The DE-AT-PL-4M MC (also known as the ‘Interim Coupling’ or ‘ICP’) was a day-ahead market coupling project based on the Net Transmission Capacity (NTC) method which coupled the borders between two formerly running day-ahead market coupling projects 4M Market Coupling (‘4M MC’) and Multi-Regional Coupling (‘MRC’). The two regions had operated separately until June 2021, when the borders between Czech Republic, Hungary, Germany, Poland, Austria and Slovakia were coupled.

This transition towards implicit capacity allocation represents a major step towards the timely achievement of the Single Day-Ahead Coupling (‘SDAC’) in the EU even before the introduction of the target Flow-Based method, as set out in the Commission Regulation 2015/1222 establishing a guideline on capacity allocation and congestion management (CACM Regulation).

The implementation of ICP lasted 27 months and included – apart from OTE – 15 project parties from Poland, Germany, Austria, Slovakia, Hungary and Romania. The project was successfully launched on June 17, 2021, and SDAC has thus transitioned into its final Enduring Phase. SDAC now consists of 47 parties from almost all EU Member States and Norway.

NTC Capacity Calculation Method 

The NTC method represents a calculation of transmission capacity based on the maximum amount of electricity that can be transferred between the bidding zones without compromising the security of both systems and respecting some technical uncertainties regarding future network conditions. These physical transmission constraints need to be transformed into business constraints called Net Transmission Capacity (‘NTC’).

Picture 4 – Market Coupling: Timeline

The benefits of the ICP project are following:

• generates social welfare (thanks to the fact that implicit allocation means that the buying or selling of electricity and the transmission capacity are allocated at the same time),
• increases the liquidity of daily cross-border trading,
• provides valuable experience for both project parties and market participants,
• some aspects of the ICP project may be partially or fully incorporated in the Core FB MC project, which will facilitate its implementation,
• may have a positive impact on the enlargement of SDAC.