Main grid development plan 2015–2025 1 Summary ..................................................................................3 2 Introduction ................................................................................ 10 2.1 Document content and objectives ......................................................................................11 Contents 2.2 Legislative basis for the grid development plan ................................................................12 3 Background for Fingrid’s ten-year grid development plan ............ 15 3.1 Fingrid’s electricity grid and the Finnish electricity transmission system .......................16 3.1.1 History of the Finnish main grid ...............................................................................18 3.1.2 Fingrid’s history ........................................................................................................22 3.2 Grid development process ..................................................................................................23 3.2.1 Principles of grid development .................................................................................24 3.2.2 International main grid development cooperation ...................................................26 3.2.3 National grid development methods ........................................................................28 3.2.3.1 Planning of the main power transmission grid ..............................................29 3.2.3.2 Planning of the regional power transmission grid .........................................32 3.2.3.3 Formulating the Fingrid investment plan .......................................................38 3.3 Development of grid age ....................................................................................................39 3.4 Changes in the operating environment and future outlooks .............................................43 3.4.1 Electricity market ......................................................................................................43 3.4.2 Finland’s energy and climate policy .........................................................................45 3.4.3 Outlook for electricity production and consumption ................................................47 3.4.4 Technology ................................................................................................................49 3.4.4.1 Electricity transmission technologies .............................................................50 3.4.4.2 Other technology development .......................................................................52 3.4.5 Wind power ...............................................................................................................53 3.5 Scenarios . ..........................................................................................................................55 4 Fingrid’s ten-year grid development plan ...................................... 56 4.1 Development of the main electricity transmission grid.....................................................57 4.2 The development of cross-border capacity ........................................................................60 4.3 Development of the regional grid .......................................................................................63 4.3.1 The Lapland planning area .......................................................................................64 4.3.2 The Sea-Lapland planning area ...............................................................................67 4.3.3 The Oulu region planning area .................................................................................70 4.3.4 The Kainuu planning area .........................................................................................73 4.3.5 The Ostrobothnia planning area ...............................................................................76 4.3.6 The Central Finland planning area ...........................................................................80 4.3.7 The Savonia-Karelia planning area ..........................................................................83 4.3.8 The Pori and Rauma region planning area ...............................................................86 4.3.9 The Häme planning area ...........................................................................................89 4.3.10 The Southwest Finland planning area ....................................................................92 4.3.11 The Uusimaa planning area ....................................................................................95 4.3.12 The Southeast Finland planning area .....................................................................98 4.4 Connection of new production to the grid ........................................................................101 4.4.1 Nuclear power .........................................................................................................101 4.4.2 Wind power .............................................................................................................103 4.4.3 Small-scale production ...........................................................................................105 4.5 A summary of main grid investments ..............................................................................107 1 Summary Table of contents 3 1 Summary Development of the main grid is one of the core tasks of Fingrid Oyj, the company responsible for the electricity transmission system in Finland. Continuous develop- ment of the main grid ensures that the electricity transmission grid and the entire electricity system fulfil the quality requirements set for them as the needs for electricity transmission change. In the future, even greater reliability is expected from the power system in order to secure the essential functions of society. At the same time, changes in the operating environment create new challenges for the functioning of the power system. In the last few years, the construction of new production capacity has required the significant reinforcement of the main grid. The number of connections to the main grid has increased due to the improvement of the weather-related reliability of the distribution network and the construction of wind power. To promote the electricity market, cross-border transmission con- nections between Finland and neighbouring countries have been reinforced by constructing new connections and developing the existing ones. The aging grid is simultaneously being renewed, so that its technical capabilities will also remain on a high level and the system security of the entire electricity system can be ensured as reliably as possible. A major challenge for the development of the power system is presented by Eu- ropean society, which strives towards electricity production that generates lower emissions. The use of renewable energy sources is greatly increased through public subsidy, which increasingly disturbs the functioning of the electricity market. The increase in subsidised renewable energy lowers the market prices of electricity, which has had a detrimental effect on the profitability of conventional thermal power production, caused the closure of existing plants, and stopped new invest- ments. In Finland, this trend endangers the adequacy of electrical power for use by society. The problem cannot be solved by developing cross-border transmission connections alone, as this also lowers the market prices of electricity. In addition, the change in production structure from traditional synchronous machines to the use of power electronics has decreased the rotating mass of the power system. As a result, the inertia, or the natural ability to resist changes in frequency, of the Nordic power system has weakened. This is why, in the future, it may even be necessary to limit the power of large power plant units and HVDC connections in situations where inertia is low. Table of contents 4 1 Summary A main grid that has good transmission capabilities and operates reliably is a basis for the development of the electricity market. The developing electricity market together with the changing production structure require an increasing amount of cross-border transmission capacity. In the last few decades, Fingrid has purposefully developed electricity transmis- sion connections to neighbouring countries. The latest to be completed were an 800-megawatt HVDC connection between Finland and Sweden, and a 650- megawatt HVDC connection between Finland and Estonia. Fingrid’s view is that in the future, the cross-border transmission capacity between Finland and Sweden should be increased with a new 400 kV alternating current connection between northern Sweden and northern Finland. However, the completion date for this investment would only be in 2025. The needs of the electricity market are also supported by the development of Finland’s internal north-south and east-west connections. Plans include the reinforcement of north-south-oriented transmission by replacing aged 220 kV power lines with 400 kV lines from Oulujoki to Central Finland. Development of the main grid is an essential part of power system development The main grid development plan presents the development needs of Fingrid’s main grid and planned investments for the next ten-year period. The development plan is based on regional grid plans compiled by Fingrid in cooperation with its cus- tomers, and it is coordinated with the development plan for the Baltic