Procurement of automatic frequency restoration reserve from Estonia has begun
Fingrid and Elering have prepared a pilot project to enable Estonian electricity market participants to offer capacity on Fingrid’s automatic Frequency Restoration Reserve (aFRR) hourly market.
Preparations for the pilot project are now complete and operation has begun. The first offers were received from Elering at the start of August 2021.
The automatic frequency restoration reserve is a centralised, automatically activated reserve. The reserve is activated in the event of a frequency deviation in the Nordic synchronous area when the transmission system operator sends a power change signal. In practice, the activation of the reserve from Estonia is implemented in such a way that Elering forwards Fingrid’s power change signal to the Estonian reserve provider, which regulates its reserve resource (such as a power plant) according to the signal. At the same time, the Estlink submarine cable between Estonia and Finland is regulated by the same amount, so that the impact of the adjustment takes place in Finland.
For example, if Finland is in a state of over-frequency, the Estlink connection increases exports to Estonia or reduces imports to Finland. Conversely, in the event of under-frequency, the Estlink reduces exports to Estonia or increases imports to Finland.
The Estonian offers delivered by Elering are included in the hourly market for automatic frequency restoration reserves, which is maintained by Fingrid, on the same terms as for Finnish offers. Estonian offers can only be used if there is spare transmission capacity in the Estlink connection after the day-ahead market for electricity. The procurement volume from Estonia is limited to 35 MW, while Fingrid’s total procurement volume varies between 60 MW and 80 MW.
The automatic frequency restoration reserve will become increasingly important as renewable and variable forms of electricity generation account for a greater share of the total energy in the power system. Procuring reserves from Estonia will increase the offering on the reserve market and help Fingrid to boost its cost-efficiency.
Antti Hyttinen, Specialist, Fingrid, tel. +358 30 395 5353
Jyrki Uusitalo, Unit Manager, Fingrid, tel. +358 30 395 5181