Il y a eu un complément d'informations publié sur le site de l'enquête de l'entso-e, l'organisme européen de supervision du réseau, mais le moins que l'on puisse dire c'est que l'on n'y apprend pas grand chose de plus.
Il y a par exemple des précisions supplémentaires sur les trois événements de délestage, ayant entrainé une perte totale de 2200W d'énergie produite, sur des installations EnR, mais non nommées précisément, mais le site indique que la raison de ces délestages, qui sont pourtant la cause finale de l'effondrement du réseau, sont toujours en cous d'investigation.
Il est prévu une conférence de presse demain, pour présenter les résultats préliminaires de l'enquête, mais je ne sais pas ce qu'ils vont pouvoir dire de plus...
La conclusion est que c'est un événement atypique, et qu'il faut renforcer la résilience du réseau. Oui, mais encore ?
Pour rappel : Tripping = délestage en français.
On a donc à 12:32:57, le délestage d'un transformateur du côté de Grenade, qui reliait des centrales PV, éoliennes et thermo-solaires, pour 355W, puis à 12:33:16 le délestage de centrales PV et thermo-solaires reliées à une sous-station de 400 kV dans la région de Badajoz (frontière Portugal), pour 720 MW, puis à 12:33:17, une seconde plus tard, une série de délestages de centrales PV, thermo-solaires et éoliennes toujours dans le sud, pour 1100 MW. Et donc pour l'instant pour des raisons inconnues...
At 12:32:57, 12:33:16 and 12:33:17 CEST
Loss of generation was observed in the regions of Granada, Badajoz and Sevilla, accounting to an initially estimated total of 2200 MW.
The first event was due to the tripping of a generation transformer, due to a problem in the lower voltage side, in the area of Granada, which connected different generation facilities (photovoltaic, wind and thermo-solar) to the transmission grid and which was injecting 355 MW. The tripping of the transformer and consequently the loss of infeed options also explains the disconnections of some of the generation units connected to this transformer due to over-frequency while others trip due to overvoltage, as reported by the operators of the power plants.
The second event included trips of PV and thermo-solar facilities connected to two transmission 400 kV substations, in the area of Badajoz, with a total interrupted injection of around 720 MW.
The third event included several trips, in different areas, in less than one second: wind farms in Segovia and Huelva, photovoltaic in Badajoz, Sevilla, Caceres and Huelva and thermo-solar in Badajoz, and other generators in different locations for a total of more than 1100 MW, as confirmed by the variation of frequency.
The causes of these three events are still under further investigation.
No generation trips were observed in Portugal and France within this timeframe. As a result of these events a voltage increase was observed in Spain, leading to a similar increase in Portugal, while the frequency decreased.
...
On the basis of the preliminary facts established to date, the Expert Panel is currently looking at the cascading series of generation disconnections and voltage increases (‘cascading voltage increases’) as the most probable trigger for the blackout. Such cascading voltage increases have never before been linked to a blackout in any part of the European power system. If confirmed, this high voltage blackout mode will require a thorough analysis and investigation by all power system experts of the ENTSO-E community.
The exceptional character of this incident highlights the need to improve the resilience the power system in such situations. ENTSO-E sees at least two important lines to consider:
- enhancing voltage control management procedures and capabilities of all active actors of the electricity system to prevent such major voltage-related incidents in the future;
- assessing how the system defense plans can better protect the European power system against this new type of phenomena.
https://www.entsoe.eu/publications/blackout/28-april-2025-iberian-blackout/
Énergie