The Itaipu Dam (Guarani: Yjoko Itaipu [itajˈpu], Portuguese: Barragem de Itaipu [itɐjˈpu], Spanish: Represa de Itaipú [itajˈpu]) is a hydroelectric dam on the Paraná River located on the border between Brazil and Paraguay. It is the third largest hydroelectric dam in the world, and holds the 45th largest reservoir in the world.

Itaipu Dam
Represa de Itaipú
Barragem de Itaipu
The Itaipu Dam
Itaipu Dam is located in Paraguay
Itaipu Dam
Location of the Dam
Itaipu Dam is located in Brazil
Itaipu Dam
Itaipu Dam (Brazil)
Official nameCentral Hidroeléctrica Itaipú Binacional
Usina Hidrelétrica Itaipu Binacional
LocationFoz do Iguaçu
Coordinates25°24′29″S 54°35′20″W / 25.40806°S 54.58889°W / -25.40806; -54.58889
Construction beganJanuary 1971
Opening date5 May 1984
Construction costUS$19.6 billion (equivalent to $57.5 billion today)
Owner(s)Government of Brazil & Government of Paraguay
Dam and spillways
Type of damCombination gravity, buttress and embankment sections
ImpoundsParaná River
Height196 m (643 ft), reinf. concrete Barrage at Rock side
Length7,919 m (25,981 ft)
Dam volume12,300,000 m3 (430,000,000 cu ft)
Spillway capacity62,200 m3/s (2,200,000 cu ft/s)
CreatesItaipu Reservoir
Total capacity29 km3 (24,000,000 acre⋅ft)
Catchment area1,350,000 km2 (520,000 sq mi)
Surface area1,350 km2 (520 sq mi)
Maximum length170 km (110 mi)
Maximum width12 km (7.5 mi)
Power Station
Hydraulic head118 m (387 ft)
Turbines20 × 700 MW (940,000 hp) Francis-type
Installed capacity14 GW
Capacity factor62,3% (2020)
Annual generation76.382 TWh (274.98 PJ) (2020)[1]

The name "Itaipu" was taken from an isle that existed near the construction site. In the Guarani language, Itaipu means "the sounding stone".[2] The Itaipu Dam's hydroelectric power plant produced the second-most electricity of any in the world as of 2020, only surpassed by the Three Gorges Dam plant in China in electricity production.

Completed in 1984, it is a binational undertaking run by Brazil and Paraguay at the border between the two countries, 15 km (9.3 mi) north of the Friendship Bridge. The project ranges from Foz do Iguaçu, in Brazil, and Ciudad del Este in Paraguay, in the south to Guaíra and Salto del Guairá in the north. The installed generation capacity of the plant is 14 GW, with 20 generating units providing 700 MW each with a hydraulic design head of 118 metres (387 ft). In 2016, the plant employed 3038 workers.[3]

Of the twenty generator units currently installed, ten generate at 50 Hz for Paraguay and ten generate at 60 Hz for Brazil. Since the output capacity of the Paraguayan generators far exceeds the load in Paraguay, most of their production is exported directly to the Brazilian side, from where two 600 kV HVDC lines, each approximately 800 kilometres (500 mi) long, carry the majority of the energy to the São Paulo/Rio de Janeiro region where the terminal equipment converts the power to 60 Hz.



Negotiations between Brazil and Paraguay


The concept behind the Itaipu Power Plant was the result of serious negotiations between the two countries during the 1960s. The "Ata do Iguaçu" (Iguaçu Act) was signed on July 22, 1966, by the Brazilian and Paraguayan Ministers of Foreign Affairs, Juracy Magalhães and Raúl Sapena Pastor. This was a joint declaration of the mutual interest in studying the exploitation of the hydro resources that the two countries shared in the section of the Paraná River starting from, and including, the Salto de Sete Quedas, to the Iguaçu River watershed. The treaty that gave origin to the power plant was signed in 1973.

The terms of the treaty, which expires in 2023, have been the subject of widespread discontent in Paraguay. The government of President Lugo vowed to renegotiate the terms of the treaty with Brazil, which long remained hostile to any renegotiation.[4][5]

In 2009, Brazil agreed to a fairer payment of electricity to Paraguay and also allowed Paraguay to sell excess power directly to Brazilian companies instead of solely through the Brazilian electricity monopoly.[6][7]

Construction starts


In 1970, the consortium formed by the companies ELC Electroconsult S.p.A. (from Italy) and IECO (from the United States)[8] won the international competition for the realization of the viability studies and for the elaboration of the construction project. Design studies began in February 1971. On April 26, 1973, Brazil and Paraguay signed the Itaipu Treaty, the legal instrument for the hydroelectric exploitation of the Paraná River by the two countries. On May 17, 1974, the Itaipu Binacional entity was created to administer the plant's construction. The construction began in January of the following year. Brazil's (and Latin America's) first electric car was introduced in late 1974; it received the name Itaipu in honor of the project.[9]

Paraná River rerouted


On October 14, 1978, the Paraná River had its route changed, which allowed a section of the riverbed to dry so the dam could be built there.

Agreement by Brazil, Paraguay, and Argentina


The construction of the dam was first contested by Argentina, but the negotiations and resolution of the dispute ended up setting the basis for Argentine–Brazilian integration later on.[10] An important diplomatic settlement was reached with the signing of the Acordo Tripartite by Brazil, Paraguay and Argentina, on October 19, 1979. This agreement established the allowed river levels and how much they could change as a result of the various hydroelectrical undertakings in the watershed that was shared by the three countries.

Formation of the lake


The reservoir began its formation on October 13, 1982, when the dam works were completed and the side canal's gates were closed. Throughout this period, heavy rains and flooding accelerated the filling of the reservoir as the water rose 100 meters (330 feet) and reached the gates of the spillway on October 27.[citation needed]

Start of operations


On May 5, 1984, the first generation unit started running in Itaipu. The first 18 units were installed at the rate of two to three a year; the last two of these started running in the year 1991.

Capacity expansion in 2007

The dam undergoes expansion work.

The last two of the 20 electric generation units started operations in September 2006 and in March 2007, thus raising the installed capacity to 14 GW and completing the power plant. This increase in capacity allows 18 generation units to run permanently while two are shut down for maintenance. Due to a clause in the treaty signed between Brazil, Paraguay and Argentina, the maximum number of generating units allowed to operate simultaneously cannot exceed 18 (see the agreement section for more information).

The rated nominal power of each generating unit (turbine and generator) is 700 MW. However, because the head (difference between reservoir level and the river level at the bottom of the dam) that actually occurs is higher than the designed head (118 m or 387 ft), the power available exceeds 750 MW half of the time for each generator. Each turbine generates around 700 MW; by comparison, all the water from the Iguaçu Falls would have the capacity to feed only two generators.

November 2009 power failure


On November 10, 2009, transmission from the plant was completely disrupted, possibly due to a storm damaging up to three high-voltage transmission lines.[11] Itaipu itself was not damaged. This caused massive power outages in Brazil and Paraguay, blacking out the entire country of Paraguay for 15 minutes, and plunging Rio de Janeiro and São Paulo into darkness for more than 2 hours. 50 million people were reportedly affected.[12] The blackout occurred at 22:13 local time. It affected the southeast of Brazil most severely, leaving São Paulo, Rio de Janeiro and Espírito Santo completely without electricity. Blackouts also swept through the interior of Rio Grande do Sul, Santa Catarina, Mato Grosso do Sul, Mato Grosso, the interior of Bahia and parts of Pernambuco, energy officials said.[13] By 00:30 power had been restored to most areas.

Wonder of the Modern World


In 1994, the American Society of Civil Engineers elected the Itaipu Dam as one of the seven modern Wonders of the World. In 1995, the American magazine Popular Mechanics published the results.[14]

Panoramic view of the Itaipu Dam, with the spillways (closed at the time of the photo) on the left
This diagram shows in detail the heights:

325 metres (1,066 ft), entire dam including the 100 metres (330 ft) high Power Line 4 Pylons atop the Barrage
260 metres (850 ft), dam + the foundation inside water until the river floor
247 metres (810 ft), 196 metres (643 ft) high of roof reinforcement concrete dam + Cranes atop the Barrage
225 metres (738 ft), Elevation End Main Concrete Barrage

196 metres (643 ft), The official roof given from Itaipú Binacional Webpage

Social and environmental impacts


When construction of the dam began, approximately 10,000 families living beside the Paraná River were displaced because of construction.[15][16]

The world's largest waterfall by volume, the Guaíra Falls, was inundated by the newly formed Itaipu reservoir. The Brazilian government later liquidated the Guaíra Falls National Park. A few months before the reservoir was filled, 80 people died when an overcrowded bridge overlooking the falls collapsed, as tourists sought a last glimpse of the falls.[17]

The Guaíra Falls was an effective barrier that separated freshwater species in the upper Paraná basin (with its many endemics) from species found below it, and the two are recognized as different ecoregions.[18] After the falls disappeared, many species formerly restricted to one of these areas have been able to invade the other, causing problems typically associated with introduced species. For example, more than 30 fish species that formerly were restricted to the region below the falls have been able to invade the region above.[18]

The American composer Philip Glass has written a symphonic cantata named Itaipu, in honour of the structure.

The Santa Maria Ecological Corridor now connects the Iguaçu National Park with the protected margins of Lake Itaipu, and via these margins with the Ilha Grande National Park.[19]


Central Control Room (CCR)
The dam at night


  • The course of the seventh biggest river in the world was shifted, as were 50 million tonnes of earth and rock.
  • The amount of concrete used to build the Itaipu Power Plant would be enough to build 210 football stadiums the size of the Estádio do Maracanã.
  • The iron and steel used would allow for the construction of 380 Eiffel Towers.
  • The volume of excavation of earth and rock in Itaipu is 8.5 times greater than that of the Channel Tunnel and the volume of concrete is 15 times greater.
  • Around forty thousand people worked in the construction.[20]
  • Itaipu is one of the most expensive objects ever built.

Generating station and dam

  • The total length of the dam is 7,235 metres (23,737 ft). The crest elevation is 225 metres (738 ft). Itaipu is actually four dams joined together – from the far left, an earth fill dam, a rock fill dam, a concrete buttress main dam, and a concrete wing dam to the right.
  • The spillway has a length of 483 metres (1,585 ft).
  • The maximum flow of Itaipu's fourteen segmented spillways is 62.2 thousand cubic metres per second (2.20×10^6 cu ft/s), into three skislope formed canals. It is equivalent to 40 times the average flow of the nearby natural Iguaçu Falls.
  • The flow of two generators (700 cubic metres per second (25,000 cu ft/s) each) is roughly equivalent to the average flow of the Iguaçu Falls (1,500 cubic metres per second (53,000 cu ft/s)).
  • The dam is 196 metres (643 ft) high, equivalent to a 65-story building.[21]
  • Though it is the seventh largest reservoir in size in Brazil, the Itaipu's reservoir has the highest ratio of electricity production to flooded area. For the 14,000 MW installed power, 1,350 square kilometres (520 sq mi) were flooded. The reservoirs for the hydroelectric power plants of Sobradinho Dam, Tucuruí Dam, Porto Primavera Dam, Balbina Dam, Serra da Mesa Dam and Furnas Dam are all larger than the one for Itaipu, but have a smaller installed generating capacity. The one with the next largest hydroelectric production, Tucuruí, has an installed capacity of 8,000 MW, while flooding 2,430 km2 (938 sq mi) of land.
  • Electricity is 55% cheaper when made by the Itaipu Dam than the other types of power plants in the area.


Inside the dam structure

Although its designed peak generating capacity is only 14,000 MW, behind the 22,500 MW Three Gorges Dam, the dam formerly held the record for energy production with 101.6 TWh produced in 2016. This record was beaten in 2020, when the Three Gorges Dam produced a new record 111.8 TWh after extensive monsoon rainfall that year.[22]

In the period 2012–2021, the Itaipu Dam maintained the second highest average annual hydroelectric production in the world averaging 89.22 TWh per year, second to the 97.22 TWh per year average of the Three Gorges Dam in that period.

Annual production of energy
Year Installed units TWh
1984 0–2 2.770
1985 2–3 6.327
1986 3–6 21.853
1987 6–9 35.807
1988 9–12 38.508
1989 12–15 47.230
1990 15–16 53.090
1991 16–18 57.517
1992 18 52.268
1993 18 59.997
1994 18 69.394
1995 18 77.212
1996 18 81.654
1997 18 89.237
1998 18 87.845
1999 18 90.001
2000 18 93.428
2001 18 79.300
2004 18 89.911
2005 18 87.971
2006 19 92.690
2007 20 90.620
2008 20 94.684
2009 20 91.652
2010 20 85.970
2011 20 92.246[23]
2012 20 98.287[24]
2013 20 98.630[25][26]
2014 20 87.8[25]
2015 20 89.2[27]
2016 20 103.1[28]
2017 20 96.387
2018 20 96.585
2019 20 79.444
2020 20 76.382[1]
2021 20 66.369[1]
2022 20 69.873[1]
2023 20 83.879[29]

See also



  1. ^ a b c d "Energy | Itaipu Binacional".
  2. ^ "Energy". Itaipu Binacional. 2014. Archived from the original on 12 April 2014. Retrieved 4 July 2014.
  3. ^ "Number of employees | ITAIPU BINACIONAL". Archived from the original on 2017-02-17. Retrieved 2017-02-16.
  4. ^ Nickson, Andrew (20 February 2008). "Paraguay: Lugo versus the Colorado Machine". Open Democracy. Archived from the original on 3 August 2009. Retrieved 3 August 2009.
  5. ^ Mander, Benedict (20 September 2017). "Brazil's Itaipú dam treaty with Paraguay up for renewal". Financial Times. Archived from the original on 2022-12-10.
  6. ^ "Why Brazil gave way on Itaipu dam". BBC. 26 July 2009. Archived from the original on 26 July 2009. Retrieved 2009-07-26.
  7. ^ Barrionuevo, Alexei (July 27, 2009). "Energy Deal With Brazil Gives Boost to Paraguay". New York Times. p. A10. Archived from the original on August 20, 2017. Retrieved February 24, 2017.
  8. ^ International Engineering Company, Inc. (IECO) was a subsidiary of Morrison-Knudsen. See "Morrison-Knudsen Company, Inc". Baker Library, Harvard Business School. Archived from the original on 2015-03-19. Retrieved 2014-09-28.
  9. ^ Pereira, Fabiano (April 2007). "Clássicos: Grandes Brasileiros: Gurgel Itaipu" [Classics: Brazilian Greats: Gurgel Itaipu] (in Portuguese). Quatro Rodas. Archived from the original on 2007-08-30.
  10. ^ Schenoni, Luis (2016). "Regional Power Transitions: Lessons from the Southern Cone". GIGA Working Papers. Archived from the original on 2018-09-20. Retrieved 2017-03-21.
  11. ^ Abreu, Diego (2009-11-11). "Apagão teve origem em função de condições meteorológicas, diz MME". Globo News. Archived from the original on 2009-11-14. Retrieved 2009-11-11.
  12. ^ "Major Power Failures Hit Brazil". BBC. 2009-11-11. Archived from the original on 2009-11-11. Retrieved 2009-11-11.
  13. ^ Barrionuevo, Alexei (November 11, 2009). "Brazil Looks for Answers After Huge Blackout". New York Times. Archived from the original on August 31, 2017. Retrieved February 24, 2017.
  14. ^ Pope, Gregory T. (December 1995), "The seven wonders of the modern world", Popular Mechanics, pp. 48–56, archived from the original on 2017-03-05, retrieved 2017-09-01
  15. ^ "News & Notes". Water and Energy International. 61 (4). 2004.
  16. ^ Terminski, Bogumil (2013). "Development-Induced Displacement and Resettlement: Theoretical Frameworks and Current Challenges", Indiana University, available at: Archived 2013-12-14 at the Wayback Machine
  17. ^ Switkes, Glenn (2008-03-14). "Farewell, Seven Falls". Archived from the original on 2010-01-21. Retrieved 2010-03-02.
  18. ^ a b Júlio Júnior, Horácio Ferreira; Tós, Claudenice Dei; Agostinho, Ângelo Antonio; Pavanelli, Carla Simone (2009). "A massive invasion of fish species after eliminating a natural barrier in the upper rio Paraná basin". Neotropical Ichthyology. 7 (4): 709–718. doi:10.1590/S1679-62252009000400021.
  19. ^ Teixeira, Cristiano (5 April 2016), Corredor Ecológico de Santa Maria, Paraná – Brasil (PDF) (in Portuguese), Asunción: Itaipu Binacional/MI, p. 3, archived from the original (PDF) on 2016-11-05, retrieved 2016-11-04
  20. ^ "Seven Wonders of the Modern World: The Itaipu Dam". Archived from the original on 2014-01-07. Retrieved 2014-04-22.
  21. ^ "Itaipu binacional – Technical data – Comparisons". Archived from the original on February 16, 2007. Retrieved February 16, 2007.
  22. ^ "Three Gorges Dam sets power generation record in 2020". Retrieved 31 May 2021.
  23. ^ "Energia de Itaipu poderia suprir o planeta por 43 horas" (in Portuguese). Economia – Bonde. O seu portal. 2012-01-02. Archived from the original on 2012-04-17. Retrieved 2012-01-04.
  24. ^ "Itaipú supera récord mundial de producción de energía". Última Hora (in Spanish). Asunción. 2013-01-04. Archived from the original on 2013-01-08. Retrieved 2013-01-04.
  25. ^ a b "Drought curbs Itaipu hydro output". Business News Americas. 5 January 2015. Archived from the original on 8 January 2015. Retrieved 5 January 2015.
  26. ^ "Consumo aumenta e Itaipu supera recorde de 2012". Archived from the original on 2014-01-16. Retrieved 2014-01-14.
  27. ^ "Itaipu superó a represa china en producción de energía". Archived from the original on 2016-01-09. Retrieved 2016-01-07.
  28. ^ "Brasil retiró casi 92 millones MWh de la producción récord de Itaipú". Archived from the original on 2017-01-03. Retrieved 2017-01-02.
  29. ^ {{cite web}}: Missing or empty |title= (help)