What: A market where balancing service providers (BSPs) can offer bids for automatic frequency restoration reserves (aFRR) capacity to the transmission system owners (TSOs - i.e. Svenska kraftnät, Energinet, Fingrid and Statnett). aFRR can be activated by an automatic control device designed to get the frequency back to the normal frequency band (49,9 – 50,1 Hz) or get the area control error (ACE) to zero. aFRR replace the fast-responding frequency containment reserves (FCR).  

How: aFRR balancing capacity is procured by the TSOs before the day-ahead market, taking into account geographical distribution and network constraints. As available aFRR resources are unevenly distributed across the market, the TSOs will reserve some cross-zonal capacity for the aFRR capacity market if this is found to be the socio-economically optimal solution. 

Why: TSOs must ensure that they have sufficient aFRR resources to handle possible incidents during operations. As aFRR resources are unevenly distributed across the Nordics, reserving cross-zonal capacity for aFRR makes it possible to procure aFRR capacity across bidding zones

Market handbook FRR CM