The Belgian grid is part of an interconnected system stretching from Portugal to Poland.

Interconnection capacity

Available border transmission capacity is mainly determined by:

  • the topology of the European grid (i.e. components in service and how they are interconnected) ;
  • exchanges between countries;
  • periods of unavailability on the 380/220 kV grid (unavailability of transmission lines, phase-shifting transformers or major generation units) in Belgium or in a neighbouring country. 

Belgium's central position in the European transmission system means it has to cope with significant unscheduled physical flows (i.e. energy exchanges which are not governed by a commercial agreement between countries, but are simply due to the fact that energy moves freely through the grid without stopping at borders). Such flows are a major source of uncertainty for Elia when calculating the amount of energy that can be exchanged with neighbouring countries.  

Visit Transmission capacity at borders for more information on Elia’s capacity calculation methods.


Capacity allocation mechanisms

Elia has introduced interconnection capacity allocation mechanisms for transnational energy exchanges. These mechanisms satisfy market demand in a transparent and non-discriminatory manner.

Information concerning methodology changes and operational situations considered as inside information related to these allocation mechanisms (and more specifically flow-based market coupling and intraday available transfer capacity [ATC] after flow-based market coupling) can be found on the Joint Allocation Office’s website (JAO).

Annual and monthly capacity 

Joint auction rules for the allocation of capacity across borders within the CWE (Central West Europe) region were implemented on 1 November 2009, as agreed between the seven transmission system operators active in the CWE region. The auctions are organised by JAO.EU, an auction office. Auctions are organised to allocate annual and monthly capacity across Belgium’s borders.

Daily capacity

The implicit allocation of daily capacity through market coupling was expanded to include the CWE region on 9 November 2010 (for 10 November 2010), replacing the previous market coupling between France, Belgium and the Netherlands.

Intraday capacity

Since 12 June 2018 (for 13 June 2018), intraday capacity has been implicitly allocated uniformly across all borders using the XBID platform. This new allocation method has replaced the previous implicit mechanisms.

To learn more about previous mechanisms, visit Cross-border mechanisms.


Operational data

Visit this section’s sub-pages for information on the operational data below:

  • forecasts and capacities available during various timeframes;
  • auction results;
  • nominated capacities;
  • physical flows;
  • deactivated Elia grid components.