Grid code specifications

By virtue of the system responsibility on Finland, Fingrid has set the requirements for electrical systems and power plants connected to the Finnish power system. Whereas general principles and terms for connections are defined in Fingrid's General Connection Terms (YLE) and the of the Main Grid Contract (KVS), more detailed requirements are given in Grid Code Specifications which are presented separately for power plants, demand connections (consumption), grid energy storage systems and HVDC connections. The Terms and Specifications also apply to electrical systems and power plants connected to the customer's electricity network.

The Grid Code Specifications describe the technical and operational requirements of the equipment to be connected and the process by which the exchange of information in projects must be carried out. By complying with the requirements, we ensure that the connected equipment can withstand the voltage and frequency fluctuations caused by the power system, they do not cause interference in the power system and that they operate reliably in different operating situations and also during disturbances. The requirements also help network operators to gain access to the necessary information about the equipment.

Compliance with and verification of Grid Code Specifications is the responsibility of the Connecting Party connecting to the grid. It is important to take this into account in the agreements with suppliers. Similarly, it is advisable to start planning and exchange of information well in advance between the supplier, the related customer and the grid company, and possibly also with the distribution network company.

The current Grid Code Specifications are presented on their own pages, which also contain instructions and other background documents that complement the actual Grid Code Specification documents. The requirements are divided as follows:

- Grid Code Specifications for Power Generating Facilities, VJV
- Grid Code Specifications for Demand Connections, KJV
- Grid Code Specifications for High Voltage Direct Current Systems, HVDC
   (only Finnish version available)
- Grid Code Specifications for Grid Energy Storage Systems, SJV

Previous (obsolete) Grid Code Specifications and related material can be found on the "Archive" page.

Following instructions closely related to Grid Code Specifications can be found on the Main grid contract page:

Supply of reactive power and maintenance of reactive power reserves

The document describes the requirements for reactive power reserves for power plants connected to 110 kV and 400 kV and calculation of reactive power limits applicable at the point of connection.

Real-time information exchange

The document describes the real-time measurements required to be sent to Fingrid. The measurements must be implemented before the power supply through the connection point can begin.


Lasse Linnamaa
Expert, Power Plants
tel. +358 30 395 5362