BarcelonaIn the absence of further details to explain the unprecedented blackout that hit the Iberian Peninsula yesterday, this unprecedented outage has raised questions among the energy expert community, who are trying to analyze what happened this Tuesday. ARA has consulted with industry specialists to understand the causes of the incident. Some of them also point to deficiencies in the system.
What caused the blackout?
For now, Red Eléctrica has explained that the Spanish system collapsed in a span of five seconds, following two disconnections that wiped out 60% of electricity generation. Marta Marsó, a technician at the Community Transformation Office of the Catalan Association of Municipalities, points to a mismatch between the instantaneous energy supply and demand. "This means there is a deviation from the forecast that was made and that it has exceeded the corrective adjustment mechanisms. Although various adjustment mechanisms are in effect, and the probability of this occurring is very low, we are in a stressed grid and there is no guarantee that it will recur," explains the environment.
For the president of the Efficient Energy Cluster, Joaquim Daura, there are still few answers to attribute a clear cause to the blackout. "If we had been asked on Sunday or Monday morning if this could happen, we would have said the chances were remote," he admits. Even so, remember that the energy generation system has changed a lot in recent years, with the increased use of renewable energy—especially photovoltaic and wind—and that these have less predictable behavior than other energy sources. "What this imbalance demands of us is that as we move forward with renewables, we must be able to manage these jumps and this uncertainty. Until now, since we had few very large plants, we could play with generation based on our consumption. But you can't tell the wind to blow less or the sun to come out," says Daura.
Sabrina Lavado, associate attorney at the energy law firm Verdia Legal, points out that this is likely a "concatenation of different events." "We are exercising caution. This is completely unprecedented, and we must send a message of security and peace of mind regarding supply," she indicates.
Was the electrical system prepared?
CSIC research scientist Antonio Turiel points to a problem that has been talked about "for years": grid instability. "Imagine the game of jump rope, which keeps turning. Every time you add an electricity production system, you put more force on the rope, and everyone has to enter perfectly coordinated [to avoid falling]. The problem is when everyone enters at the same time, and the photovoltaic system adapts very poorly." The expert asserts that photovoltaic power was the energy source that fell most drastically yesterday and says that energy companies should have incorporated stabilization systems to avoid a blackout of this magnitude.
On the other hand, Marsó asserts that the system itself is "not very flexible" and that rapid response should be improved. "We've gone from a one-way system, with few and very large generators, to a much more heterogeneous and distributed one. This is a huge change in the electricity market, and it hasn't been accompanied by the necessary reforms to enable the grid to cope," he emphasizes. He insists on not blaming renewables for these imbalances: "The ecological transition must take place, but with all the necessary safeguards."
Would more storage have helped?
"What happened reinforces the importance of what we've been talking about for many years: the need to have decentralized generations, communities that produce energy and can store it," emphasizes Esther Izquierdo, former president of the Efficient Energy Cluster of Catalonia and director of innovation at the engineering group Wattega. She recalls that, as was the case with key infrastructure such as hospitals and airports, some businesses also continued to have electricity because they had generators and argues that the system must continue to advance in that direction.
Marsó agrees on the need to increase the installation of batteries, both large and small, to increase energy storage capacity in Catalonia. "This is also true with the lines of alternative systems that have emerged and that can complement the range of solutions, such as CO2 batteries."2 or hydrogen," he adds, in addition to having more reversible systems such as hydroelectric plants.
Turiel also blames the electricity companies for not having their combined cycle plants - which use gas and steam turbines to produce electricity - activated to support in an emergency. "stops," he criticizes, and attributes this to the fact that yesterday electricity prices were at negative levels and were not profitable for companies in the sector. In this sense, Daura explains that these support plants may be stopped and receive the order to start them up when an imbalance between generation and consumption is expected. But the fact that the cut was so gradual and .
What investments are pending?
Electra Caldense's technical and commercial director, Anna Domenjó, says that for years there has been a call for "more robust grid." "The systems are old, and investment in digitalization is needed to adapt them to new technologies," she explains. The sector is also waiting to implement system aggregators, a mechanism that should help regulate demand: for example, by facilitating the reduction of consumption by large producers, such as factories, during peak hours, in exchange for compensation. Investment, Domenjó adds, must also be invested in the physical infrastructure: "This is provided by the State; here, distribution companies are hamstrung because they depend on it."
Why didn't it affect the rest of Europe?
One of the peculiarities of the Iberian Peninsula is that until recently it was an energy island. Due to its characteristics, Spain is only connected by France and Morocco. Currently, the connection rate is at 3%, whereas the European Union (EU) recommends 10%. As Marsó points out, the structural improvement in interconnections increases exchange capacity and, therefore, increases supply guarantees and provides greater flexibility to the electricity market. "Improved interconnection would possibly have facilitated our system recovery, but what is certain is that it provides greater security and continuity of supply, increases market efficiency and competitiveness, and also facilitates greater integration of renewable energies," explains the expert.
Can a meteorological phenomenon cause such a blackout?
The State Meteorological Agency (Aemet) has already confirmed that no unusual meteorological or atmospheric phenomenon occurred on Monday that could have caused a power outage of this magnitude. None of its weather stations detected sudden temperature fluctuations that could explain the power outage, although there was speculation that a severe atmospheric disturbance—such as a solar storm—could have caused an overload of the power grid.
Turiel believes it's unlikely that a meteorological phenomenon alone could cause such cascading damage. "It can happen and can add instability, but the grid has resilience mechanisms and is prepared to overcome it. It's not exceptional."
Bogas (Endesa) asserts that the closure of nuclear plants will have a "significant impact" in Catalonia.
Endesa CEO José Bogas once again advocated extending the lifespan of nuclear power plants and warned of the "significant consequences" for Catalonia: "Sixty percent of the region's electricity generation comes from these plants," Bogas recalled. "In this context, a review of the nuclear plant closure plan in Spain would be prudent. Today, this is an energy source we shouldn't do without," the executive argued, while also calling on the Spanish government to review the taxation of nuclear power plants.
In November 2027, the nuclear reactor at the Almaraz 1 plant in Cáceres is expected to be shut down. The Almaraz II reactor will be shut down a few months later, as outlined in the plan agreed upon by the Spanish government, through Enresa, and the companies that own the plants. The timeline calls for the complete elimination of this source of electricity by 2035, when Vandellòs II is shut down.
