In July 2025, electricity transmission system operators (TSOs) submitted to ACER their proposal to amend how capacity calculation regions (CCRs) are defined across Europe.
With its Decision 10-2025, ACER has approved the proposed amendments.
What are capacity calculation regions and why are they important?
CCRs are geographic areas across Europe that group neighbouring electricity bidding zones and their borders. Within each region, TSOs work together to determine how much electricity can safely flow across borders while ensuring security of supply.
There are currently nine CCRs in the EU: Nordic, Hansa, Core, Italy North, Central Europe (CE), Greece-Italy (GRIT), South-West Europe (SWE), Baltic and South-East Europe (SEE). They are key to improving regional coordination, ensuring efficient electricity use and facilitating cross-border trade.
What did ACER decide?
ACER assessed whether the TSOs’ proposal supports market integration, non-discrimination, effective competition and the well-functioning of the EU electricity market.
Following a public consultation in summer 2025, ACER has approved the TSOs’ proposal to:
- Merge two existing CCRs (Core and Italy North) into the Central Europe CCR for key regional processes like intraday coordination and congestion management.
- Expand the existing South-East Europe CCR and establish three new CCRs (East-Central Europe, Italy-Montenegro and Eastern Europe) to include the bidding zone borders and TSOs of the Energy Community Contracting Parties and neighbouring EU countries.
