Critical Grid Situation
Critical Grid Situation (CGS) is a coordination service performed by RCCs in order to facilitate a regional or cross-regional coordination in critical grid situations.
Critical Grid Situation (CGS) is defined as a critical situation which cannot be solved solely at national level. To solve the situation, coordination between one or more TSOs is needed.
ENTSO-E defines a critical situation in the following manner:
“A Critical Grid Situation is a potential emergency state, c.f. SOGL article 18(3), identified in the operational planning phase, when all the available regular countermeasures (Remedial Actions) are exhausted and therefore TSOs are required to take regionally coordinated extraordinary countermeasures.”
The CGS service is not mandated by European law, but requested by ENTSO-E. The CGS was defined as a service delivered by the RCCs at a SOC (System Operation Committee) meeting in September 2017.
The main purpose of this RCC service is to facilitate a regional or cross-regional coordination. The core of the CGS process is to facilitate and support exchange of information between relevant TSOs and relevant RCCs.
If a potential Critical Situation is realised, the necessary steps to facilitate the situation must be planned. The situation is a Critical Grid Situation when the normal, national relevant remedial actions are exhausted and extraordinary measures are needed.
Each Critical Grid Situation is unique, and a Critical Grid Situation can be triggered by a TSO or by a service. Typically, the CGS service is triggered by a TSO expecting a critical situation. In the Nordic Region, TSOs often act proactively, using the CGS service to avoid a potential critical situation.
The exchanged information can be a description of the expected operational situation, forecast for production, consumption and capacities for relevant corridors, weather forecast and its impact on the situation and the availability of the grid.
When the situation is solved, the Nordic RCC will document the process for the actual situation.