2025-05-01 , updated 2025-05-01
Day 3 of the European Power Outage 2025 scenario
Written by: Robert
Keywords: power-grid, civil-protection, readyness
Network Instability Before the Incident
Several sources have reported network instability or fluctuations in the days and hours before the incident that occurred on April 28.
Bob Marshall, CEO of Whisker Labs, described small voltage fluctuations starting around 9:30 a.m. local time in Madrid, detected by a couple dozen sensors in homes around the area. These sensors, primarily used for home fire prevention and grid monitoring, showed oscillations in voltage that increased in frequency and magnitude over three hours until the grid failed. By noon, the fluctuations reportedly spiked, with voltage varying by about 15 volts every 1.5 seconds, indicating significant grid instability.
However, there are no publicly available sensor output graphs or specific data from Whisker Labs detailing the voltage fluctuations Marshall referenced regarding the power outage in Spain on April 28, 2025.
No detailed datasets, graphs, or raw sensor outputs have been released or cited in available sources, including Whisker Labs’ own site or media reports. The Whisker Labs Ting Sensor Network page mentions monitoring grid resilience but does not provide specific data or visualizations for this event. Without direct access to Whisker Labs’ proprietary data, it is not possible to independently verify or visualize the described fluctuations.
Official Responses from the Primary Power Grid Operator
There have also been additional official responses from the president of the Red Eléctrica company.
On April 30, Red Eléctrica’s president, Beatriz Corredor, addressed multiple questions that had been raised in the days after the April 28 outage incident.
On finding the cause, she stated:
We know the cause and we have it more or less tracked down, but the thing is there are millions of pieces of information because signals are sent every millisecond,
On cyberattack as a possible cause, and on the data collection process, she stated:
There is absolute transparency in this data collection. Regarding the conflicting versions with the government about whether it could have been a cyberattack, she maintained that her indications indicate that this did not happen.
There has been speculation about whether the reliance on renewable power production installations could have contributed to the incident. She implied that the configuration of the various sources, like nuclear, solar, and hydro power, is reliable:
Regarding the ongoing debate about what could have gone wrong, and whether renewables may have had anything to do with it, Corredor emphasized that we have a very reliable mix, but she also declined to go into technical details.
Electromagnetic Resonant Oscillation Influences on the Power Grid
Some sources online have published spectrograms of the Schumann resonance from the day of the blackout and claim that the peaks in these diagrams coincide with the time of the outage.
The Schumann resonance consists of naturally occurring electromagnetic standing oscillations in the cavity between the conducting ionosphere and the Earth. They are generated by lightning around the globe and propagate around the Earth. The low frequencies of the oscillations range between 3 Hz and 30 Hz (although spectrograms from April 28 do show increased power beyond 30 Hz). The frequency varies with the time of year and climate conditions, and depends on the precise altitude of the ionosphere (a parameter of the resonant standing wave) and the amplitude or power of global thunderstorm activity.
Schumann resonances are of interest to atmospheric scientists because they indicate lightning activity, which is often influenced by global temperatures and instabilities in the lower troposphere.
However, it is important to emphasize that there is no evidence that Schumann resonances could affect power grids. There is also an abundance of false information and myths online about this phenomenon.
Although Schumann resonance is a very interesting phenomenon to study, no convincing explanations have been given as to how these naturally occurring phenomena could be related to power grids. Thus, we will not publish the spectrograms here.
Final Note
As also mentioned in the previous note, there is an element of investigative sensitivity: With the Spanish authorities still probing potential causes, including terrorism, data may be withheld to avoid speculation or interference.
Additionally, certain third-party sensor data products may be proprietary and thus not available to the public.
In summary, while we wait for official data to be released or approved, investigations to conclude—and after ruling out Schumann resonance as a possible cause (for now)—we must rely on indications from consumer-grade systems such as Whisker Labs.