Iberian Blackout – The Fight Begins

Renewable energy had nothing to do with Spain’s catastrophic blackouts, its Prime Minister says, insisting instead that the real culprit was a rare technical failure unrelated to the country’s green energy transition. Prime Minister Pedro Sánchez went further and reiterated his government’s opposition to nuclear energy, which he called “far from being a solution.”

But, as I pointed out on Monday, the underlying cause of the blackout was the lack of “inertia,” the physical buffer provided by traditional power plants that use heavy spinning machinery to stabilize the grid during sudden fluctuations. Our electrical systems are based on power plants that rotate massive metal shafts at thousands of revolutions per minute, creating electricity while also providing momentum. That rotational mass acts like a shock absorber, automatically resisting sharp swings in supply and demand. When a fault or sudden drop hits the system, that inertia buys precious seconds for control systems to respond and for operators to isolate the problem. In contrast, solar panels and most modern wind turbines rely on inverters, which lack physical mass and can’t cushion these shocks.

It’s true that the electrical grid managers have not identified a specific cause that triggered the blackout, and both Spain’s Red Eléctrica and Portugal’s REN have cautioned that a full root-cause analysis may take weeks. Preliminary reports describe a “very strong oscillation” in the network and suggest the event began with an unexpected disturbance, possibly linked to a sudden drop in generation or an equipment fault.

But that doesn’t change the fact that the Spanish grid lacks inertia, and that if it had had more inertia in the system the blackout could have been avoided or at least contained. Inertia is not a theoretical nicety, it’s a physical property provided by heavy, spinning generators like those in gas, coal, and nuclear plants, which naturally resist sudden changes in frequency. On the day of the blackout, nearly 80 percent of Spain’s electricity came from inverter-based solar and wind sources, which provide no such stabilizing force. With so few conventional plants online, the grid had virtually no buffer to absorb even a minor shock. When the disturbance hit, the frequency plunged and the system unraveled within seconds. Unlike older grids built around rotating mass, Spain’s modern, ultra-light grid simply had no way to withstand the sudden imbalance.

And Spain’s electrical grid operator admitted on a conference call yesterday that it was a “massive” loss of renewable energy generation that triggered the blackout and said that it was “very likely” the initial disturbance came from solar.

In a briefing with reporters, Red Eléctrica de España outlined a sequence of failures beginning at precisely 12:33 p.m., when the grid suffered what it described as an “event akin to a loss of generation” in the country’s southwest—most likely from solar. Although the grid initially self-corrected, it was hit again just 1.5 seconds later by a second shock, also “akin to another loss of generation,” which further destabilized the system. Seconds after that, the Iberian grid broke from the rest of Europe, and within moments, a “massive” drop in renewable power output plunged Spain’s generation to zero.

In truth, nobody should be shocked by what happened in Spain, since many people, including I, have been warning about it for years, and the International Energy Agency even warned of this very thing just a few days ago in a conference and a confidential report which it has not made public. According to Bloomberg, the IEA’s unreleased paper stated plainly that “systemic challenges will emerge from balancing increasingly renewable-dominated grids during extended low-generation periods,” an admission that the weather-dependent nature of solar and wind cannot sustain round-the-clock demand without serious consequences.

The report also warned that current vulnerabilities stem from the “premature retirement of dispatchable generation without adequate replacements,” singling out countries like Germany that have closed their nuclear fleets without securing grid stability. And while policymakers in Madrid have long ignored these structural risks, even Spain’s own grid operator admitted in a February report, two months before the blackout, that the system was dangerously exposed: the high share of renewables, it said, lacked the technical capabilities to ride out disturbances, making severe outages more likely. Specifically, it mentioned the potential for “generation disconnections” during periods of high renewable output, which could compromise grid stability and increase the likelihood of severe outages.

These challenges are coming at a time when artificial intelligence is expected to drive a huge spike in electricity use, putting even more pressure on already fragile power grids. The International Energy Agency says that by 2030, data centers could use more electricity each year than the entire country of Japan, with AI being the most important driver of that growth. In the U.S., AI is the most important driver of rising electricity demand from data centers, and AI services and the infrastructure around them are projected to account for nearly half of all new electricity demand over the next five years, outpacing even heavy industries like steel and cement.

In Europe, experts expect data centers to use nearly twice as much electricity in 2030 as they do today, eventually reaching five percent of total demand, roughly equivalent to all the power currently used by the entire country of Belgium, due in large measure to the use of AI. And globally, the electricity needed just to keep AI systems running could double in the next five years.

The costs of changing the electrical grid so it relies on weather-dependent renewables would be enormous, and Germany is a cautionary tale. After shutting down its last nuclear power plants and losing access to cheap Russian natural gas, Germany’s energy prices soared, and its economy entered a prolonged slump. The country has now spent hundreds of billions of euros on its energy transition, yet it still burns coal during peak demand and struggles to keep industry competitive. Manufacturing output has fallen, major chemical and steel producers have cut back or relocated, and high electricity costs have made new investment increasingly unattractive.

Despite the promises of clean, affordable energy, Germany pays the most for electricity in Europe. Meanwhile, the shutdown of dispatchable power sources like nuclear and gas has left its grid more vulnerable to fluctuations and forced reliance on emergency imports from neighboring countries when the sun doesn’t shine or the wind doesn’t blow. And German ratepayers will have to pay another $490 billion to expand its electrical grid by 2045 to deal with all the weather-dependent renewables.

As such, Sánchez and other European leaders are being dishonest about the causes of the blackouts and about the essential role of nuclear power. By insisting that the outage had nothing to do with renewables and doubling down on the shutdown of dispatchable, low-carbon nuclear plants, they are ignoring both the physical realities of grid stability and the warnings from their own experts. Nuclear power provides the kind of steady, inertia-rich generation that stabilizes the grid and keeps the lights on when renewables dip. Yet Sánchez used the blackout as an opportunity to again attack nuclear energy, even as solar output collapsed and the remaining nuclear plants helped prop up the grid.

In fact, Sánchez and his allies are actively trying to shut down Spain’s nuclear plants, even as those reactors provide the country’s most reliable and emissions-free source of baseload electricity. Under the government’s current energy plan, all remaining nuclear power stations are scheduled to be phased out by 2035, a decision rooted more in ideology than in engineering. This is happening at the very moment when the grid is becoming more fragile, demand is rising due to electrification and AI, and gas prices remain volatile.

As such, Sánchez is spreading misinformation—and perhaps even disinformation—about the causes of the blackout and the role of nuclear energy, all while pushing for stricter government and EU-wide censorship of dissenting views on social media. The Sanchez administration and allies in Brussels have supported legislation that pressures platforms to remove or suppress content that questions the green energy transition, nuclear plant closures, or official energy narratives.

Even more alarming is that Sánchez has demanded that every European be forced to adopt a “digital ID” system—one that privacy experts warn could be used to track, monitor, and even punish people for what they say online. As Cecílie Jílková reported in February for Public, Sánchez used his speech at the World Economic Forum to call for “an end to anonymity on social media” and insisted that “all these platforms” should be required to “link every user account to a European Digital Identity Wallet.” This app would combine citizens’ bank accounts, health records, tax filings, and personal documents in a single system that governments—or companies managing the platform—could potentially use to monitor behavior and enforce speech restrictions.

Why is Sánchez doing this? Money is likely a big part of it. He and his party, the Spanish Socialist Workers’ Party (PSOE), have cultivated close ties with major renewable energy companies and investment funds that stand to profit enormously from Spain’s green energy push. Spain is one of the most aggressively subsidized solar and wind markets in Europe, and the country has committed billions of euros, much of it from the European Union’s green recovery funds, to renewable projects backed by politically connected firms. Major Spanish utility companies like Iberdrola and Acciona, which have deep stakes in wind and solar, benefit directly from favorable regulatory treatment and guaranteed above-market rates for green energy. Last year the Spanish government announced another $18 billion in subsidies for renewable plants.

This is not an issue that should only worry Spaniards, given how close the Spanish blackout came to causing blackouts across all of Europe. The Iberian Peninsula’s grid, though geographically semi-isolated, is still synchronized with the continental European system, and when Spain’s frequency plummeted on April 28, grid monitors registered destabilizing ripples throughout the broader network. Had the separation not occurred when it did, the entire interconnected European grid—stretching from Portugal to Poland—could have been exposed to the same cascading failure. Frequency stability is not a national concern; it’s continental.

As more countries follow Spain’s lead in phasing out nuclear and dispatchable power while relying heavily on inverter-based renewables, the risk of continent-wide instability grows. Germany, France, and Italy may soon find that their own grids, once considered robust, are only as strong as their weakest neighbors. In this sense, Sánchez’s policy choices and his refusal to confront their consequences are not just a domestic failure, they are also a European vulnerability.