[CWE Flowbased Market Coupling] Introduction of the light SPAIC approach

Dear market participants,

CWE TSOs would like to inform you about the introduction of an additional methodology to assess the impact of changes to the Flow Based Capacity Calculation in CWE.

As discussed in the CWE Consultative Group in April and September 2019, CWE TSOs will use the new methodology to improve transparency of the CWE Flow Based Capacity Calculation. Please find attached the slides presented during the last CCG call for your information.

After final alignment with CWE NRAs, and complementary to the well-established full SPAIC, CWE TSOs will apply from today on the new methodology of a light SPAIC for certain trigger criteria.

A light SPAIC will be triggered for

· Expected outages of Critical Network Elements longer than 6 weeks (temporary situation)

· New internal assets directly connected to cross-border lines

· New Critical Network Elements used for capacity calculation

The light SPAIC focuses on the recalculation of flow based parameters for seven business days which will be chosen from a period of one month prior to the SPAIC. The recalculated parameters take into account the change which triggers the SPAIC. The seven days will be representing different grid situations:

· Day 1: Sunday in the available period with the lowest wind infeed in CWE (DE as proxy)

· Day 2: Workday in the available period with the highest wind infeed in CWE (DE as proxy)

· Day 3: Workday or Saturday in the available period with average wind/load

· Day 4-5: Smallest/Largest volume of the Flow Based Domain

· Day 6-7: Lowest/highest exchanges in CWE

Simulation of market results for the seven days will be skipped in case the light SPAIC shows no significant change in capacities and CWE TSOs can exclude significant impact on final Net Positions and Social Welfare.

More details about the full and light SPAIC approaches including the SPAIC processes & related time lines and an explicit list of trigger criteria for each type of a SPAIC will be shared at the end of this month.

Best regards

CWE TSOs