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1. What does the Itaipu electricity mean for Brazil and Paraguay?

With more than 20 generating unities and 14.000 MW of installed power, Itaipu provides 10.8% of the energy consumed in Brazil and 88.5% of the energy consumed in Paraguay.

It is the largest clean, renewable energy generator of the planet, having produced more than 2.7 million GWh since it started operating.

In 2016, Itaipu set its best mark for annual energy generation with the production of 103,098,366 Megawatt-hour (103.1 thousand GWh).

2. Where does the electricity generated by Itaipu go?

The flow of energy from Itaipu to the interconnected Brazilian system, from the substation of Foz do Iguaçu, in Paraná, is made by Furnas and Copel, under the coordination of the Operador Nacional do Sistema, ONS (National System Operator). The energy provided in 50Hz uses direct current system of Furnas (DC Link) and the energy in 60Hz uses the 765kV system of Furnas and the 525kV system of Copel. The responsibility of the Paraguayan system is of ANDE, Administración Nacional de Electricidad (National Electricity Management).

3. What is Itaipu's power?

Itaipu's installed capacity (power) is 14 thousand megawatts (MW). There are 20 generating units, 700 MW each.
4. How much did Itaipu's construction cost?

The Fixed Assets in the 2018 Balance Sheet, in the amount of US$ 17.6 billion, may represent the price of Itaipu’s construction.

However, that amount incorporates the financial charges incurred during the construction until each generator unit went online.
By not considering such charges we obtain the Direct Investment, which corresponded to US$ 12 billion in December 2018. Thus, we have that the direct cost of the undertaking would be approximately US$ 854 per kW installed.

The funds raised for the construction, including financial rollovers, totaled US$ 27 billion, in addition to the US$ 100 million in paid-in capital.

5. Which companies built Itaipu?

The construction work at Itaipu was entrusted to consortiums Unicon (Brazilian) and Conempa (Paraguayan), while the electrical-mechanical assembly work was performed by consortiums Itamon (Brazilian) and CIE (Paraguayan). Below are the companies integrating the consortiums.

Unicon: Cetenco Engenharia Ltda.; CBPOCia. Brasileira de Pavimentos e Obras; Camargo Corrêa; Andrade Gutierrez; and Mendes Júnior.

Conempa: A Barrail Hermanos; Cia. General de Construcciones; ECCA S.A.; Ing. Civil Hermanos Baumam; EcomipaEmp. Const. Min. Paraguaya; and Jimenez Gaona & Lima.

Itamon: A. Araújo S.A. – Engenharia e Montagem; Empresa Brasileira de Engenharia S.A. – EBE; Montreal Engenharia S.A.; Sade – Sul Americana de Engenharia S.A.; SertepEngenharia e Montagem S.A.; TechintCompanhia Técnica Internacional; TenengeTécnica Nacional de Engenharia S.A.; and Ultratec Engenharia S.A.

CIEConsórcio de Ingeniería Electromecánica S.A.: AG Brown Boveri & Cie; Alstom Atlantique; Bardella S.A. Indústrias Mecânicas; BSI – Indústrias Mecânicas S.A.; Brown Boveri & Cie. AG; Indústria Elétrica Brown Boveri S.A.; J.M. Voith GmbH; Mecânica Pesada S.A.; Neyrpic; Siemens Aktiengesells-chaft; Siemens S.A.; and Voith S.A. Máquinas e Equipamentos.

6. Is the Chinese Three Gorges power plant larger than Itaipu?

Itaipu Binational is a world leader in clean and renewable energy having produced more than 2.7 million GWh since it started operating.

The installed capacity of Three Gorges Dam is 60% larger than Itaipu (22.400 MW and 14.000 MW, respectively). The Chinese plant has reached a new world record in annual production in 2020, with 111.8 thousand GHh. Itaipu's best mark was in 2016, with 103.1 thousand GWh.

7. Why are there two different frequencies, 50 and 60 Hz, at Itaipu?

Of the 20 generating units, ten generate in 50 Hz, which is the Paraguayan frequency, and ten in 60 Hz, the frequency used in Brazil. On the Brazilian side there is a converting station designed to transform into 60 Hz the electricity generated in 50 Hz and not used in Paraguay.

8. What is the power plant's working life given the sanding-up of the lake?

Geologic studies point towards a working life of at least 200 years.

9. Who benefited the most from the construction of Itaipu, Brazil or Paraguay?

Both countries. With Itaipu, Brazil has developed its own technology to build large dams and incorporated to its electricity sector a power plant that currently supplies nearly one fourth of the entire domestic demand. On its turn, Paraguay now counts on enough electricity to supply its needs for the coming decades without having to make any additional investments in the sector, besides having promoted the development of the entire border area.

10. When did the construction of Itaipu start?

The construction of the power plant is the result of intense negotiations between Brazil and Paraguay, which started back in the 60s. On April 26, 1973, the countries signed the Itaipu Treaty, the legal instrument authorizing them to use the Paraná River for hydroelectric purposes. In May, 1974, the company Itaipu Binacional was created to build and manage the power plant. The first two machines arrive on the job site still in 1974.

11. When did Itaipu start generating electricity?

Itaipu started generating electricity in May, 1984.

12. What does the electricity from one generating unit represent?

With only one of the 20 generating units it would be possible to supply a city with a population of 1.5 million people. The State of Rio de Janeiro could be supplied by the electricity generated by a little more than seven of the Itaipu generating units. The States of Paraná, Santa Catarina and Rio Grande do Sul could be supplied at the same time by less than 13 units.

13. Did the formation of the Itaipu reservoir result in any changes to the area's weather behavior?

A study by the Paraná Meteorology System (Sistema Meteorológico do Paraná - Simepar), which started in September 1997 and finished in 2000, showed that the reservoir does not influence the area's weather conditions. Simepar's study confirmed research done by Itaipu since the reservoir was created. The company monitors all weather events, and no scientific data has been recorded showing weather behavior alterations in the course of all these years after the creation of the reservoir in October 1982.

14. Is the Itaipu reservoir the largest artificial lake in Brazil?

No. Itaipu's reservoir is only the seventh largest in Brazil, which shows a better rate of water use to generate electricity. At Itaipu, the production rate is 10.4 MW per square meter (that is, each 0.10 km² of flooded area generates 1 MW). The Itaipu lake started being formed on October 13, 1982. In 14 days, it was full. Below we compare Itaipu's flooded area and its power to the reservoirs and installed capacity of other Brazilian power plants.

Power Plant Flooded area (km²) Installed capacity (MW)
Itaipu 1.350 14.000
Tucuruí (PA) 2.430 8.370
Porto Primavera (SP) 2.250


Sobradinho (BA)




15. How is the Itaipu Board of Directors selected?

The Brazilian and Paraguayan governments are responsible for appointing Itaipu's executive board of directors. Six directors are chosen by the Brazilian partner, and the other six, by the Paraguayan partner. Board members are also appointed by the governments of both countries. There are 12 board members, six from each country. Directors remain in office for five years, and board members, four.

16. What is energy?

Energy comes from the Greek word energeia, which means “force in action”. There are many energy sources in nature: sun light, wind or water, for instance, are abundant sources that generate clean, non-pollutant energy. In nature, energy is everywhere: in the power of waterfalls, in plants, animals, volcanic eruptions, sun light, wind.

17. How is electricity measured?

Electricity production and consumption are measured in two ways: demand and supply.

Demand is the amount of electricity being generated or consumed at a given time. It is measured in watts (instant demand) or its multiples: kilowatt (kW), megawatt (MW) and gigawatt (GW).

On its turn, electricity is the sum resulting from what was produced over a certain period, a day, for instance. It is measured in watts-hour or its multiples: kilowatt-hour (kWh), megawatt-hour (MWh) and gigawatt-hour (GWh).

18. What is the energy model?

The energy model is the priority given by a country to a certain electricity generation system. Brazil decided that most of the electricity would be generated by hydroelectric power plants. Such power plants are not pollutant because they are water-driven.

19. What is a hydroelectric power plant?

A hydroelectric power plant can be defined as a set of buildings and equipment whose purpose is to generate electricity by using the hydraulic potential existing in rivers.

Hydroelectric generation is associated to the river flow, that is, the amount of water available over a certain time period and at the height of its fall. The higher its fall volumes, the higher its electricity-generating potential. River flows depend on their geological make up, such as width, inclination, soil type, obstacles and falls. They are also determined by the amount of rainfall that feeds them, which makes their electricity production potential vary significantly over time.
The hydraulic potential is established by the hydraulic flow and the concentration of different levels existing along river courses. They can be natural, when the difference in levels is concentrated in a waterfall; or man-made by means of a dam, when small level differences are concentrated at the height of the dam or through the rerouting of rivers from their natural courses, the small level differences being concentrated on such reroutes.

A hydroelectric power plant basically comprises the following parts: dam, water intake and adduction systems, power house, and systems to return the water to the river's natural bed. Each part is a set of buildings and facilities harmoniously designed to operate together.

20. How is hydroelectric energy generated?

At hydroelectric power plants, the water leaving the reservoir is conducted at high pressures through huge pipes up to the power house, where the turbines and electricity generators are installed. The turbine is made up of a series of blades connected to an axis, which on its turn is connected to the generator.

The water pressure causes the turbine axis to turn creating an electromagnetic field within the generator, which then generates electricity. In other words, the hydraulic power is transformed into mechanical power when the water goes through the turbine, causing the latter to turn and, in the generator, which also turns mechanically connected to the turbine, the mechanical power is then transformed into electric power.

21. What are the advantages brought on by the construction of a hydroelectric power plant?

Building a hydroelectric power plant brings on the following benefits:
- Renewable energy;
- Low megawatt cost;
- Clean energy, pollutant-free;
- Job generation;
- Economic and sustainable development;
- It increases the liability of electrical systems.

22. What are the disadvantages brought on by the construction of a hydroelectric power plant?

Building a hydroelectric power plant brings on the following disadvantages:
- Expropriation of productive land by the flooding;
- Environmental impacts, such as the loss of land animals and plants;
- Social impacts, such as the relocation of residents and expropriation of land;
- Interference in fish migration;
- Alterations to river animal life;
- Loss of historic and cultural heritage, besides alterations to economic activities and traditional use of the land.

23. Does Itaipu pay to use Brazilian and Paraguayan waters?

Yes. Itaipu pays royalties for the use of water resources belonging to both countries. From 1985 to 2013, the company has paid approximately US$ 9 billion in royalties to Brazil and Paraguay. The payment is established in Annex C of the Itaipu Treaty. On the Brazilian side, the resources benefit 16 cities, 15 of them in the State of Paraná and one in Mato Grosso do Sul. The royalties are applied to improve the population's quality of life, in education, health, housing and sewer systems.