Long queues outside corner shops and bakeries. Supermarkets closed. Anxious people carrying gas cylinders, bags of charcoal, batteries, and candles. In an instant, and for several hours, the fast, digital rhythm of 21st-century life was unplugged. 

The unprecedented Iberian blackout that left Portugal and Spain “in the dark” on the morning of April 28 exposed just how reliant modern society is on the seamless functioning of our electrical grids. 

In the weeks that followed, the event triggered international media attention, quickly becoming politicized and a lightning rod in the renewable energy debate, as the Iberian Peninsula is one of the world’s regions with the highest levels of renewable energy production.

Experts across the sector, including INESC-ID researchers and Instituto Superior Técnico professors Pedro Carvalho and Rui Castro, helped clarify the technical complexity of the event and the deeper challenges it revealed for Europe’s ongoing energy transition. (Read our earlier article here.) 

“It immediately caught the world’s attention. Because we have one of the highest shares of renewables, what happened here became a weapon in the political debate.” –  Pedro Carvalho 

But now, the key question is: how do we prevent this from happening again? 

Events like these are often compared to forest fires — all too familiar in Portugal. Once they begin, they are incredibly hard to stop. Which is why building resilience and improving control in such a tightly interconnected system is essential. 

That’s precisely the focus of a new project titled “Assessing and Mitigating Blackouts: The Case of Iberian 2025 Blackout”, recently awarded a US$200K seed grant by the MIT Portugal Program. The MIT Portugal Seed Fund is awarded exclusively to MIT Principal Investigators, with proposals that include collaboration with Portuguese faculty, students, industry, or other institutions in Portugal. 

The project is co-led by Marija Ilic, professor and researcher at MIT and Pedro Carvalho—long-time collaborators with nearly two decades of joint work on modelling power systems and grids. Their research will explore two innovations designed to prevent future large-scale blackouts while allowing the continued integration of high levels of renewable energy sources. 

The first involves simulating the electric power grid interconnecting France, Spain, Portugal, and the underwater connection to Africa—all affected during the April 28 event. The team will reconstruct the chain of events, assess vulnerabilities, and explore how cross-border exchanges, particularly between France and Spain, can be better coordinated to prevent voltage collapse. 

The second innovation focuses on developing an adaptive power electronics control system capable of stabilising voltage and frequency during extreme grid disturbances. This mechanism is intended to avoid the premature activation of protection protocols that can inadvertently shut down the entire system. 

Together, these innovations could help prevent widespread blackouts, while supporting the transition to cleaner, decentralised energy. To achieve this, the two co-investigators are rethinking today’s operating and planning practices, and aim to deliver recommendations for policymakers.  

For Portugal, that work now includes INESC-ID, through Pedro Carvalho. As a member of the newly formed Technical Advisory Group for Strengthening the Security and Flexibility of the National Electricity System—set up by Portugal’s Minister for Environment and Energy and expected to soon deliver a public report—he is uniquely positioned to help turn research into action. 

The group’s goal is to reinforce the grid’s resilience against future blackouts. For INESC-ID, this participation also reflects recognition of its expertise in energy systems, increasingly called upon in both research and policy contexts. 

The project won’t just be academic. Using MIT’s Power Digital Twin to simulate real-world situations—recently deployed in Puerto Rico to prepare its power grid for hurricanes—the team will better understand the vulnerabilities of the Iberian grid and identify improvements, all while maintaining high use of renewables. 

What adds further urgency and relevance to this research is the current political context. Although the blackout has disappeared from media headlines, “behind the scenes, utilities, especially in Spain, are still under tremendous pressure. Many companies are demanding millions in compensation,” Carvalho explains. 

But practical changes are already underway. In the future, insights from this project could be applied to other regions with high renewable penetration, such as Texas, California, and Northern Europe, and provide recommendations to help industry and governments design better mitigation strategies. 

In the immediate aftermath of the event, uncertainty and lack of information sparked speculation ranging from technical failure to fears of a Europe-wide cyberattack. We were bluntly reminded that our increasingly decentralised and interconnected critical infrastructures are not just technical, they are a societal nervous system.


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Text by Rodrigo Abril de Abreu | Communications and Outreach Office, INESC-ID
© 2025 INESC-ID. Credit INESC-ID and the author, with a link to the original source, when sharing or adapting this article.