

From the moment its first generator spun up, the Bratsk station became the electrical backbone of an entire industrial region. Its 22.6 terawatt-hours of annual output feed hundreds of factories across the area, and roughly three-quarters of that energy is consumed by the Bratsk Aluminium Plant alone. The station was woven into what is known as the Bratsk territorial-production complex, a tightly integrated cluster where hydroelectric power and heavy manufacturing depend on one another. For the workers who built it and the communities that grew around it, the station became a defining symbol of Siberia's industrial transformation during the Soviet era.

Global Record and Ongoing Modernization

The entire design was the work of the Moscow-based Hydroproject institute. Today, the joint-stock company Irkutskenergo manages day-to-day operations, though all physical structures remain property of the Russian federal government. Recognizing that the 1960s-era turbines are aging, Irkutskenergo has partnered with JSC Silovii Mashini on a modernization program.

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