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Frequency Containment Reserve

Frequency Containment Reserve

The frequency containment reserve (FCR) reacts to frequency changes and must be provided in full within 30 seconds. In addition, the FCR must be provided symmetrically; there is no differentiation between positive and negative FCR. Activation is frequency-dependent, which means that the providers measure the grid frequency independently at the point of generation or consumption and react immediately to the grid frequency change.

The FCR stops the frequency change and stabilizes it, regardless of where in the European interconnected grid the frequency deviation was caused. In order to return the frequency to 50 Hertz and replace the FCR, FRR must be used in the control area that caused the frequency deviation with a balance imbalance. The amount of energy that flows into the control area with the imbalance due to the activation of FCR is included in the unintentional exchange and is settled monthly between the TSOs.

Technical properties

ActivationAutomatic, decentralized based on the grid frequency
Activation period
Complete activation within 30 seconds

Further product features and information on procurement can be found under Procurement of control power.

A large proportion of the FCR required in Germany is provided by battery storage systems, which charge and discharge the battery through the fairly even distribution of overfrequency and underfrequency in order to provide FCR.

The German TSOs procure the FCR in a joint tender with other European TSOs. You can find out more at FCR Cooperation.