Questions, answers and suspicions after the blackout that left two countries without electricity

On Sunday, June 16th at 7:06 am, a failure of the electrical system that the specialists called "simple" caused a series of events that left almost all of Argentina without electricity, with the exception of Tierra del Fuego. , in Uruguay. and part of Brazil. What happened? How did it happen? What are the guarantees that this will not happen again?

The first answers

On Sunday after 3 pm, Secretary of Energy Gustavo Lopetegui tried a first approach, the system being gradually restored and a little more than half of the country with electricity. "We do not know why it happened"admitted the official, and said that "in the next 15 days"The causes must be known.

The Cammesa report

Shortly thereafter, a preliminary technical report from the company responsible for the administration of the wholesale electricity market (CAMMESA), gave the first details of the cause of the mbadive cut.

According to the report, the interconnected system operates from April 18 with the line Colonia Elía – New Bell, 500 kilowatts (KV), out of service due to the displacement of a tower crossing the Paraná Guazú River. This line brings energy from the Yacyretá and Salto Grande dams in Buenos Aires. A short circuit in the 500 KV line has been added to this event Colonia Elia – Belgrano, parallel to the previous one. "Simultaneously, and for investigated cases, the 500 KV line has been disengaged Mercedes – Colonia Elía"

Cammesa added: "Although the Colonia Elía – New Bell line is not available, the system is ready to resist the disengagement of another 500 KV line, in which case two lines were simultaneously disengaged". With three lines out of service, the system broke down. "This abnormal weakening of the transport network has probably destabilized the Yacyretá and Salto Grande power stations and their contribution has been lost (about 3,700 megawatts)," he continued.

"Even in this case, the system is ready to automatically remove a similar request for lost generation and restore balance almost instantly," continued Cammesa. "Apparently, in this transitional process, other additional generators (including the Embalse nuclear power plant) have disengaged and the entire system has been regained with a generation deficit that has led to its collapse "he concluded. All this happened in a few thousandths of a second, according to Lopetegui.

"This is due to a simple fault in the coastal corridor, on the segment of the railway line Colonia Elía – Mercedes," said Carlos García Pereira, director of Transener, during a dialogue with reporters. "There was a successful reclosing, which means that the line is automatically returned and that it is like there was no breakdown. It's a simple fault, which can be caused by humidity, or by birds nesting on chains of insulators and producing short circuit fugases "he told. "In a few seconds, another similar closure has occurred in Colonia Elía – Campana, the section that continues on the line, but this closure has not come to fruition," he added.

Transener

The first suspicions settled Transener, the energy transmission company, which connects producers to distributors and large users. Transener is a company that controls Pampa Energía, Marcelo Mindlin, and the national state through Ieasa, the old Enarsa.

García Pereira, from Transener, gave more details. The exit of the tower 4 11 (that of the line Colonia Elía – Nueva Campana) occurred because the construction of 120 meters high "risk of collapse".

In parallel, in the last weeks the system began receiving and transporting more energy from Yacyretá and Salto Grande, enjoy the product of greater generation of rains and excess water. Tower 4 11 being out of order, a bypbad was made on 4 12.

Garcia admitted that this may have magnified the problem. "This has brought a much larger flow of energy. If that had not been the case, the contingency of yesterday (Sunday) would have been much simpler ", He said in the dialogue with reporters. "We had a greater flow of energy according to the goal of bring it cheaply"He added.

At his side, the undersecretary of the electricity market, Juan Luchilo, justified this decisionthis ex post could have magnified the problem. "Everything is risky and part of the natural risk of the system, less risk means more equipment, which is an additional cost for taxpayers, the transport system is adequate," he said. .

The restoration of the service

Sunday at 21:35, the Energy Secretariat announced that 100% of the electricity demand had been restored. Monday noon there was 55,000 users of Edesur (the vast majority) and Edesur without electricity in the metropolitan area, according to the National Regulator of Electric Power (Enre), but official sources have indicated that it was not related to the generalized blackout.

A delay in dam operation The Chocón, in Neuquén, service restoration was slowed down in the Comahue region, north of Patagonia.

"The restoration has succeeded"said Luchilo. "In ten hours, most of the country's system was normalized, and today's situation is normal, the generation being restored," he said.

"It's an unprecedented and historic cut. It is not without precedent that there have been regional collapses, but this has been the case throughout the country, "said the official.

L & # 39; investigation

The system had to react to stay in balance and did not, which triggered the mbadive reduction. Although Lopetegui promised that the cases would be known within 15 days, officials and officials of Transener believe that the answer will be provided sooner.

Producers, transporters and other agents in the electricity market must provide Cammesa with detailed information on the activity of the last day. "Technical procedure 11". Cammesa, with its own technicians, companies and independent consultants, will download the report on Enre, which will determine if sanctions are applicable, to whom and of what type.

Cyber ​​attack?

With three lines out of order and no human intervention in the power outage, the government has begun to handle the possibility of a cyber attack since Sunday morning, but technical officials consider it virtually improbable.

"By not checking 100% what happened, we did not exclude anything, but we see it as a technical problem and not a sabotage or a cyberattack"They said.

Can this happen again?

On Monday, Lopetegui stressed Monday that an event like yesterday had "no chance" of recurring. Why such security, if you do not know for sure what caused the flaw?

In principle, the Secretariat of Energy technicians have announced preventive actions exclude a similar fault. For 15 days – the two weeks of the investigation – the operational capacity of Yacyretá and Salto Grande will be reduced and some of its energy will be replaced by that from thermal power plants.

"It will preventively limit the coastal corridor, at the origin of the fault, to avoid any problem, to reduce the risk that in case of failure, there is a similar operational problem, "said Luchilo.In other words, the dams will only provide a smaller fraction of the energy that they can provide at this stage of the year.

The official said that this would lead to a "marginal" increase in the cost of energy, because its production in thermal power plants (gas or LNG) is more expensive than doing it from water, from electricity to electricity. As well as at this time of year, over-supply of hydroelectric power. According to Luchilo, the estimated additional cost for these 15 days is $ 3.5 million. "The system costs $ 9500 million a year," he said. "We have a robust system that allows us to replace one supply availability (hydropower) with another (thermal energy), if we had a limited supply because we could have reduced asks until a few years ago to meet the most stringent security requirements, "he explained.

"We were sure that the operation was safe and reliable casuistry showed us that it was not the case. We must take these measures, even if they have an economic impact, "he added.