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Energy transition milestone project goes live: South-West Interconnector fully operational

South-West Interconnector creates significantly more transport capacities along the north-south axis and reduces load on power grid

Energy transition milestone project goes live: South-West Interconnector fully operational
  • 380 kV line project from Saxony-Anhalt via Thuringia to Bavaria now fully operational
  • South-West Interconnector (Thuringian Power Bridge) creates significantly more transport capacities along the north-south axis and reduces load on power grid
  • Higher transport capacity an essential precondition for the nuclear power phase-out
  • Dr. Reiner Haseloff, Minister-President of Saxony-Anhalt, gives switching command to put line into operation

Berlin – Another feat accomplished: after more than ten years of planning, approval procedures and construction, the South-West Interconnector, running from Bad Lauchstädt (Saxony-Anhalt) via Erfurt-Vieselbach and Altenfeld (Thuringia) to Redwitz (Bavaria), has finally reached its full potential with today’s commissioning of the second electrical circuit. The first electrical circuit was already put into operation in December 2015. The 380 kV power line, also known as the Thuringian Power Bridge, was declared a European priority project by the EU and is a key element of the Power Grid Expansion Act (EnLAG). It is now the second line connecting the north-east of Germany to Bavaria, achieving a considerable reduction of the load on the formerly only connection between Remptendorf in Thuringia to Redwitz in Bavaria. Both systems or circuits of the South-West Interconnector, with its total length of almost 200 kilometres (161 km in the 50Hertz grid area, 31 km in the TenneT grid area), can now boast a transmission capacity of about 5,000 megawatts (MW). 50Hertz invested about 320 million EUR in this extra high voltage line.

The official switching command for today’s activation of the line was given by Dr. Reiner Haselhoff, Minister-President of the state of Saxony-Anhalt, from the 50Hertz headquarters in Berlin to the 50Hertz control centre in Neuenhagen bei Berlin. According to the Minister-President, the commissioning of the South- West Interconnector and the grid expansion in general are of vital interest for Saxony-Anhalt. “Our federate state, with its large amount of installed capacity of wind and solar power, is a pioneer regarding the energy transition,” says Haseloff.

Boris Schucht, 50Hertz’s CEO, stressed that today’s completion of the South- West Interconnector is a good day for the energy transition: “With this line, the integration of electricity generated from renewable sources in the north-east of Germany is improved considerably. Furthermore, this substantially higher transmission capacity is an essential precondition for the nuclear power phase-out, as more electricity can be transported from the high-output north-east to the highconsumption south. The line will also ensure that the costs for congestion management can stay stable”, said the head of 50Hertz.
About 80 per cent of the redispatch costs incurred by 50Hertz in the past were due to the bottleneck situation on the sole interconnector between the 50Hertz area and Bavaria (i.e. the 380 kV line from Remptendorf to Redwitz). The commissioning of the first of now two circuits on the South-West Interconnector in late 2015 allowed congestion management savings of about 80 million EUR in the following year. “This clearly shows that grid development works”, stated Schucht regarding these savings.
He also referred to the capacities of renewable installations in the northern and eastern part of Germany, which will continue to grow in the years and decades to come. “Just as everywhere in Germany, grid development in our region is therefore still ongoing. This is apparent from the Federal Requirement Plan Act as well as the grid development plans. Nevertheless, with today’s completion of the South-West Interconnector, we have now achieved an important objective and reached a milestone in the implementation of the energy transition.”

50Hertz’s CTO, Dr. Frank Golletz, expressed his thanks to both Saxony-Anhalt and Thuringia for their constructive assistance during the implementation of this project: “In Thuringia, which was particularly affected by two of the three line sections, there was already a great deal of protest, even if intermittent, against the South-West Interconnector some years ago. Legal proceedings were also instituted before the Federal Administrative Court in 2012, but only confirmed the legality of the planning approval decision by the Court of Leipzig in 2013. All this shows that a few hurdles needed to be taken to realise this project.”

At the same time, the company went through a significant learning curve, as errors were made in the communication to local citizens during the initial phase of the project. “Today we know that we have to approach citizens and all other stakeholders much more extensively and especially at an earlier stage to provide them with information on such projects in a transparent manner and in the form of dialogue. We also need to pay closer attention to local concerns as well as consider tips and suggestions. Today, these principles are standard for 50Hertz, as we have learned in the past, also and particularly during this project.”

Background information:

The South-West Interconnector was realised in three line sections. Line section 1 starts at the Lauchstädt substation near Halle (Saxony-Anhalt) and ends at the Vieselbach substation near Erfurt (Thuringia). The 2nd line section connects Vieselbach and Altenfeld. From there on out, the 3rd line section runs through the Thuringian Forest up to the state border with Bavaria.

The 1st line section between Lauchstädt and Vieselbach, which has been operational since December 2008, follows an existing 220 kV line and the ICE railway for most of its length, which totals 78 kilometres.

The route of the 56 km 2nd line section between Vieselbach and Altenfeld follows the infrastructure lines of the 380 kV line from Mecklar to Vieselbach, the A71 national highway and the ICE railway section up to Altenfeld in accordance with the bundling principle. From Vieselbach, the overhead line route runs westward and northward, parallel to the existing overhead line Vieselbach-Eisenach/Mecklar, until it reaches national highway A71, where it heads south along the highway and the ICE railway between Nu¨rnberg and Erfurt, up to Altenfeld. From Traßdorf on, the towers of the new 380 kV line are also used for the 110 kV line between Stadtilm and Altenfeld over a distance of 20 kilometres. Its own route arrives there from the east, coming from the Stadtilm substation. Two sections of a 110 kV overhead line of the railway company are also supported by the towers of the South-West Interconnector over a total distance of about 10 kilometres.

For the 3rd line section between Altenfeld and the Thuringian state border, the first detailed route planning was available in the first half of 2013. This planning was based on the route corridor from the regional planning procedure, confirming that the route would closely follow the ICE railway. With its total length of 26 km, the corridor will run from the Altenfeld substation up to the northern entrance to the Singertal, running closely parallel to the existing 380 kV line, in the direction of Goldisthal. At the Bleßberg mountain, the corridor continues to Schalkau and the interconnection point at the state border with Bavaria. At this point, TenneT TSO GmbH, the transmission system operator responsible for Bavaria takes over the line circuits and extends them to Redwitz.

Authorisation procedure

Project status 1st section (Lauchstädt - Vieselbach)
The first section was put into operation in 2008 after two and a half years of construction. The overhead line is located on the territories of Saxony-Anhalt and Thuringia. As a result, the mandatory procedures are carried out by two state authorities. For the permit section in Saxony-Anhalt, the state planning assessment of the regional planning procedure was concluded in November 2005. The planning approval decision followed in November 2007. For the permit section in Thuringia, the regional planning procedure was concluded with the state planning assessment in December 2005. The planning approval decision was made in December 2007. In February 2006, work commenced in Steigra (Saale district, Saxony-Anhalt).

Project status 2nd section (Vieselbach - Altenfeld)
Since 2 July 2015, the 2nd line section between Vieselbach and Altenfeld has been operational. The competent authority for the spatial planning and planning approval was the Thuringian Administrative Office in Weimar. In March 2007, the regional planning procedure with the state planning assessment for the planned corridor was concluded. The planning approval decision was made in January 2012. An action against the decision of the Thuringian Administrative Office was rejected by the Federal Administrative Court in Leipzig in July 2013. After a pause in the construction activities due to official procedures, the 2nd line section was constructed by June 2015.

Project status 3rd section (Altenfeld – Thuringian state border)
On 17 December 2015, the first electrical circuit of the 3rd line section was put into operation, signalling the start of electricity transport via the South-West Interconnector to the Redwitz substation in Bavaria. The second electrical circuit was activated on 14 September 2017. For the regional planning procedure, the state planning assessment was finished in March 2011. On 21 January 2015, the Thuringian Administrative Office issued its planning approval decision. The plan approval procedure was officially initiated by the Thuringian Administrative Office on 19 September 2013. Between 7 October and 18 November 2013, the planning documents were available for consultation at the administrations of the cities and municipalities involved, as well as made available online by 50Hertz. Public agencies and other authorities were able to communicate their expert position on the project between 27 September and 17 December 2013. A total of 188 objections by citizens and environmental associations or positions of public agencies and other authorities was received by the Administrative Office of Thuringia. For the section between the Bavarian state border and Redwitz, Tennet is the competent transmission system operator.

Construction and operation

Since 17 December 2015, the South-West Interconnector has been in trial operation.

1st line section (Lauchstädt – Vieselbach)
The first and longest section (78 kilometres and 197 towers) of the South-West Interconnector between the substations of Lauchstädt in Halle and Vieselbach near Erfurt has been operational since 2008.

2nd line section (Vieselbach – Altenfeld)
Construction on the second section (56 kilometres and 170 towers) between the substations Vieselbach and Altenfeld started in 2012. The section underwent trial operation from early July 2015 to mid-December 2015 and was released for permanent operation on 17 December 2015.

3rd line section (Altenfeld – Thuringian state border)
Construction on the third and shortest section, from Altenfeld to the state border between Thuringia and Bavaria (26 kilometres and 78 towers), started in January 2018. Since 17 December 2015, the first electrical circuit of this section has been in trial operation. Since 14 September 2017, the second circuit of the South-West Interconnector has also been operational.

You can find the press release and a 2:30 minute video on the South-West Interconnector project under https://www.youtube.com/watch?v=H-oNpcTbbVg 

Press release as PDF-File

For further information, please contact:
Volker Kamm, 50Hertz Transmission GmbH, phone 030-5150-3417, fax 030-5150-2199, mobile 0172-3232-759, volker.kamm@50hertz.com

Press Contact

Volker Kamm


Volker Kamm
Tel: +49 (0) 30 5150-3417
Fax: +49 (0) 30-5150-2199
E-Mail: volker.kamm@50hertz.com