1999 Southern Brazil blackout
Encyclopedia
The 1999 Southern Brazil blackout was a widespread power outage
(the largest ever at the time) that occurred in Brazil
on March 11, 1999. The blackout involved São Paulo
, Rio de Janeiro
, Minas Gerais
, Goiás
, Mato Grosso
, Mato Grosso do Sul
and Rio Grande do Sul
, affecting an estimated 75 to 97 million people. A chain reaction was started when a lightning strike occurred at 22h 16m at an electricity substation in Bauru, São Paulo State causing most of the 440kV circuits at the substation to trip. Brazil was undergoing a severe investment crisis during 1999, which limited spending on maintenance and expansion of the power grid. With few routes for the power to flow from the generating stations via the 440kV system (a very important system to São Paulo state, carrying electricity generated by the Paraná river) a lot of generators automatically shut down because they did not have any load. The world's biggest power plant at the time, Itaipu, tried to support the load that was no longer being supplied by the 440kV power plants, but the 750kV AC lines and the 600kV DC lines that connected the plant to the rest of the system could not take the load and tripped too.
South of São Paulo the consumers experienced an overfrequency, caused because they had more generation than load, mostly because Itaipu was now connected only to this sub-system, but that problem was automatically solved by all generators in the area, that reduced their loads.
The rest of the system experienced a much bigger problem, an underfrequency, since the system had a lot of load and not enough generation capacity. Some generators tripped because of the overfrequency, which aggravated the problem, and after an automatic rejection of 35% of the sub-system load the underfrequency did not go away. This caused the system to break in many pieces, São Paulo and Rio de Janeiro states were split with a few areas remaining online. Most of the Minas Gerais system remained online, and powered Brazil's capital, Brasilia, as well as the state of Goias and some of Espirito Santo.
In Rio the military police placed 1,200 men in the streets to avoid looting. In São Paulo, traffic authorities announced they closed the city's tunnels to prevent assaults. More than 60,000 people were on Rio's subway when lights went out.
At midnight, power began returning to some areas.
Power outage
A power outage is a short- or long-term loss of the electric power to an area.There are many causes of power failures in an electricity network...
(the largest ever at the time) that occurred in Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
on March 11, 1999. The blackout involved São Paulo
São Paulo (state)
São Paulo is a state in Brazil. It is the major industrial and economic powerhouse of the Brazilian economy. Named after Saint Paul, São Paulo has the largest population, industrial complex, and economic production in the country. It is the richest state in Brazil...
, Rio de Janeiro
Rio de Janeiro (state)
Rio de Janeiro is one of the 27 states of Brazil.Rio de Janeiro has the second largest economy of Brazil behind only São Paulo state.The state of Rio de Janeiro is located within the Brazilian geopolitical region classified as the Southeast...
, Minas Gerais
Minas Gerais
Minas Gerais is one of the 26 states of Brazil, of which it is the second most populous, the third richest, and the fourth largest in area. Minas Gerais is the Brazilian state with the largest number of Presidents of Brazil, the current one, Dilma Rousseff, being one of them. The capital is the...
, Goiás
Goiás
Goiás is a state of Brazil, located in the central part of the country. The name Goiás comes from the name of an indigenous community...
, Mato Grosso
Mato Grosso
Mato Grosso is one of the states of Brazil, the third largest in area, located in the western part of the country.Neighboring states are Rondônia, Amazonas, Pará, Tocantins, Goiás and Mato Grosso do Sul. It also borders Bolivia to the southwest...
, Mato Grosso do Sul
Mato Grosso do Sul
Mato Grosso do Sul is one of the states of Brazil.Neighboring Brazilian states are Mato Grosso, Goiás, Minas Gerais, São Paulo and Paraná. It also borders the countries of Paraguay and Bolivia to the west. The economy of the state is largely based on agriculture and cattle-raising...
and Rio Grande do Sul
Rio Grande do Sul
Rio Grande do Sul is the southernmost state in Brazil, and the state with the fifth highest Human Development Index in the country. In this state is located the southernmost city in the country, Chuí, on the border with Uruguay. In the region of Bento Gonçalves and Caxias do Sul, the largest wine...
, affecting an estimated 75 to 97 million people. A chain reaction was started when a lightning strike occurred at 22h 16m at an electricity substation in Bauru, São Paulo State causing most of the 440kV circuits at the substation to trip. Brazil was undergoing a severe investment crisis during 1999, which limited spending on maintenance and expansion of the power grid. With few routes for the power to flow from the generating stations via the 440kV system (a very important system to São Paulo state, carrying electricity generated by the Paraná river) a lot of generators automatically shut down because they did not have any load. The world's biggest power plant at the time, Itaipu, tried to support the load that was no longer being supplied by the 440kV power plants, but the 750kV AC lines and the 600kV DC lines that connected the plant to the rest of the system could not take the load and tripped too.
South of São Paulo the consumers experienced an overfrequency, caused because they had more generation than load, mostly because Itaipu was now connected only to this sub-system, but that problem was automatically solved by all generators in the area, that reduced their loads.
The rest of the system experienced a much bigger problem, an underfrequency, since the system had a lot of load and not enough generation capacity. Some generators tripped because of the overfrequency, which aggravated the problem, and after an automatic rejection of 35% of the sub-system load the underfrequency did not go away. This caused the system to break in many pieces, São Paulo and Rio de Janeiro states were split with a few areas remaining online. Most of the Minas Gerais system remained online, and powered Brazil's capital, Brasilia, as well as the state of Goias and some of Espirito Santo.
In Rio the military police placed 1,200 men in the streets to avoid looting. In São Paulo, traffic authorities announced they closed the city's tunnels to prevent assaults. More than 60,000 people were on Rio's subway when lights went out.
At midnight, power began returning to some areas.