Map

El Chocón Hydroelectric Complex See map

Technical Data

In 1967 the National Company Hidronor SA began to work on the complex Chocón-Cerros Colorados for the purpose of flood control of rivers, reduce the effects of prolonged downspouts, increase the areas under irrigation and generate electricity.

The artificial lake Exequiel Ramos Mexía, was formed with water from the Limay river. This lake is a water surface of 816 square kilometers (the largest in Argentina) that resembles the great lakes of the mountains. The hydroelectric plant is located at the northern end of the lake above the dam.

Hydroelectric Plant

Installed Power in the Central: 1,200,000 KW
Average annual generation: 3,350 million KW / h
Distance to nearest town: 75 kilometers (Neuquén)
Basin: Negro river 
River: Limay
Volume: 20,600 Hm3
Average flow rate: 713 meters
Type: indoor walk from Dam
Dimensions: length 225 meters, width 26.50 meters 
Bridge cranes: number 2, the main hook 135 tons, auxiliary hook 30 tons

Dam

The dam is made of loose material, with waterproof core and tenon of gravel.
Maximum height above foundation level: 86 meters.
Crest level to sea level: 386 meters.
Total crest length: 2,500 meters.
Base width: 380 meters. 

Exequiel Ramos Mexía reservoir: total volume to 381 masl: 20,200 hm3

Flood Spillway

Maximum discharge flow: 8,000 m3 per second
Total channel length evacuator: 510 meters
Longitudinal slope: 1%
Gates: radio type, number 4, width 16.50 meters, heigth 15.50 meters
Energy dissipating type: dice and stilling basin.

Work-making and leadership

Type: tunnel excavated in rock with steel armor.
Number of channels: 6
Net section of each duct: 78.50 m2, 10 meters diameter
Length: 200 meters

Turbines

Type: Vertical Shaft Francis
Number of Units: 6
Nominal unit power: 200 MW
Nominal net head: 58.40 meters
Impeller: weight 185 tons., diameter 6.35 meters 
Rotation Speed: 88.33 RPM

Generators

Rated up: MVA 222/2262
Total weight per unit: 790 tons
Generator Diameter: 21.50 meters