The flow-based coupling method
Flow-based coupling within the Central West Europe, region including France, Belgium, Germany, Luxembourg and the Netherlands within which electricity market prices have been coupled since 2010 region went live on 21 May 2015.
Prior to that, these four bidding zones were coupled on a Net Transfer Capacities (Net Transfer Capacity, the transfer capacity made available to the market for imports and exports, calculated and published jointly by the system operators. Transfer capacity depends on the characteristics and availability of interconnection lines and internal constraints on individual countries’ power grids) basis, meaning that limitations on exchanges were set bilaterally for each border (one constraint per border and per direction, implicitly taking into account the state of the network).
Constraints now explicitly take into account the physical network infrastructure in the five countries. Cross-border exchanges are thus optimised to reflect the actual physical capacities of networks as accurately as possible. This requires very close coordination between transmission system operators in Central West Europe, region including France, Belgium, Germany, Luxembourg and the Netherlands within which electricity market prices have been coupled since 2010 countries.
In sum, it is no longer possible to consider borders separately, and indicators previously used for the France-Belgium and France-Germany borders have been replaced by France-CWE region indicators