Spanish Power Outage - The Official Report

[Crossy]

 

 

https://euroweeklynews.com/2025/06/18/spains-blackout-cause-finally-revealed/

 

 

The report itself https://d1n1o4zeyfu21r.cloudfront.net/WEB_Incident_ 28A_SpanishPeninsularElectricalSystem_18june25.pdf

From here https://www.ree.es/en/operation

 

Interestingly: - 

"The incident was NOT caused by a lack of system inertia. Rather, it was triggered by a voltage issue and the cascading disconnection of renewable generation plants, as previously indicated. Higher inertia would have only resulted in a slightly slower frequency decline. However, due to the massive generation loss caused by voltage instability, the system would still have been unrecoverable."

 

The TL;DR sequence of events is summarised in the report as follows: -

 

(Note: The generation that must comply with P.O. 7.4 regulates, in a mandatory way, voltage dynamically and independently of the active power they are generating, thus it ensures stable voltages in the network.

and

RCW = Renewable, Cogeneration, and Waste)

1. Forced oscillation at 0.6 Hz, possibly originating in a photovoltaic power plant in the province of Badajoz,triggers system-altering protocolized actions. Shunt reactors are operated, lines are coupled due to oscillations, and schedules are modified. (N-1)

2. Natural oscillation at 0.2 Hz triggers further system-altering protocolized actions. Shunt reactors are operated, lines are coupled due to oscillations, and schedules are adjusted. (N-2).

3. Generation under P.O. 7.4 does not absorb the required reactive power. (N-3).

4. Variations in RCW generation during active power regulation affect voltage control and many of them don't fulfil their obligations. (N-4).

5. The conventional generation requested after the oscillations was not connected.

6. Generation loss in distribution: P < 1 MW and self-consumption of 435 MW before 12:32:57 (N-5).

7. Inappropriate tripping of a generation transformer in Granada (N-6).

8. Inappropriate tripping of solar thermal generation (Badajoz) and tripping of photovoltaic (Badajoz) withoutpoint-of-interconnection data from transmission network (N-7).

9. Inappropriate tripping of a photovoltaic power plant connected also in the province of Badajoz but in a different transmission substation (N-8).

10. Tripping of three wind farms (Segovia) without point-of-interconnection data from transmission network.

11. Tripping of one wind farm and a PV plant located at the province of Huelva, without point-of-interconnection data from transmission network.

12. Inappropriate tripping of photovoltaic power plant in Seville (N-9).

13. Inappropriate tripping a PV generation located in the province of Cáceres (N-10).

14. Tripping of PV generation connected to a 220 kV substation located in the province of Badajoz, withoutpoint-of-interconnection data from transmission network.

15. Tripping of one CCGT unit located at Valencia (N-11).

16. Load shedding of pumping units and loads due to underfrequency results in increased system voltage.

17. The HVDC link operating in constant power mode continues exporting 1,000 MW to France.

18. Tripping of Nuclear Power Plant. (N-12)