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According to the official report of the State Grid, the State Grid Brazil Holding Company and the Brazilian Electricity Regulatory Authority signed a concession agreement for the "Northeast Brazil UHV Project" in Brasilia on April 3. This project is the largest transmission concession project in Brazil's history. Today, Brother Electric takes this opportunity to take you to understand the Brazilian power grid.
01Overview of the Brazilian power grid
Brazil is located in the eastern part of South America, with a land area of 8.515 million km2 and a population of about 200 million people. Hydropower resources are abundant and the development conditions are superior, while natural gas and coal resources are scarce and mainly rely on imports. As one of the BRICS countries, Brazil is rich in natural resources and labor resources, and has a high degree of similarity with China in terms of land area, economic size, economic development stage and social and cultural development background.
Geographically, Brazil is located in the eastern part of South America, bordering the South Atlantic Ocean to the east, and bordering other South American countries on three sides, southwest and north, and has rich marine resources. Due to its geographical advantages, favorable economic development prospects and stable legal environment, Brazil ranks first in Latin America and third in the world in terms of renewable energy. In addition, Brazil is one of the largest markets for electricity supply in Latin America when it comes to the power sector.
Brazil's power industry is mainly composed of hydropower, thermal power, nuclear power, and other renewable energy sources such as wind and solar. Among these energy sources, hydropower is the most important source of electricity in Brazil, accounting for about half of the country's total installed capacity. According to data released by Brazil's National Electricity Dispatch Center (ONS), as of August 2023, the total installed capacity of Brazil's electricity system is 213,226MW. Among them, the installed capacity of hydropower is 109,275MW, the installed capacity of thermal power is 40,446MW, the installed capacity of wind power is 28,521MW, the installed capacity of photovoltaic is 10,623MW, the installed capacity of distributed generation is 22,370MW, and the installed capacity of nuclear power is 1,990MW. The installed capacity of various types of power sources accounted for 51.2% of the total installed capacity: hydropower, thermal power 19.0%, wind power 13.4%, photovoltaic 5.0%, distributed power generation 10.5%, and nuclear power 0.9%. The specific data is shown in the following table.
There are 27 large-scale hydropower stations of more than 1 million kW built or under construction in Brazil, among which the Itaipu Binacional Hydropower Station jointly built by Brazil and Paraguay on the Paraná River is the third largest hydropower station in the world today (the world's largest installed capacity is the Three Gorges Hydropower Station on the mainland with 22.4 million kW, and the second is the Baihetan Hydropower Station with 16 million kW), with a total installed capacity of 14 million kW (with 20 units of 700,000 kW).
From the perspective of the structure of Brazil's transmission grid, the country has more than 162,700 kilometers of transmission lines, which are mainly divided into two main camps: the national interconnection system (SIN) and the isolated small grid system. The National Interlink System (SIN) is currently the main transmission grid in Brazil, divided into four systems: Southern, Southeast/Midwest, Northeast and Northern, as shown in the figure below. Brazil's transmission system has voltage levels ranging from 230 kV to 800 kV, covering about 60% of the country's land area and benefiting 95% of the country's population.
(Source: "Brazil's Electricity Market Mechanism, which is dominated by renewable energy, and its implications for the mainland")
02 The current situation and dilemma of Brazil's power grid
In the past 15 years, there have been frequent power outages in Brazil, which have had a significant impact on the lives of local people, and have also hindered Brazil's overall power industry and market economy to a certain extent. Since 2010, the main large-scale power outages are:
1. November 10, 2009: Affected by heavy rainfall and severe weather of thunder, five high-voltage power lines of Itaipu Hydropower Station were short-circuited, resulting in sudden blackouts in Rio de Janeiro and São Paulo, the two largest cities in Brazil, and the surrounding areas. The outage covered about half of Brazil's land area, affecting 18 states, and the grid load loss amounted to 24,000MW, which was about 40% of the total load of the Brazilian grid at the time.
2. February 4, 2011: The misoperation of the switch protection device between a 500kV line and the bus bar led to the bus protection action, and the bus tripping led to the disconnection of the Northeast Power Grid of Brazil and the National Grid of Brazil, resulting in a large-scale power outage in 7 states, with a loss of load of about 2400MW and an affected population of more than 10 million.
3. October 26, 2012: Line cloning and serial faults and substation protection malfunctions caused 9,500MW of load loss in 9 states in the north and northeast, accounting for 88% of the northeast power grid and 77% of the north power grid, and 53 million people were without power.
4. August 28, 2013: The fire caused the double-circuit line to trip, resulting in a loss of 10,900MW of load and 16 million power outages in 8 states in the northeast.
5. September 13, 2016: The two pole lines of a 600kV DC project were tripped one after another, causing the oscillation of the interconnected power grid (ACRO power grid) in the two states in the far northwest, and all the transmission lines in the transmission section were tripped, and the load loss was about 1000MW.
6. March 21, 2018: The circuit breaker overload protection action affected most of the areas (more than 2,000 cities) in 14 states in the north and northeast, and the final loss load was about 21,735MW, equivalent to about 27% of the load before the power outage of the Brazilian national interconnection grid, and about a quarter of the users in the country lost power.
7. August 15, 2023: The overload of the power grid in Ceará and a fault that has not yet been identified by investigators caused a malfunction of line protection, and 25 states in Brazil were without power at the same time, covering almost the whole country, and the entire incident lasted 6 hours and 29 minutes from the occurrence to the end, and the SIN lost load of 19,101MW.
Years of successive large-scale power outages have also exposed the current predicament of Brazil's power grid:
1. The grid structure of the power grid is weak. In recent years, Brazil has vigorously developed renewable energy sources in the field of power generation, mainly hydropower and wind energy. Brazil is rich in hydropower in the north and west, but the southeast coastal region has a high demand for electricity. Therefore, the power grid structure in Brazil presents the characteristics of "north-south power transmission and west-to-east power transmission". With the rapid development of the new energy industry, a large number of wind power installations have begun to be promoted and widely used in Brazil. Therefore, there are great differences in the power grid architecture in different regions of Brazil, and its stability is poor, which is mainly manifested in the insufficient fault carrying capacity of the AC communication channel between regional power grids, which is also one of the root causes of the chain accident of power supply in Brazil.
2. The ability of power technology and power transmission to resist risks is weak. Due to geographical and historical reasons, Brazil's grid architecture and infrastructure are relatively weak, which makes the country face great difficulties in terms of power transmission and energy distribution. Especially in recent years, with the growth of the Brazilian economy, the domestic demand for electricity for life and production has continued to increase. Although Brazil has a favorable geographical conditions for large-scale development of new energy sources, the development and operation of new energy sources in the power sector is not stable. Since the power technology is not yet fully mature, once an accident occurs, the lack of timely and effective response measures may lead to the rapid expansion of the accident or even the collapse of the entire power grid system.
3. The feasibility of privatization of power companies is still questionable. A few years ago, Brazil's Federal Accounting Court approved the capitalization of the Brazilian National Electric Company to encourage and participate in private investment and promote the construction of a completely clean energy chain, that is, the combination of marine wind energy and green hydrogen. However, as of 2022, Brazil's president, Luiz Inácio Lula, has repeatedly made public statements opposing the privatization of the company, proposing during the election campaign to nationalize several previously privatized companies, including power companies.
03 China's impact on Brazil's power grid
Over the past 10 years, State Grid of China has given full play to its advantages in technology, management and brand to help the construction of Brazil's power infrastructure and support the green and sustainable development of Brazil's energy and power, and has established four subsidiaries: State Grid Brazil Holding Company, State Grid Brazil Electric Company (CPFL), China Power Equipment Brazil S.A. and NARI Group Brazil S.A.
Up to now, the power business of State Grid of China in Brazil has benefited 15 states in Brazil, and the 800 kV UHVDC transmission project invested in the construction and operation of the beautiful mountain ± is continuously transmitting clean hydropower from the Amazon basin in northern Brazil to Sao Paulo, Rio and other southeastern power load centers in a long-distance, large-capacity and high-efficiency manner, providing a strong energy guarantee for Brazil's social fight against the epidemic and economic and social development.
Brazil's beautiful mountains ± 800 kV UHVDC transmission project is currently the world's longest distance ± 800 kV UHVDC transmission project, passing through Brazil Pará, Tocantins, Goiás, Minas Gerais and Rio de Janeiro 5 states, 78 cities, the project is divided into two phases, the first phase of the project has been fully put into operation in December 2017, the second phase of the project was completed and put into operation in October 2019, the two phases of the rated transmission capacity of 4 million kW.
The project is the first in Latin America and the fourth in the world to use ± 800 kV UHV DC transmission and transformation technology, and is also China's first overseas UHVDC project.
As for the agreement between China and Brazil on the "Northeast Brazil New Energy Transmission ± 800 kV UHVDC Transmission Project", Brazil's Minister of Mines and Energy Silveira said that the project will play an important role in improving the safe and stable operation of Brazil's power grid, promoting the consumption of wind power and solar energy in northeast Brazil, and will strongly support the green and low-carbon development of Brazil's economy and society. The project will bring together clean energy such as wind, solar and hydropower in the northeast and north of Brazil, passing through the states of Maranhão, Tocantins and Goiás, and can meet the electricity needs of about 12 million people in core areas such as the Federal District of the Brazilian capital, and is scheduled to be put into operation in 2029 with a concession period of 30 years.
This year marks the 50th anniversary of the establishment of diplomatic relations between China and Pakistan, and the signing of the agreement is also an important milestone in the history of bilateral relations. With the support of the two peoples, China is ready to continue to deepen cooperation with Brazil, accelerate the synergy between the Belt and Road Initiative and Brazil's development strategy, and promote the upgrading of bilateral relations on the basis of deepening the comprehensive strategic partnership between the two countries, so as to jointly build a China-Brazil community with a shared future.