The Spanish government believes that the massive blackout on April 28, which left the entire Iberian Peninsula without electricity, was caused by errors by the network operator Red Eléctrica and the energy companies. The Deputy Prime Minister Sara Aagesen, who presented a report on the causes, explains that the accident was caused by a surge in voltage that simply could not be resolved in time. This led to a complete shutdown of the system.
This is reported by the Spanish newspaper El Pais.
Vice President and Minister for the Ecological Transition, Sara Aagesen, gave two main reasons at a press conference after the Council of Ministers meeting: a possible planning error by the network operator Red Eléctrica and the malfunctioning of the power plants that were supposed to stabilize the situation. According to her, both factors could have overlapped — both a planning error and technical problems.
Red Eléctrica calculated in advance how much electricity would be needed on April 28th and decided that in case of a surge, ten conventional power plants — gas, coal, nuclear, etc. — should be ready to operate. They were to stabilize the system in the event of an energy surplus.
But on the evening of April 27, one of the companies announced that its station would not be operating the next day. Despite this, Red Eléctrica did not replace it with any other stations, believing that nine other stations would be enough.
The other nine stations also failed to function properly. Aagesen said that each of them somehow failed to do its part and was unable to absorb the excess electricity. This is what led to the accident.
The names of the stations that failed to meet their obligations and the companies that own them are not being made public. However, the fact that some stations did not absorb reactive power as they should indicates the responsibility of the large energy companies: Iberdrola, Endesa, Naturgy and EDP, which own almost all the traditional power stations, writes El Pais.
A cyberattack has been definitively ruled out as the cause of the outage. But the report found several weaknesses in Spainʼs electrical system that could cause problems if a cyberattack were to ever occur.
What happened on the day of the blackout?
The minister emphasized that the reason was not a lack of electricity — there was just enough of it. The problem was the instability of the network, which was caused by a surge.
On the morning of April 28, the system began to experience voltage fluctuations. To stabilize the situation, Red Eléctrica ordered the activation of a combined-cycle gas plant, which is capable of responding quickly in emergency conditions. However, it did not start operating until after 2:00 p.m., when the blackout had already occurred.
One of the main technical problems was the lack of so-called synchronous generation, a type of generation that maintains a stable frequency and voltage in the network. Due to its lack, voltage began to rise uncontrollably in the morning.
Red Eléctrica tried to resolve the situation, including temporarily halting electricity exports to France and redesigning the grid structure. But these actions only worsened the situation and increased tensions even more.
Before the blackout, the voltage in the system remained too high for a long time. This caused massive automatic shutdowns of power plants. Some of them occurred due to technical malfunctions, others without sufficient reason. Aagesen stressed that these unjustified shutdowns only exacerbated the problem, so the companies that operate the power plants also bear responsibility.
Eventually, the outages began a chain reaction that was impossible to stop. Red Eléctrica tried to limit the outages to several regions by making six attempts to reduce the load, but this did not help — the entire system was completely powerless.
The Spanish government does not consider the report on the causes of the accident to be a "judicial verdict", so there is no talk of resignations, for example, of the president of Red Eléctrica, Beatriz Corredor. They are also not publishing the names of the stations that failed to meet their obligations and the companies that own them.
The countryʼs government is now referring the case to the judicial authorities or the Market and Competition Commission (CNMC), which will determine who is specifically to blame and whether there will be compensation for the blackout throughout Spain.
What preceded
A massive power outage hit Spain and Portugal on the afternoon of April 28. Rail services were disrupted, hundreds of flights were cancelled, shops and hospitals were closed. Internet traffic in both countries fell sharply, by 90% in Portugal and 80% in Spain.
Life came to a standstill for a few hours: cash replaced card payments, police used hand signals to direct traffic, and shops, supermarkets and restaurants closed. Madrid firefighters rescued people from elevators 174 times on Monday, and some shoppers stocked up on non-perishable goods.
At the same time, the worst-case scenarios were avoided: Spainʼs nuclear facilities operated safely, and hospitals switched to backup generators.
By the morning of April 29, electricity supply was almost completely restored in Spain and Portugal.
Reuters reported on May 2 that Spain had experienced several power outages ahead of a massive blackout on April 28, and industry officials have repeatedly warned of grid instability. The problems were first reported on April 22.
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