6 Days After Celebrating ‘100% Renewable Power’, Spain Blames “Rare Atmospheric Phenomenon” For Nation’s Largest Blackout In History

Six days ago, the media celebrated a significant milestone: Spain’s national grid operated entirely on renewable energy for the first time during a weekday.

At 12:35 pm today local time, the lights went out across Spain and Portugal, and parts of France.

⚡ MASSIVE BLACKOUT IN EUROPE

Residents in Spain, Portugal, France, and Belgium report major outages.
Airports and subways shut down, communication networks hit.
Madrid’s Barajas Airport is out of service, El Mundo reports.
No official cause confirmed yet. Chaos unfolds. pic.twitter.com/vZyJOjhEwj

— NEXTA (@nexta_tv) April 28, 2025

As Michael Shellenberger writes at PUBLIC, this wasn’t just a Spanish blackout. It shook the entire European grid.

…none of this should have been a surprise. The underlying physics had been understood for years, and the specific vulnerabilities had been spelled out repeatedly in technical warnings that policymakers ignored.

…

As countries replaced heavy, spinning plants with lightweight, inverter-based generation, the grid became faster, lighter, and far more sensitive to disruptions. That basic physical reality was spelled out in public warnings as far back as 2017.

…

Although political leaders promised that renewable energy would provide stable, affordable power, in practice, Spain grew more reliant on the remaining nuclear and natural gas plants to sustain inertia — even as the government pushes them to close.

…

Despite all these warnings, political and regulatory energy in Europe remained focused on accelerating renewable deployment, not upgrading the grid’s basic stability. In Spain, solar generation continued to climb rapidly through 2023 and early 2024. 

Coal plants closed. Nuclear units retired. 

On many spring days by 2025, Spain’s midday solar generation exceeded its total afternoon demand, leading to frequent negative electricity prices.

The system was being pushed to the limit.

And today, at 12:35 pm, it broke.

…

Spain’s blackout wasn’t just a technical failure. It was a political and strategic failure.

…

Unless Spain rapidly invests in synthetic inertia, maintains and expands its nuclear fleet, or adds some other new form of heavy rotating generation, the risk of future blackouts will only grow worse.

Read Michael Shellenberger’s full take here…

Crucially, comprehending problem of inertia (or lack of it) is key to apportioning blame for this farce in a major western nation in the 21st century. Mark Nelson (@EnergyBants) simplifies the concept with the following useful metaphor:

The Small or medium-sized disturbances on the grid become very difficult to manage and can cascade into wider instability and outages when the grid is in a low inertia condition, as was the case Monday in Spain just before the massive ongoing blackout

*  *  *

Update (1126ET): Portugal’s grid operator, REN (Rede Eléctrica Nacional), claimed that the massive power outage affecting Portugal and Spain was sparked by a “rare atmospheric phenomenon,” specifically “extreme temperature variations” in the Spanish electricity grid. 

British media outlet LBC News provided more color on REN’s claim:

Due to these variations in the interior or Spain, there were “anomalous oscillations in the very high voltage lines (400 KV), which is a phenomenon known as ‘induced atmospheric vibration'”.

This is such a fascinating graph. A frequency drop of 0.15Hz was enough to take down Spain and Portugal. pic.twitter.com/tZ1OrITtMU

— andi (e/alb) (@Nexuist) April 28, 2025

“These oscillations caused synchronisation failures between the electrical systems, leading to successive disturbances across the interconnected European network.”

. . .

REN added that normalisation of the system could take up to a week.

Bloomberg’s Javier Blas noted:

Before the outage hit, Spain was running its grid with very little dispatchable spinning generation, and therefore no much inertia.

Solar PV/thermal + wind: ~78%
Nuclear: 11.5%
Co-generation: 5%
Gas-fired: ~3% (less than 1GW)

Snapshot at 12.30pm local time (outage was 12.35pm) pic.twitter.com/fF7FiIB6UD

— Javier Blas (@JavierBlas) April 28, 2025

And this:

It’s a race against the sunset to restore power in Spain.

In about four hours, Spain will lose ~1/3 of its current electricity generation (sunset is ~9pm Madrid time).

Spanish national grid is trying to reactivate (black start) as much spinning generation before that.

— Javier Blas (@JavierBlas) April 28, 2025

Additional BBC News headlines of the chaos unfolding across Europe’s Iberian Peninsula:

• Delays at Spanish and Portuguese airports

• In London, Gatwick reports delayed flights to affected areas

• Portugal blames outage on ‘fault in Spain’s electricity grid’

• ‘Extreme temperature variations in Spain’ contributed to outage – Portuguese grid officials

• Restoring power across Portugal ‘could take up to a week‘

• No indications of any cyber attack, says European Council president

• Power back on in some substations, says Spain’s electric operator, but railways still suspended

• French operator supplying electricity to Spain

• Grid operator says power returning in parts of Iberian peninsula

Disruptions…

BREAKING 🚨: Spain, Portugal and a few other EU countries are in total blackout.

Train passengers in Spain got stuck in the middle of nowhere. This is insane.

(This video is from a friend of mine) pic.twitter.com/i7FObGPngS

— Solana Sensei (@SolanaSensei) April 28, 2025

Portugal’s grid operator claims the blackout that shut down much of Portugal, Spain and France today was caused by Spain’s electricity grid malfunctioning “due to a rare atmospheric phenomenon” pic.twitter.com/IzY1MFhF9n

— Visegrád 24 (@visegrad24) April 28, 2025

“I’m in Spain and trust me the issue isn’t the darkness…No payments possibles without cash (so no food and transportation), very limited internet and no clue whether it’ll actually be resolved,” one X user told Javier. 

I’m in Spain and trust me the issue isn’t the darkness…No payments possibles without cash (so no food and transportation), very limited internet and no clue whether it’ll actually be resolved..

— Jordan B (@JayStew21721754) April 28, 2025

The blackout highlights just how fragile the new digital and “green” society has become.

*   *   * 

Large swaths of Spain and Portugal plunged into darkness on Monday. 

Spanish power grid operator Red Electrica wrote on X:

• Plans activated to restore electricity supply in collaboration with sector companies following the blackout that occurred in the peninsular system.

• The causes are being analyzed, and all resources are being dedicated to resolving it.

“Parts of France also appear to be affected, according to Spanish media reports, which said Seville, Barcelona and Valencia were hit by the outage,” SKY News reported.

Bloomberg’s Javier Blas called the power outage “Massive — really, massive.” 

“Massive — really, massive — electricity outage hits Spain, which large part of the country suffering blackouts (including Madrid and Barcelona). Data from Spain’s national grid shows a lost of >10 GW of demand, from ~26GW to ~12GW in a few seconds. Reason unknonw.”

BREAKING: Massive — really, massive — electricity outage hits Spain, which large part of the country suffering blackouts (including Madrid and Barcelona).

Data from Spain’s national grid shows a lost of >10 GW of demand, from ~26GW to ~12GW in a few seconds. Reason unknonw. pic.twitter.com/KwvDxOOLQJ

— Javier Blas (@JavierBlas) April 28, 2025

Cloudflare reported that internet connectivity dropped “by as much as 30% in Portugal and 37% in Spain” due to the power outages. 

Ongoing nationwide power outages in Portugal and Spain are impacting Internet traffic. Traffic dropped by as much as 30% in Portugal and 37% in Spain at 10:30 UTC. We are continuing to monitor the situation. pic.twitter.com/7yD2V48Ybj

— Cloudflare Radar (@CloudflareRadar) April 28, 2025

Outages have begun to affect air travel. 

Diversions have begun #power #spain #portugal #electricity #bcn pic.twitter.com/csIg2WIqYQ

— Alex Krstanovic (@acabgd) April 28, 2025

Footage:

Major power outage across parts of France, Spain and Portugal.

Causing some chaos at the Madrid Open.

Fans streaming for the practice courts (which have now hit capacity), food stalls operating with torches and cash, portions of the venue in complete darkness. pic.twitter.com/4B1NAPX13A

— Connor Joyce (@connorjoyceb) April 28, 2025

Total power outage across Spain and Portugal. Currently waiting for a train and all trains suspended. pic.twitter.com/tF9Feo1lRr

— Crypto Trader Simon (@cryptotrader_si) April 28, 2025

is this what caused the spain and portugal power outage? #spain #Portugal #power #poweroutage pic.twitter.com/IVXiZfX1NS

— Josh2809 (@Josh28091) April 28, 2025

Red Electrica provided no details about what caused the nationwide blackout. 

How long until Brussels blames the Russians? 

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