FFR, Fast Frequency Reserve

Fast Frequency Reserve (FFR) is procured to manage low-inertia situations in the power system. Inertia refers to the ability of the kinetic energy stored in the rotating masses in the electricity system to resist changes in frequency. There is an operational principle of the power system according to which the loss of a single power generation unit or HVDC transmission link should not cause the frequency to fall below 49.0 Hz. The magnitude of the instantaneous frequency change after a disturbance depends on the size of the power change caused by the disturbance, the power system's inertia, and the activation speed of the reserves. The needed volume of FFR depends on the prevailing inertia in the power system and the size of the reference incident.

FFR was introduced in the Nordic power system in May 2020. Fingrid procures FFR from a national market. In order to participate in the market, the Balancing Service Provider (BSP) must complete the prequalification process of the Reserve Unit and sign the FFR market contract.

The FFR market agreements are consistent in terms and content and are publicly available.

Data on the FFR reserve market can be found on the Reserve Market Information page and on the Fingrid Open Data service.