Somebody with decent chops has produced some excellent digests of events leading to similar, on Wikipedia. ( went down this rabbit hole quite recently)

#GridCollapse
#PowerTransmission
#ElectricalGrid

https://arstechnica.com/tech-policy/2025/04/massive-power-outage-in-spain-portugal-leaves-millions-in-dark/

Massive power outage in Spain, Portugal leaves millions in dark

Cause likely not malicious; Red Electrica blames outage on “grid oscillation.”…

Ars Technica