The Nordic countries are pursuing an aggressive decarbonisation effort, which is changing the electricity landscape in the region. Finland aims to become carbon neutral by 2035; Sweden by 2045 [with interim milestones for 2030 (63 per cent) and 2040 (75 per cent)]; Denmark by 2050 (with a 70 per cent milestone for 2030); and Norway aims to become a low-emission society (with 90-95 per cent reduction) by 2050. To achieve these targets, countries are ramping up their renewable capacities rapidly.

To ensure a smooth transition, the four Nordic transmission system operators (TSOs) – (Denmark), Fingrid Oyj (Finland), Statnett SF (Norway) and Svenska kraftnät AB (Sweden) – have been closely coordinating and cooperating to establish a common perspective on the overall development of the Nordic power system. This was presented by the four TSOs in a recently released (November 2021) report on the Nordic Grid Development Perspective (NGDP) 2021 as well as a webinar organised by them on the subject. The analyses are based on a common Nordic scenario – Climate Neutral Nordics – for years 2030 and 2040, created by the Nordic TSOs. The scenario is based on European Network of Transmission System Operators for Electricity (ENTSO-E) Ten-Year Network Development Plan 2020 (TYNDP) Distributed Energy scenario as well as the latest national scenarios. The TSOs performed the identification of system needs (IoSN) analysis for the Nordic grid in the created scenario. The report also presents a more detailed outlook on certain selected focus areas such as north-south transmission needs, resource adequacy and offshore wind (OSW).

The NGDP is requested by the Nordic Council of Ministers, an intergovernmental forum to promote regional cooperation, and is published every second year. Nordic Grid Development Plan 2019 (NGDP2019) described the status of the ongoing and planned investments in the region and investigated the need for increased transmission capacities between Nordic countries over five ‘corridors of interest’. However, the latest report presents a common Nordic view on selected key topics rather than presenting a traditional technical grid development plan. Therefore, the name of the 2021 report has been changed to ‘perspective’ instead of ‘plan’, as used previously. Nevertheless, the report provides an update on the Nordic corridors of interest to NGDP2019.

Climate Neutral Nordics scenario 

The report points out that a lot has changed since NGDP2019 in terms of forecast for electricity consumption and renewable capacity addition (refer to Figure 1). Nordic annual electricity consumption is expected to grow from 400 TWh in 2020 to 530 TWh (33 per cent growth) by 2030 and 655 TWh (65 per cent) by 2040. Hydrogen production/power-to-X (P2X) accounts for the highest demand growth. Further, electrification of existing and new industry as well as transport along with data centres’ consumption are the key drivers for demand growth in the Nordics. The scenario also predicts an exponential growth in renewable energy sources (RES) from 85 GW in 2020 to 145 GW (70 per cent) in 2030 and further to 185 GW (122 per cent) by 2040. The levelised cost of electricity (LCOE) of RES continues to fall, thus enabling a huge amount of installed capacity to meet the increasing demand.

The scenario shows that the electricity transfer needs in the Nordic system are increasing and the existing patterns of energy flow can change significantly. There is a need to reinforce the networks in the Nordic countries and major investments are needed to increase network capacity in several Nordic corridors. This will require both construction of new network as well as solutions to increase capacities without traditional grid investments. The needs identified based on the Climate Neutral Nordics scenario will serve as a vital input to a more detailed planning processes.

Identification of System Needs

Transmission needs are expected to increase in the future when consumption increases and huge amounts of RES generation is integrated into the Nordic power system. While the analysis shows large price differences in many corridors, it may not necessarily be addressed through investments in new grid. Over time, market dynamics are likely to lead to more equal prices, which will reduce the need for such investments. Alternative options for increasing grid capacity will have to be explored through measures such as dynamic line rating (DLR), series compensation, static var compensator/static synchronous compensator devices (SVC/STATCOM), voltage control solutions, and system protection schemes. The Nordic TSOs are investing in the most cost-efficient options for increasing grid capacity.

The NGDP2019 studied five bilateral corridors: Norway-Sweden, Finland-Sweden, Finland-Norway, Norway-Denmark and Denmark-Sweden. The report gives an update of the work done since the analyses and further development of the corridors.

TSOs plan huge investments in future grids

The Nordic TSOs are making substantial investments to increase the capacity of the grid over the next 10 years. Energinet is building about 3,000 km of cables and lines, 8 new substations and has planned investments of about EUR7.8 billion. This value excludes the investments in the proposed energy islands. Fingrid plans to build 3,700 km of lines, 41 new substations and invest about EUR2.1 billion. Statnett is building 2,500 to 4,000 km of lines, 30 to 35 new substations and making investments worth EUR6 billion to EUR10 billion. Svenska kraftnät is building 800 km of lines, 20 to 30 new substations and making investments totalling about EUR8.1 billion. Investments include TSOs’ plans to reinvest in several substations and lines as well as make equipment upgrades.

Jointly, the Nordic TSOs will build over 10,000 km of lines, more than 100 new substations, and invest around EUR25 billion over the next decade (refer to Table 1 for summary; refer to Figure 2 for status of grid development projects in the Nordics).

Focus area studies

North-south transmission needs: Due to changes in both electricity production and consumption, there will be modifications to the overall north-south flow patterns in the Nordic grid. The grid is likely to experience power flows in the opposite direction to what is predominant today. That said, in the majority of corridors, the north-south flow will not decrease and will be significant in many instances. The Nordic grid must therefore continue to have strong north-south connections. To avoid over-investments in grid capacity due to volatile wind power, P2X and other flexibility providers [such as demand-side response (DSR), storage and electric vehicles] can have a role to play as a complement to grid reinforcements.

There will be significant changes in the Nordic demand-supply balance. Country-wise, Denmark is in a key position when developing connections between the Nordic countries and continental Europe. It is in the process of expanding both onshore and offshore renewables connected in the southern and western parts. New high voltage direct current (HVDC) projects are being planned, both internally and in the North and Baltic seas, to expand capacity to the neighbouring countries to handle these new flows. In Finland, most of the new onshore wind power will come up in the north, while majority of demand is expected to stay in the southern part. This will require large investments in north-south transmission lines. Potential HVDC connections from southern Finland to Estonia and Sweden will further increase the need for internal grid investments.

Sweden faces the challenge of using mainly wind power to balance both consumption growth and replace power production from decommissioned nuclear units. These developments could increase significantly the north-south transmission needs. Compared to Sweden and Finland, Norway has a more decentralised power system where consumption and production is spread across the whole country. Statnett has plans to upgrade all 300 kV lines to 420 kV lines by 2040.

Resource adequacy: In the Climate Neutral Nordics scenario, the Nordics is a surplus area with respect to energy production in 2030 and 2040. But the power margin (which is equal to the difference between the available production and current consumption) at the Nordic level will become negative in an increasing number of hours towards 2040 as intermittent production plays a large role. The amount of time with negative power margin in the Nordics increases from 3 per cent to 28 per cent from 2030 to 2040. At the same time, the power margin at the most negative falls from -16 GW to -38 GW. In this context, the transmission grid serves as a valuable enabler for exchange of resources between regions to help resolve some adequacy issues.

In cases of similar weather conditions in the entire region, to ensure the security of supply, the Nordic countries may import from surrounding countries on the continent or the UK. Import capacity in 2030 in the Nordics is expected to be around 12 GW – though significant, it is lower than the power margin at the most negative, warranting the need for additional measures. Greater flexibility in consumption and peak plants based on biofuels/hydrogen, fuel cells or increased capacity in reservoir hydropower, will become increasingly important in this context.

Country-wise, in 2040, the estimated maximum negative power margin in Denmark and Sweden is more than -10 GW each. Finland, which currently has approximately 5 to 7 GW of the power margin deficit, is expected to cover its deficits by imports requiring strong interconnections. Norway, which has a positive margin today, is expected to have a negative power margin of -1.7 GW in 2030 and -2.5 GW in 2040, and thus will be in the tightest situation.

Offshore wind: As the EU aims to become climate neutral by 2050, OSW is expected to play a greater role. The EU aims to achieve 60 GW of OSW capacity by 2030 and 300 GW by 2050. A large part of the new capacity in the Baltic Sea and the North Sea is expected to be connected to the Nordics. The number and size of planned OSW farms are rapidly growing in this region. Besides constructing radial lines, the massive offshore deployment may require new offshore grids that connect OSW capacity located far from shore to hubs that can be connected to multiple countries (such as energy islands). Though such offshore grids are not technically mature enough, they are needed to integrate offshore wind to multiple markets, meet the expected increase in electrification consumption and support the development of green fuel (P2X).

The Nordic TSOs expect a substantial growth in connected OSW power over the next 2 decades. The total connected OSW capacity will increase from 2.5 GW currently to 17 GW by 2030 and 35 GW by 2040. The Nordic countries are following different approaches to OSW development. In Denmark and Norway, areas for potential new OSW parks are identified by the respective governments and are awarded through tender. In 2020, the Norwegian government opened two areas for application – Sørlige Nordsjø II and Utsira Nord, which together have a potential for 4.5 GW of OSW. The Danish government is planning for a 3.5 GW radial connected wind capacity, including HesselØ, Thor and Kriegers Flak, and has decided to construct two energy islands, one in the North Sea with an initial capacity of 3 GW expandable up to 10 GW, and one in the Baltic Sea near Bornholm with 2 GW capacity. In Sweden and Finland, developers submit applications for potential wind farms. For example, Fingrid and Svenska kraftnät have received approximately 20 GW and 120 GW of OSW connection inquiries respectively.

Similarly, the TSOs have differing roles with respect to OSW connections. In Finland and Denmark, the project developer pays for the connection to the grid for traditional radial connections. In Sweden, a new policy has been proposed, which will come into force from January 2022 and where Svenska kraftnät will be responsible for connections within territorial waters for those offshore connections that will be built to promote the fulfilment of the target of 100 per cent renewable electricity production by 2040. Norway is still in the process of finalising a policy, but a Parliamentary whitepaper indicates that developers will be responsible for the cost for connection to the shore as well as the necessary grid reinforcement onshore.

While the planning of radial grid connections for OSW is relatively straightforward and national in nature, hybrid offshore solutions, with connections to several countries, may require the development of completely new grid planning principles, such as dimensioning of the offshore grid, fault withstand, interoperability as well as system operation principles.  

The way forward

NGDP2021 highlights that the Nordic region is attractive for future energy intensive investments and that the future power system will be more volatile and complex, increasing the demand for flexibility and new technologies.

The Nordic TSOs are working closely to ensure that transmission becomes an enabler for achieving regional climate and energy targets. Besides their collaboration for NGDP, the TSOs are in the process of formulating a common Nordic strategy for the next 10 years (up to 2030) to meet the developments in wind power and sector integration. The TSOs released the Nordic TSO draft strategy in early 2021. The strategy, which will provide a broad view on transmission planning, system operation and markets, will be published in the next Nordic TSOs’ joint solutions report, which is released once every two years and is due in 2022. Further, the Nordic TSOs have identified the need for developing mid-term collaboration both in operational and planning aspects to complement the long-term collaboration. Net net, the transmission sector in the Nordic region is set for exciting times ahead.

This article has been sourced from Global Transmission Research