1968,1986 Guri Dam on Rio Caroni River near Guayana City, VE (Venezuela)

(Satellite)

atkn
In 1986, a $988m expanded the dam from 348' (117m) high and 2,772' (84bm) long to 532' (162m) x 4,314' (1.3km) and added 8gw of capacity.

"Currently, the Guri Dam is the second largest hydroelectric power generation plant in the world after Itaipu in Brazil (BBC News 2006; The World Bank 2006)." Venezuela developed hydropower so that it could sell more of its oil. [pmi]

Because of the word "currently," I looked for a date on the case study. Unfortunately, I could not find one. A quick google search confirmed that Three Gorges Dam is currently (2024) the largest hydroelectric dam at 22.5gw. In fact, as of 2021, Guri Dam is the fifth largest in the world with 10.2gw. [weforum]

Two construction photos from atkn.

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uwm

Construction on the first phase started in 1964 and was completed in 1976 with a capacity of 2gw. New Francis turbines were installed in the 21st Century. "Approximately 73% of the country’s energy requirements are met by the Guri power plant." The country suffered blackouts in 2010 and 2016 because of low water levels. And there was another blackout in 2019 because of a substation failure. [power-technology]

cadswes2 provides a completion date of 1968 for the first phase.

Diego E Garcia posted four photos with the comment:

Construction of the Guri Dam, Venezuela, 1963 - 1986

The Macagua Consortium had a fleet of 325 Caterpillar machines worth $100,000,000 and a diesel consumption of 2 to 3 million liters (528,344 - 792,516 Gallons) per day. 

The machines moved approximately 880,000m³ (1,151,576 yd³) of earth per day.

Please note that this is one of four consortia that participated in the project. More than 200 contractors participated in the gigantic project.

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