ACER amends day-ahead and long-term capacity calculation methodologies for the Core electricity capacity calculation region
Risk profileHIGH — ACER binding decisions amending capacity calculation methodologies carry immediate compliance obligations for transmission system operators across fifteen EU member states and alter the technical framework governing cross-border electricity capacity for all Core CCR market participants.
ACER has adopted two decisions amending the day-ahead and long-term capacity calculation methodologies for the Core capacity calculation region. The decisions update the technical framework governing cross-border electricity capacity allocation across the Core CCR, which spans fifteen EU member states.
- Binding Methodology Changes for Core CCR Transmission System Operators. Transmission system operators within the Core capacity calculation region must implement the amended day-ahead and long-term flow-based methodologies. These operators carry direct compliance obligations under the revised decisions, requiring updates to capacity calculation processes and coordinated operational procedures.
- Long-Term Flow-Based Calculation Now Formally Embedded. The amendments extend flow-based capacity calculation into the long-term timeframe, moving beyond the day-ahead application that has been the operational standard in Core. Market participants using long-term transmission rights in the Core CCR face a changed technical basis for capacity availability assessments.
- Cross-Border Electricity Trading Conditions Affected. Energy traders, power exchanges, and nominated electricity market operators active in Core CCR markets operate under capacity figures derived from the amended methodologies. Changes to the calculation framework alter the volume and distribution of available cross-border capacity offered to the market.
- Coordinated Implementation Required Across Fifteen Member States. The Core CCR covers Austria, Belgium, Croatia, Czech Republic, France, Germany, Hungary, Luxembourg, the Netherlands, Poland, Romania, Slovakia, Slovenia, and two further members. Coordinated implementation across national regulatory authorities and TSOs in this footprint introduces execution complexity with no single-jurisdiction fallback.
Bottom lineThe two ACER decisions bind transmission system operators across the Core CCR to amended capacity calculation methodologies for both the day-ahead and long-term timeframes. The long-term extension of flow-based calculation is the structural change: it aligns the long-term horizon with the day-ahead framework already in place and alters the technical basis on which cross-border capacity is determined and offered. Market participants holding or acquiring long-term transmission rights in the Core CCR operate under a revised capacity calculation foundation as of these decisions.
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