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Usage of interconnectors

Coupling of national electricity markets in Europe creates the prerequisites for the constantly growing cross-border electricity trade. Following transparent procedures, electricity traders can procure transmission capacities on the lines operated by 50Hertz. Transmission capacities between the countries lead to an active energy exchange and the electricity supply within the EU becomes more efficient and climate-neutral in general. Moreover, the cross-border lines offer additional opportunities to balance fluctuation in generation. This means an increased security of supply for all.

The technically available transmission capacities on the international lines cannot be provided for trade to the full extent. As transmission system operator (TSO), 50Hertz is particularly responsible for grid security and therefore maintains reserves that enable us to compensate for fluctuations and guarantee failsafe performance.

For the purpose of non-discriminating and transparent international electricity trading, the transmission capacity and safety margin of the relevant connections (interconnectors) are first calculated on the basis of defined models. 50Hertz constantly publishes the resulting currently available grid capacity. Transmission capacities are allocated on the platforms provided to that end or via power exchanges, both in the long term (for yearly and monthly periods) and in the short term (day-ahead and intraday). As a result, the physical electricity flow shown here is not always identical to the commercial, i.e. traded electricity flow.

Capacity calculation

Calculation of the total available transmission capacity between the relevant bidding zones as well as the safety margins to guarantee grid security is legally stipulated. In accordance with article 50(2) of  Regulation (EU) 2019/943, there is a general model that has been approved by the regulatory authorities. In detail, the calculation models vary depending on the technical conditions of the interconnectors and are, for instance, much simpler for a directly controllable high-voltage direct current transmission line (HVDC) than for alternating current (AC) lines. All calculation models described below have been approved by the German national regulatory authority (Bundesnetzagentur).

Additionally you can find information on outage planning and outages on this website.

Interconnections between Germany (50Hertz) and Denmark (Energinet)

The bidding zone border DE/LU-DK2 is comprised of the two interconnectors "KONTEK" and "Kriegers Flak Combined Grid Solution (KF CGS)" and is assigned to the capacity calculation region (CCR) Hansa. Calculation of the transmission capacity available for electricity trading between the bidding zones DE/LU and DK2 is regulated by the corresponding capacity calculation methods of the CCR Hansa. The special features of the two interconnectors KONTEK and KF CGS described below are taken into account therein.

KONTEK

To calculate the available transport capacity for the KONTEK link, an HVDC transmission line with controllable active power transfer, we only take into account the provision of grid losses. Grid losses occur each time electricity is transmitted as a result of the energy needed for the transport itself. The energy required to cover the grid losses on the KONTEK link is provided in eastern Denmark, regardless of the direction of the load flow. Specifically, 2.5 % (15 MW) of the capacity is required for the transmission of the grid losses and therefore cannot be made available to the market. Under normal operating conditions, the transmission capacity made available for electricity trading is therefore 600 MW in south-north direction and 585 MW in north-south direction. 

The model approved by the German regulatory authority to calculate the total transmission capacity on the KONTEK link can be found under the following link:

Model to calculate the transmission capacity on KONTEK (in German) (Download PDF, 76,1 KB)

KF CGS

The interconnector KF CGS started its commercial operation on 15.12.2020. The connection represents a technical novelty, as an interconnector and national connections of offshore wind farms have been combined here for the first time (details can be found on the KF CGS project website). Therefore, when calculating the transmission capacity available on KF CGS for electricity trading between the bidding zones DE/LU and DK2, the electricity feed-in to be expected from the integrated offshore wind farms must be considered. These technical specificities are also taken into account by the decision of the EU Commission of 11 November 2020 to grant a derogation to KF CGS pursuant to Article 64 of Regulation (EU) 2019/943. This derogation stipulates that only that part of the interconnector capacity of the KF CGS can be used for electricity trading which is not required to transport the electricity generated by the integrated German and Danish offshore wind farms to the respective national transmission grids. Accordingly, the basis for the calculation of the minimum capacity pursuant to Article 16 (8) of Regulation (EU) 2019/943 is the remaining capacity of KF CGS after deduction of the capacity required to transport the electricity feed-in from the connected wind farms to the respective national transmission systems as forecasted day-ahead. 

During operation the physical power flow on KONTEK and KF CGS is optimized aiming among other things at a minimisation of the incurring grid losses. 50Hertz and Energinet are currently researching whether changes in the provision of the grid losses are economically reasonable. Should this be the case, 50Hertz and Energinet will make appropriate adjustments after consultation with the German and Danish regulatory authorities and after timely prior notice.

Furthermore, due to scheduled works or disturbances in the transmission grids of 50Hertz and/or Energinet, the available transport capacity in the relevant transmission grid may be restricted. As a result, limitations of the transmission capacity available for the market between the bidding zones DE/LU and DK2 can occur.

Interconnections between Germany (50Hertz) and Poland (PSE) and the Czech Republic (ČEPS) respectively

Since the go-live of the Flow-Based Market Coupling in the CCR Core on 09.06.2022, the transmission capacities available for international electricity trading between Germany and Poland and between Germany and the Czech Republic respectively are determined for the day-ahead market according to the capacity calculation methodology for the day-ahead timeframe linked on the following page.

The intraday capacities are derived from the leftover Day-Ahead capacities according to the capacity calculation methodology of the CCR Core for the Intraday timeframe, which is also published under the following link. After validation by 50Hertz, the intraday capacities are given into a bilateral coordination process with PSE for the DE-PL border, and to a trilateral coordination process with TenneT and ČEPS for the DE-CZ border.

Link to the capacity calculation methodologies of the CCR Core

The transmission capacities available for international power trading in the mid- and long-term timeframes are calculated according to the methodology described under the link below:  

 General model for calculating the total transmission capacity and the security margin on the DE-CZ and DE-PL borders in the mid- and long-term timeframes (in German) (Download PDF, 813 KB)

The mid- and long-term capacities for transmission of electric energy, which are made available to the market in this way, are determined on the basis of theNet Transfer Capacities (NTC) method (Download PDF, 227 KB).

Up-to-date grid capacities

The requirements for cross-border electricity transport keep increasing due to the growing European electricity trade. The available transmission capacities of the cross-border interconnectors, however, are often not enough. The available line capacities therefore need to be managed without discrimination according to a market-oriented and transparent procedure.

Below you can find current data on grid capacity at the hubs of the 50Hertz grid area with transmission system operators in Poland (PSE), the Czech Republic (ČEPS) and Denmark (Energinet.dk).

Disclaimer

All figures published on the following page have been determined and are made available to the best of our ability. We accept no responsibility for accuracy and completeness, or for the occurrence of the described scenario. The capacity offered and awarded in the auctions may differ from the indicated figures; any legal claims shall be excluded.

No liability is accepted for any damage resulting from temporary non-availability or inaccuracy of data.

Should the data be temporarily unavailable for technical or other reasons, 50Hertz will make every effort to immediately restore access to the data.

50Hertz reserves the right to subsequently change data should this be required for correction purposes.

Grid capacity at the border between 50Hertz and Energinet

The indicated figures represent the total of capacities of the interconnection capacity for both directions of the load flow.

Date From To 50Hertz ⇝ Energinet.dk [MW] Energinet.dk ⇝ 50Hertz [MW]
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Download CSV files for each month

Below you can download the presented grid data in CSV format for each month.

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Annual forecast of the grid capacity at the border between 50Hertz and Energinet.dk

Here you can find the lowest NTC figures (Net Transfer Capacities method) per month for the current year.

Year Month 50Hertz ⇝ Energinet.dk [MW] Energinet.dk ⇝ 50Hertz [MW]
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Below you can download the presented grid data in CSV format for each year.

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Monthly forecast of the grid capacity at the border between 50Hertz and Energinet.dk

The lowest NTC figures (Net Transfer Capacities method) per calendar week are shown here for the respective eight following calendar weeks.

Year Week 50Hertz ⇝ Energinet.dk [MW] Energinet.dk ⇝ 50Hertz [MW]
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Below you can download the presented grid data in CSV format for each month.

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Weekly forecast of the grid capacity at the border between 50Hertz and Energinet.dk

The lowest NTC figures (Net Transfer Capacities method) per day are shown here for the respective following fourteen days.

Date 50Hertz ⇝ Energinet.dk [MW] Energinet.dk ⇝ 50Hertz [MW]
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Below you can download the presented grid data in CSV format for each month.

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Daily forecast of the grid capacity at the border between 50Hertz and Energinet.dk

The lowest NTC figures (Net Transfer Capacities method) per hour are shown here for the respective following 48 hours.

Date Time 50Hertz ⇝ Energinet.dk [MW] Energinet.dk ⇝ 50Hertz [MW]
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Below you can download the presented grid data in CSV format for each month.

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Grid capacity at the border between 50Hertz and ČEPS/PSE

The indicated figures represent the total of capacities at all hubs for both directions of the load flow.

Date From To 50Hertz ⇝ ČEPS/PSE [MW] ČEPS/PSE ⇝ 50Hertz [MW]
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Download CSV files for each month

Below you can download the presented grid data in CSV format for each month.

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Annual forecast of the grid capacity at the border between 50Hertz and ČEPS/PSE

Here you can find the lowest NTC figures (Net Transfer Capacities method) per month for the current year.

Year Month 50Hertz ⇝ ČEPS/PSE [MW] ČEPS/PSE ⇝ 50Hertz [MW]
Show more Show less

Below you can download the presented grid data in CSV format for each month.

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Monthly forecast of the grid capacity at the border between 50Hertz and ČEPS/PSE

The lowest NTC figures (Net Transfer Capacities method) per calendar week are shown here for the respective eight following calendar weeks.

Year Week 50Hertz ⇝ ČEPS/PSE[MW] ČEPS/PSE ⇝ 50Hertz [MW]
Show more Show less

Below you can download the presented grid data in CSV format for each month.

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Weekly forecast of the grid capacity at the border between 50Hertz and ČEPS/PSE

The lowest NTC figures (Net Transfer Capacities method) per day are shown here for the respective following fourteen days.

Date 50Hertz ⇝ ČEPS/PSE [MW] ČEPS/PSE ⇝ 50Hertz [MW]
Show more Show less

Below you can download the presented grid data in CSV format for each month.

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Daily forecast of the grid capacity at the border between 50Hertz and ČEPS/PSE

The lowest NTC figures (Net Transfer Capacities method) per hour are shown here for the respective following 48 hours.
With the start of the CORE flow-based process on 09.06.2022, no more Day-ahead NTC values will be determined for the borders CTA|DE(50Hertz) <> CTA|PL-CZ anymore. 50Hertz will therefore stop publishing Day-ahead NTC values for these borders starting from 09.06.2022 00:00.

Date Time 50Hertz ⇝ ČEPS/PSE [MW] ČEPS/PSE ⇝ 50Hertz [MW]
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Below you can download the presented grid data in CSV format for each month.

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Capacity allocation

The limited available transmission capacities between the grid area of 50Hertz and the grid areas of the neighbouring transmission system operators are currently allocated in the long term for yearly and monthly periods. Additionally, in the short term, transmission capacities are allocated in the day-ahead as well as in the intraday timeframe. Allocation of the capacities at the various borders in the individual timeframes is carried out via the platforms of the companies listed below which are in charge of carrying out the respective capacity allocations. You will find detailed information on the allocation of capacities listed under the links to the respective platforms.

Explicit and implicit auctions

In case of an explicit allocation, the transmission capacity is allocated independently of a commercial electricity transaction. In addition to the market for commercial electricity transactions, there is another separate market on which the rights for the use of capacity can be acquired. These two markets do not only exist separately from each other but also differ in terms of timing.

In case of implicit allocations, the transmission capacity is allocated together with the commercial electricity transaction. This allocation process requires close coordination between transmission system operators and power exchanges.

Interconnection between Germany (50Hertz) and Denmark (Energinet.dk)

Yearly and monthly capacity

Yearly and monthly auctions on the border between Germany and Denmark are carried out in the form of explicit auctions by the Joint Allocation Office (JAO). The up-to-date information on these auctions can be found on the homepage of JAO: www.jao.eu

Day-ahead capacity

On the border between Germany and eastern Denmark, the daily capacity is allocated within the framework of the Multi-Regional Coupling (MRC). The up-to-date information on these implicit auctions on the border between Germany and eastern Denmark (within the framework of the MRC) can be found on the homepage of Nord Pool AS:
www.nordpoolgroup.com

The fall-back solution for MRC is the application of explicit daily shadow auctions on the borders between Germany and Denmark. The up-to-date information on these auctions can be found on the homepage of the Joint Allocation Office (JAO): www.jao.eu

Intraday capacity

The capacity allocation in the intraday timeframe on the bidding zone border between Germany and eastern Denmark is integrated into the European single intraday coupling (SIDC). Available capacity is made available to the market participants via an implicit continuous allocation process, i.e. market participants only need to make their trading deals at a local power exchange (Nominated Electricty Market Operator – NEMO), whereas they do not need to procure the required commercial cross border capacities separately. More Information on the SIDC can be found on the projects’ website.

Interconnections between Germany (50Hertz) and Poland (PSE) and the Czech Republic (ČEPS) respectively

Yearly and monthly capacity

Yearly and monthly auctions on the borders between Germany and Poland and between Germany and the Czech Republic respectively are carried out in the form of explicit auctions by the Joint Allocation Office (JAO). The up-to-date information on these auctions can be found on the homepage of JAO: www.jao.eu

Day-ahead capacity

The capacity allocation in the day-ahead timeframe on the bidding zone borders between Germany and Poland and Germany and Czech Republic respectively is integrated into the European single day-ahead coupling ("Single Day-Ahead Coupling" - SDAC). The capacities available for cross-border trading are allocated to the market participants in an implicit allocation process, i.e. the market participants only need to conclude local trading transactions at a power exchange (Nominated Electricity Market Operator - NEMO) and do not need to procure the cross-border trading capacity separately. More information on the SDAC can be viewed on the project's central website.

Intraday capacity

The capacity allocation in the intraday timeframe on Germany’s bidding zone borders towards Poland and the Czech Republic has been integrated into the European single intraday coupling (SIDC) since November 2019. Available capacity is made available to the market participants via an implicit continuous allocation process, i.e. market participants only need to make their trading deals at a local power exchange (Nominated Electricty Market Operator – NEMO), whereas they do no longer need to procure the required commercial cross border capacities separately, as done before the SIDC integration. More Information on the SIDC can be found on the projects’ website. 

Load flows

A load flow is the physical electricity flow, i.e. the effectively measured energy volume per time unit on the lines. Under normal operating conditions, it is always available and differs from the commercial electricity flow that is traded across the borders via the interconnectors.In accordance with § 17 (1) of the German Ordinance on Power System Access (StromNZV), the overview shows the cross-border load flows at the hubs of the transmission grid of 50Hertz to the neighbouring grid areas of the countries of Denmark, Poland and the Czech Republic.

CONTACT

Gert Schwarzbach

Head of Interconnectors