Brasília – The executive secretary of the Brazilian Ministry of Mines and Energy, Márcio Zimmermann, stated this Wednesday (11th) that the power outage that left ten states of Brazil in the dark was caused by adverse weather conditions. In a press conference this morning, he claimed that the problems occurred in three transmission lines, which receive electric power from the Itaipu hydroelectric plant, in the state of Paraná. Yesterday (10th), at 10:13 pm, a failure in the Brazilian interconnected power system led to a domino-effect blackout, which also affected the power system in Paraguay, where the energy supply was interrupted.
According to the secretary, the failure hit two lines that connect the city of Ivaiporã, in the centre of the state of Paraná, to Itaberá, in the south of São Paulo, and another line, at a station linking Itaberá to Tijuco Preto, also in the state of São Paulo.
The secretary informed that the power supply returned to normal four hours after the onset of the blackout, which took place at 10:13 pm on Tuesday (10th). “No equipment has been damaged. There was a very strong [cold] front, with intense winds and rains, concentrating in Itaberá,” he explained. The city receives circuits from the Itaipu hydroelectric plant and redistributes power to other regions.
Zimmermman underscored, however, that the causes of the blackout have not been ascertained precisely yet. The origin of the problem should be presented at a meeting scheduled for 05:00 pm, at the National Power System Operation Centre (CNOS).
"It was a disturbance. Now, a thorough analysis of the field is underway at the National System Operator (ONS). The minister called an emergency meeting of the Electric Sector Monitoring Board, to be held today at 05:00 pm," said Zimmermann. "There is an ongoing effort in the sector to analyze the causes and take the necessary measures in order to minimize this type of situation," he finished off.
Without pointing out the exact cause, the executive secretary stated that the problem may have occurred after the system activated its defence mechanisms. "The entire power transmission system creates a situation that may lead the circuit to disable a line with no consequences. In this case, we have had a triple contingency. In order to protect itself, the system sets in motion a series of protection mechanisms. Proof of that is the fact that four hours later, the entire system was on again in Brazil," he said.
Zimmermann also ruled out the possibility that the problem may have been caused by sabotage, the secretary denied. According to him, the power system is always liable to be affected by this type of problem. "Our country currently has the most interconnected system in the world. Brazil is investing heavily in a robust transmission system. We have increased the interconnectedness," he claimed.
To the professor at Coppe, in Rio de Janeiro, Luiz Pinguelli Rosa, the important thing is to increase investment in intelligent systems that are able to isolate the problems and prevent a domino effect such as the one that took place yesterday. "We need to invest in long distance transmission lines in order for our networks to be more efficient," he explains. According to Pinguelli, Brazil virtually has a "hydroelectric Saudi Arabia in the country," but nevertheless there must be other power generation sources, and these must be located closer to the large centres.
The blackout of 2001
Zimmermann ruled out any similarity between the 2001 blackout, which resulted in the implementation of power rationing in the country, and the one that took place last evening. "The situation that we had in 2001 was one of power shortage. What we had just now is a situation in which there are no power shortage issues, it was an electric problem that caused this disturbance," he explained.
According to him, eight years ago, there was a lack of investment in the Brazilian electric industry. "We did not have the necessary investment in transmission and generation, and that led to the situation in which the country had to ration electric power. It was a continual problem, because the generation was not sufficient to meet the demand."
In the morning on Wednesday, the Furnas Centrais Elétricas power company informed that the transmission lines connecting the Itaipu plant to the National Interconnected System (SIN) are operating normally, and no damage whatsoever has been done to the circuits and transmission towers.
Itaipu
Late last evening (11th), the Itaipu Binacional hydroelectric plant informed that the blackout, which occurred in several states in the Southeast and Midwest regions, did not originate in the plant. According to a press release, the most likely hypothesis is that some accident affected one or more points in the power transmission system, including Furnas, which is responsible for transporting the energy from Itaipu to the South and Southeast.
The release confirms that immediately after the blackout, the machinery at the plant were working, “spinning out in the empty, but unable to transmit power, because the transmission lines that link Itaipu to the Brazilian system were disconnected.”It also informs that after 15 minutes, the Paraguayan system was already being supplied by Itaipu, further supporting the hypothesis that the cause of the malfunction was located outside the plant.
In the morning, Itaipu Binacional informed that it has returned to operating in normal conditions starting at 06:00 am. With 20 generating units and 14,000 megawatts of installed power capacity, the binational plant supplies 19.3% of the power consumed in Brazil, and 87.3% of power consumption in Paraguay. Itaipu is the second largest hydroelectric plant in the world, second only to the Three Gorges Dam, in China.
The company states once again that it does not possess information on what may have caused the blackout that occurred in several states of the Southeast and Midwest regions, but rules out the possibility that it originated at the hydroelectric plant.
*With information from news websites G1 and Agência Brasil. Translated by Gabriel Pomerancblum
