Foundation laid for DolWin6 converter


With a dozen operating offshore connection systems for wind farms in the German North Sea totalling a transmission capacity of 7.132GW, the Dutch-German transmission system operator (TSO) TenneT has already in 2019 exceeded the German government’s expansion target for offshore wind energy capacity for 2020 by more than half a million GW. A further 900MW will be provided by DolWin6, like the predecessor projects DolWin3 and BorWin3 a high-voltage direct current (HVDC) connection. The DolWin kappa offshore platform in the Wadden Sea near the island of Norderney will convert the three-phase wind current into DC for transmission via a 45 kilometre submarine cable to the East Frisian mainland and from the landing point via an underground cable, also around 45 kilometres long, to the TenneT site in Emden/East.

Here, the TSCNET shareholder is constructing the DolWin6 onshore converter station and a substation on 23,500m² to reconvert the DC into three-phase current for feeding into the onshore extra-high voltage grid. A significant milestone for DolWin6 was reached on 27 May: The laying of the foundation at the converter construction site was celebrated in Emden/East by embedding a time capsule with coins, a regional daily newspaper, and construction plans into the foundation stone. Due to the Covid-19 pandemic, the event was only celebrated with the most important project managers from TenneT and the plant constructor Siemens.

Concrete preparations for DolWin6 began in the summer of 2017 and 2018 with horizontal drilling on Norderney. In September 2019, the foundation work commenced in Emden/East. Work on the DolWin kappa offshore platform at a dockyard in Cádiz/Andalusia also started in mid-2019 and the DolWin6 cable laying will follow from summer this year. The completion of the HVDC offshore connection is scheduled for 2023.

TenneT celebrated the laying of the foundation stone for the DolWin6 converter in Emden/East (picture: TenneT)

> See TenneT press release, in German (html)

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New 380kV line Airolo-Lavorgo in approval phase


The first plans to increase the transmission capacity of the overhead lines in the Leventina Valley in the Swiss canton of Ticino date back to 1997. Today, the upgrade of the 23-kilometre-long line between the Airolo and Lavorgo substations from 220kV to 380kV is part of the “Strategic Grid 2025”, the infrastructure expansion plan of the Swiss transmission system operator (TSO) Swissgrid. This is a future-oriented measure of ecological value, because the TSCNET shareholder is not only enhancing capacity and security of supply for Ticino and the whole of Switzerland, but thanks to the new overhead line and the subsequent upgrade of the lines in the Maggia Valley, the hydroelectric power plants in Ticino will no longer be subject to output restrictions.

The planning corridor was approved by the Swiss Federal Council in March 2016, which provides for the line to run along the western bank of the Ticino River, which flows through the Leventina Valley. Based on this decision, Swissgrid – in close cooperation with the Canton of Ticino, municipalities and citizens’ communities – has designed the final routing, which has now been submitted for approval to the Swiss Federal Inspectorate for Heavy Current Installations (“Eidgenössisches Starkstrominspektorat”, ESTI).

The Airolo-Lavorgo line complements the connection under construction between Chippis in Valais and Lavorgo and secures the electricity supply of Ticino with an additional 380kV system. According to the plans now submitted to ESTI, the new route of the line in the Leventina Valley is to run far from any residential areas. Once the new line is operational, the current 220kV line, which in comparison is much closer to settlements, can be dismantled. The completion of the new lines in both the Leventina and the Maggia Valley, scheduled for 2035, will, under current planning, ultimately enable the disassembly of more than 60 kilometres of overhead lines.

Swissgrid has submitted the application for building the 380kV line Airolo-Lavorgo (picture: Swissgrid) 

> See Swissgrid media release (html)

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Amprion Market Report shows encouraging trends


The intermeshed European electricity market today requires constructive cooperation between all actors and organisations. Amprion, one of the four German transmission system operators (TSOs), considers the efficiency of cooperation at European level a key prerequisite for continental security of supply and the success of the energy transition. For this reason, the TSCNET shareholder was and is involved in numerous regional and European initiatives on system operation, network planning, and market integration. Also, Amprion is an observant analyser of the European market development, especially in the Central Western Europe (CWE) region and annually provides the Market Report for the CWE countries. The 2020 edition for the period 2015 to 2019 has just been released.

The Market Report is based on data from Flow-Based Market Coupling (FBMC) introduced by the six CWE countries (Austria, Belgium, France, Germany, Luxembourg, the Netherlands, and Belgium) in May 2015. By involving the entire regional network in the coupling of electricity markets, FBMC allows TSOs to allocate cross-border capacity and maximise market efficiency without jeopardising grid stability. The Amprion report clearly indicates the progress of the CWE market integration, especially with the following figures: In 2019, price convergence on the day-ahead markets increased by a further 10%, reaching 42%. In other words, in almost every second hour, day-ahead prices in the CWE have been equal because the TSOs succeeded in making sufficient power transmission capacity available to meet the demand of the entire region at the same prices.

Dr. Hans-Jürgen Brick, CEO of Amprion, comments on the positive development: “The Market Report furnishes proof that trade barriers could be decreased during the course of 2019.” Dr Brick places particular emphasis on the efficient and highly interconnected power grids in the CWE region and their “key role in ensuring Europe’s stable and secure energy system”. As regards Amprion’s individual contribution, the TSO was able to further improve the efficiency of its grid and thus strengthen European electricity trading. Whereas in 2018 the share of all active trade constraints caused by Amprion internal elements was 13.7%, in 2019 it was only 7.8%. This is due not only to the ongoing grid expansion measures, but also to the monitoring of overhead lines, which allows more efficient utilisation of the most important power lines.

Amprion has published the Market Report 2020 for the CWE region (picture: Daniel Schumann / Amprion)

> See Amprion press release, in German (html)
> Open Amprion market report (pdf, 6.97MB)
> Open Amprion market report summary, in German (pdf, 524.8kB)

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380kV line Beznau-Birr commissioned ahead of schedule


The upgrading of the existing 220kV line between Beznau in the canton of Aargau and Mettlen in the canton of Lucerne to 380kV is a key component of the “Strategic Grid 2025“, the national expansion plan for the transmission infrastructure of the Swiss transmission system operator (TSO) Swissgrid. The voltage increase ensures energy distribution and supply security in the Zurich metropolitan area, Central Switzerland, and the Swiss Central Plateau. The TSCNET shareholder has now put the first section between Beznau and Birr in Aargau into operation, one year earlier than planned.

This stretch was partly installed underground, namely across the so-called Gäbihübel near Bözberg/Riniken about halfway between Beznau and Birr. The cable laying at the Gäbihübel is the first time that part of an extra-high voltage line in Switzerland has been implemented using underground cables. Twelve cables with a weight of 30 tonnes each were installed in the conduit blocks in the summer of 2019. This was followed by the completion of the overhead line section. To connect overhead lines and underground cables, special structures were erected at both ends of the approximately 1.3-kilometre-long underground section. After a construction period of around two years, the Swissgrid control centre connected the new 380kV line to the transmission grid on 19 May 2020. The reasons for the early completion were Swissgrid’s successful project and implementation planning as well as the rather warm and dry weather.

Swissgrid is providing scientific support for the construction, commissioning, and further operation of the underground cable. Investigations are carried out, for example, on the thermal behaviour of the cable conductors depending on the current load, the temperature variation in the soil above the conduit block and in the surroundings, and the biodiversity in the soil. In May, work began on dismantling the old 220kV overhead line and restoration of the pylon sites to their original condition. The deconstruction work is expected to last until the end of 2020.

Swissgrid has put into operation the 380kV line Beznau-Birr, the first Swiss extra-high voltage line partially laid underground (picture: Swissgrid)

> See Swissgrid media release (html)

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Generation adequacy in the CWE region within standards


The Pentalateral Energy Forum (PLEF) provides the framework for regional cooperation in Central Western Europe (CWE) to improve electricity market integration and security of supply. The initiative aims to give political backing to a process of regional integration towards a European energy market. As far as the concrete implementation of impulses from the initiative is concerned, eight transmission system operators (TSOs) of seven countries cooperate in the PLEF, including the TSCNET shareholders APG from Austria, Amprion and TransnetBW from Germany, Swissgrid from Switzerland, the Dutch-German TSO TenneT, and TSCNET client Creos from Luxembourg as well as the Belgian TSO Elia and RTE from France.

The PLEF is subdivided in so-called Support Groups, e.g. covering work on market integration (SG1) and on security of supply (SG2). Within the scope of the SG2 group, the eight TSOs have worked out the third edition of the Pentalateral Generation Adequacy Assessment (PLEF GAA 3.0) and have just published a corresponding report, which summarises the main findings in 71 concise pages. The study, which examines the adequacy of electricity generation in the PLEF region up to the medium-term time horizon (2025), can be considered as significant result of TSO cooperation at regional level.

The main findings are that, under base conditions, sufficient production capacity is available, so that a breach of reliability standards is not to be expected and the adequacy of production in the CWE region will be up to standard by 2025. However, adequacy simulations have also shown that adequacy risks can occur. The electrical system may be exposed to specific situations in which the system safety is under strain. Additional unforeseen events in such situations can put even greater pressure on daily system operation, which may require the activation of special measures.

The eight TSOs cooperating in the PLEF have published their joint report on regional generation adequacy assessment in Central Western Europe

> See TenneT press release (html)
> Open PLEF GAA 3.0 Report (pdf, 2.94MB)

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€30m for substation upgrade in Lower Austria


The grid infrastructure of TSCNET shareholder APG, the Austrian transmission system operator (TSO), must comply with the changes in the power system. The APG projects in this regard are essential for the success of the energy transition and indispensable for Austria’s secure future electricity supply. One example of this is the modernisation of the Ternitz substation in Neunkirchen in Lower Austria, which was built in 1965. With its reconstruction, the TSO significantly improves the power supply of the industrial district south of Vienna, Upper Styria and the Mürztal valley in north-eastern Styria. In addition, a new phase-shifting transformer (PST) will increase failure safety for all of Austria and facilitate the smart integration of green electricity such as wind power from the Weinviertel region into the APG grid. All in all, the TSO is investing €30m in the substation upgrade.

The Ternitz substation is an important hub in APG’s supraregional power grid. Its infrastructural significance is emphasised by the new 220/110kV transformer, which will be one of three such PSTs in Austria. In the 220kV grid, it regulates the flow of electricity on the power lines in north-south direction and distributes it evenly to assure full electricity supply for the region and for all of Austria. To maintain reliability also during the time of the reconstruction, APG will be keeping the substation in operation with numerous temporary measures. Construction was originally scheduled to be concluded in December 2020, but due to the corona pandemic, completion is expected to be delayed by about three months and is now scheduled for March 2021.

Since mid-April, about 50 APG construction projects that were suspended after the Covid outbreak have been gradually resumed in compliance with the necessary distance and hygiene requirements. APG is thus living up to its responsibility not only towards the energy industry, but also as a driving force for the Austrian economy as a whole. In 2020, the investment volume of all APG construction projects in the areas of grid extension, renovation and maintenance projects will total €350m.

APG is investing €30m in the upgrade of the Ternitz substation in Lower Austria (picture: Christoph Breneis / APG)

> See APG press release, in German (html)

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Demolition makes room for DC substation


After TransnetBW, the transmission system operator (TSO) from the south-western German state of Baden-Württemberg, was granted building permit for the ULTRANET substation on the site of the former Philippsburg nuclear power plant in March 2020, the way is now finally clear for its construction. At 6.05 in the morning of 14 May 2020, the two cooling towers on the site of the former power plant were detonated. Now the necessary construction space of around 100,000m² is created. The Philippsburg plant was shut down completely on 31 December 2019 and the building construction of the ULTRANET substation is scheduled to start in the third quarter of 2020.

Since the future Philippsburg substation is the southern end point of the supra-regional high-voltage direct current (HVDC) line ULTRANET, it will be one of the most important energy hubs in Germany’s soon-to-be energy landscape. ULTRANET, a European Project of Common Interest (PCI), is jointly implemented by the two TSCNET shareholders TransnetBW and Amprion. It will transfer wind energy generated in the northwest of Germany to the more industrially developed southwest with low losses. In Philippsburg, the transmitted DC will be converted into AC and distributed regionally. In the reverse case, the substation enables the conversion of AC to DC, e.g. to transport excess photovoltaic power from the south to the north.

The fact that the “green” substation will feed renewable electricity into the transmission system instead of nuclear power is a representative of the entire German energy future. “The construction of our DC substation on the site of the cooling towers of the nuclear power plant is a visible sign and symbol of the progress of the energy transition,” comments Dr. Werner Götz, Chairman of the TransnetBW Executive Board. “In future, renewable electricity will flow from the Philippsburg site through the TransnetBW transmission grid to the entire region. Thus, as the TSO in Baden-Württemberg, we ensure that our country will have the electricity it needs even in a future without nuclear power and coal.”

With the cooling towers of the Philippsburg nuclear plant detonated, TransnetBW will begin construction of the ULTRANET substation (picture: screenshot taken from video “Sprengung der Kühltürme des Atomkraftwerks Philippsburg”, in German, YouTube channel of German newspaper “Die Rheinpfalz“)

> See TransnetBW press release, in German (html)

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First section of new 50Hertz 380kV line in operation


The 37-kilometre line section between the Stendal West and Wolmirstedt substations in the German state of Saxony-Anhalt is the southernmost stretch of an overhead line construction project, which runs for a total of over 200 kilometres from Güstrow in Mecklenburg-Western Pomerania to Wolmirstedt. With this 380kV line construction, TSCNET shareholder 50Hertz, the transmission system operator (TSO) from north-east of Germany, is successively replacing a 220kV line dating from the 50s of the last century. On 12 May, 50Hertz commissioned the Stendal West-Wolmirstedt section, whose construction costs amounted to around €40m.

In May 2019, the TSO had started erecting the 87 Pylons of this first stretch of the new transmission line, which could be installed along the entire length of the section parallel to an existing 380kv line. This continuous line bundling follows the 50Hertz planning principle of using existing infrastructure wherever possible. After the conclusion of the approval procedures, construction, and commissioning of all six sections towards Güstrow, 50Hertz will completely dismantle the old 220kV line Güstrow-Wolmirstedt.

The main objective of the 50 Hertz construction project is to improve the transmission capacity for wind power. Dr. Frank Golletz, CTO of 50Hertz, comments on the progress of the extra-high voltage line: “The increase in transmission capacity is necessary to enable us to better manage the high volume of wind energy in the northern regions of our control area and to integrate it securely into our grid. With the commissioning of this first construction phase, we have come a step closer to this target.”

50Hertz has commissioned the new 380kV overhead line between Stendal West and Wolmirstedt (picture: City of Stendal, Germany)

> See 50Hertz press release, in German (html)

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Amprion invests €1bn in 525kV cables for A-Nord


The DC transmission line A-Nord represents the northern part of Corridor A, which is one of the main axes of the German energy transition. The 300-kilometre line from the port city of Emden at the Dollart Bay to Osterath in the Lower Rhine region is being implemented by TSCNET shareholder Amprion, one of the four German transmission system operators (TSOs). With a capacity of 2GW, A-Nord will transport wind power from the North Sea to the centres of consumption in the Rhineland and Ruhr district. The southern part of Corridor A is the Ultranet line, which is being implemented jointly by Amprion and further TSCNET shareholder TransnetBW.

Like other large-scale German DC interconnection projects that are essential to the country’s low-carbon energy future, A-Nord will be realised via underground cabling. The transmission capacity of 2GW will be achieved by 525kV cables whose efficiency significantly reduces the environmental impact but requires a special insulation material and highly competent suppliers. After extensive technical tests, Amprion has now contracted the underground cables for A-Nord. The specialist companies Prysmian Powerlink and Sumitomo Electric Industries are each supplying one cable system for A-Nord. The manufacturers will produce the systems concurrently with the construction of the line, scheduled to start in 2023.

Dr Hans-Jürgen Brick, CEO of Amprion, comments in view of the challenges to achieve a sustainable energy future: “It is essential that the grid expansion continues to progress swiftly.” Dr Klaus Kleinekorte, the TSO’s CTO, adds: “With this assignment, Amprion once again demonstrates that we are a driving force for innovative developments.”

Amprion has awarded contracts for the 525kV underground cables for the A-Nord power highway (picture: Amprion / Lutz Kampert)

> See Amprion press release, in German (html)

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50Hertz turns to green financing


The grid connections Ostwind 1 and 2 to the offshore wind farms in the Baltic Sea northeast of the German island of Rügen belong to the infrastructure projects of 50Hertz, one of the four German transmission system operators (TSOs), which contribute to a sustainable European energy future. Ostwind 1 is already in operation and connects the wind farms “Wikinger” and “Arkona” via two offshore platforms with the Lubmin substation in the Bay of Greifswald. The Ostwind 2 project will connect the nearby wind farms “Arcadis Ost 1” and “Baltic Eagle” to the German extra-high voltage grid. The future transmission capacity of both connections is approximately 1.5GW.

To financially secure these forward-looking projects, the TSCNET shareholder is now active on the green investment market as corporate issuer of Green Debt: On 6 May 2020, Eurogrid GmbH, the parent company of 50Hertz, has issued its first Green Bond in the amount of €750m on the regulated market, thus securing the liquidity for the two offshore projects and further grid expansion necessary for the energy transition.

Marco Nix, CFO of 50Hertz, comments on the bond issue: “With the first Green Bond in our company’s history, we are securing part of the necessary investments in the grid infrastructure over the next few years.” Especially in view of the current difficult economic circumstances, the great interest of the financial markets in the bonds was proof of the confidence in the TSO’s sustainability strategy and investment plans. “The transaction is an important cornerstone in driving forward the expansion of our grid and thus the energy transition,” adds Marco Nix.

50Hertz has successfully issued its first Green Bond in the amount of €750m (picture: 50Hertz)

> See 50Hertz press release (html)

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