The Market Coupling Steering Committee (MCSC) initiated an in-depth investigation of the partial decoupling of SDAC and cancellation of SIDC IDA3 taking place on 25 of June (trading date)

During the SDAC market coupling process on 25 June, for delivery date of 26 June, some technical issues were experienced that led to a partial decoupling.

• Countries/Bidding zones decoupled from SDAC: Denmark, Estonia, Finland, Latvia, Lithuania, Norway, Sweden.
• Order books decoupled from the SDAC process:
o EMCO – Nord Pool (Nordic CCR & Baltic CCR),
o EPEX SPOT (Nordic CCR & Core CCR).
• Several interconnectors decoupled from the SDAC process.*

Partial decoupling from SDAC
The incident was caused by local issues at EPEX SPOT preventing the order books from EPEX SPOT to be submitted before the operational deadline. It could not be fixed within the time allocated by the SDAC procedures and a partial decoupling was declared at 13.05 CET in line with the relevant procedure. Thanks to the Multi NEMO Arrangements in Core CCR, which allow multiple NEMOs to operate in one same Bidding Zone, cross-zonal capacities in the countries of the Core CCR were successfully implicitly allocated in flow-based between the remaining coupled Core NEMOs and without any reduction of capacities. Due to this fact the organization of shadow auctions within Core CCR borders was not necessary.

The Nordic and Baltic CCRs were decoupled in line with the regional fallback procedures. Therefore, a Nordic-Baltic regional coupling operated by EPEX SPOT and Nord Pool EMCO was triggered, until its successful completion. Additionally, shadow auctions via JAO were successfully conducted for the relevant Hansa CCR borders (see table below).

The robust organization of market coupling ensured market results computation and publication despite major operational challenges. The final SDAC market coupling results for the remaining cou-pled parties were published at 14:09 CET. The common coupling system worked as expected and ensured the coupling of the remaining part of SDAC topology. The SDAC auction of 26.6.2024 (trad-ing day) was run normally, in a fully coupled mode.

SIDC IDA3 cancelled and IDA1/IDA2 successfully executed

At an earlier stage on 25.6.2024, this same local technical issue at EPEX SPOT also led to the cancellation of the SIDC IDA3 at 10:00 CET for delivery date of 25 June. For the avoidance of doubt, the cancellation of IDA3 and above mentioned SDAC partial decoupling were not linked together, apart from having been caused by the same local technical issue.

However, despite the very challenging SDAC events, the DA coupling process timely finalized at 14:09 and therefore the first intraday auction for delivery date of 26 June (SIDC IDA1 at 15:00 CET) was properly executed and TSOs could timely calculate and provide the ID cross-border capacities. Nonetheless, this took place without the Nordic and Baltic CCRs, and without EPEX SPOT order book, as they were partially decoupled in advance due to the ongoing Nordic-Baltic process.

After timely resolution of the issue by EPEX SPOT, the second intraday auction for delivery date of 26 June (SIDC IDA2 at 22:00 CET) was performed again in fully coupled mode.

The MCSC has initiated an in-depth investigation. A decoupling report summarising the outcome of the investigation and potential lessons learned is expected to be published within a month time.

*Interconnectors decoupled from the SDAC process