Dimensioning of balancing services requirement
Determining the need for FCR
The amount of Frequency Containment Reserve (FCR) to be maintained by the German TSOs is determined annually in coordination with the continental European transmission system operators (TSOs).
According to Article 153(2) SO GL, the total amount of FCR to be maintained in the continental European interconnected system is derived from the ±3,000 MW reference disturbance or a probabilistic dimensioning. The probabilistic dimensioning takes into account various influencing factors to ensure that the available FCR is statistically insufficient only once every 20 years.
The allocation within the continental European interconnected system is based on the ratio of the annual feed-in and load of the individual TSOs.
Details can be found in Annex 1 of the Synchronous Area Framework Agreement for Regional Group Continental Europe, which is published on the Entso-E Transparency Platform.
Determining the need for aFRR and mFRR
The aFRR and mFRR to be maintained are collectively dimensioned by all four German TSOs for the allocated volume to the German grid. A probabilistic approach is used, which takes into account the probability of imbalances in the respective dimensioning period. The result corresponds to the dimensioning for the German Grid Control Cooperation (GCC).
Starting from December 9, 2019 (for the delivery day December 10, 2019), the dimensioning is no longer carried out quarterly for the following quarter, but individually for each 4-hour product. The basis for this is the historical system imbalances. Power plant outages are subtracted from this basis and considered through a failure probability of the power plant fleet. The foundation is the statistical failure probability of the individual types of power plants. All power plants with a capacity of 100 MW or more are considered. The input data classification takes into account the following parameters:
- Time of day
- Date
- Month
- Day of week
- Type of day (holiday, bridging day, or days with special events)
Details of the dimensioning process can be found in the report on dynamic dimensioning. The dynamic dimensioning results in volatile requirements between consecutive time periods or days. The TSOs have gradually introduced the process to give all market participants sufficient time to adapt. The dimensioning process has been fully implemented since October 3, 2020 (delivery day).