Main grid contract

Part of the main grid contract are the supply of reactive and real-time information exchange application instructions. The supply of reactive application instruction is applied for the supply and monitoring, and for calculating the supply limits, of reactive power transmitted via the Customer’s connection points in the main grid. The application instruction additionally specifies the guidelines how to maintain reactive power reserves in generators. The real-time information exchange shall be applied to the real-time information exchange related to the maintenance of system security and to the technical implementation and definition of real-time information exchange.

Main grid connections must fulfil the technical requirements set out in Fingrid’s General Connection Terms (YLE). In addition to the General Connection Terms, power plants must fulfil Fingrid's Specifications for the Operational Performance of Power Generating Facilities (VJV).  Fingrid also has published Grid Code Specifications for Demand Connections (KJV)

In accordance with the Electricity Market Act (386/1995), the Energy Authority has verified the General Connection Terms and the Specifications for the Operational Performance of Power Generating Facilities.

Electricity transmission in the main grid

The main grid contract is used to agree on the customer’s rights to transfer electricity from and to the main grid via its connection points, service terms and prices, supply of reactive power, maintenance of reactive power reserves, and real-time information exchange related to maintaining system security. The main grid contract can be signed after the terms of main grid connection have been agreed with the customer in a connection agreement.

Together with customers, we ensure that the electricity system is maintained and used in a technically appropriate manner. Our aim in power system operation is continuous information exchange with our customers. We strive to plan electricity grid transmission interruptions together and to notify our customers about disturbances as early as possible.

Reactive power

Reactive power is delivered and received in the customer’s connection point or connection points. The aim of the reactive power tariff is to guide the use of reactive power optimally, considering technical aspects such as transmission capacity. Power exceeding the reactive power limits is invoiced. 


Figure. The reactive power window determines the amount of reactive power delivered to and received from the main grid without separate compensation for each connection point.

The operation and maintenance of the reactive power is agreed in the Main Grid Contract Appendix 1 Main Grid Service Terms and Conditions (KVPE2016) and in the Supply of Reactive Power and Maintenance of Reactive Power Reserves application instructions. 

Reactive power reserves

The reactive power reserves have been based on obligation since the beginning of 2016. The operational and structural requirements for reactive power reserves are defined in detail in the  Specifications for the Operational Performance of Power Generating Facilities (VJV).

Real-time information exchange

The scope of real-time information related to maintenance of main grid system reliability is agreed separately with each customer by taking system security of the electricity system into consideration. The real-time measurement and state information must be available in Fingrid’s operation control system when a new power plant or substation is connected to the electricity network.

Real-time information exchange is agreed upon in the main grid contract and the information exchange application instructions.