The transmission grid between the Eula substations near Leipzig (Saxony), Weida (Thuringia) and Herlasgrün (Saxony) in the Vogtland region and the search areas of Hof and Marktleuthen/Kirchenlamitz in Bavaria is facing a generational change. The existing 220 kV overhead line from Eula to Herlasgrün will be replaced by a powerful 380 kV overhead line (replacement construction). From Herlasgrün to the search areas of Hof and Marktleuthen/Kirchenlamitz, a new 380 kV line will be built – also as an overhead line.
50Hertz is implementing the Eger-Elster overhead line project to the state border of the Free State of Saxony with the Free State of Bavaria. The transmission system operator TenneT is responsible for the project developer for the section from the Bavarian border to the Marktleuthen/Kirchenlamitz search area in Bavaria. Accordingly, the project links the control areas of the two transmission system operators 50Hertz and TenneT. This means that it is a so-called interconnector.
The future Eger-Elster line serves to increase transmission capacity as well as regional and national security of supply. The existing 220 kV line is getting on in years and also has too little transmission capacity for the transmission tasks to be expected from the expansion of renewable energies. For this reason, 50Hertz is planning to convert to the modern voltage level of 380 kV and to increase the current-carrying capacity to 4,000 amperes. This involves modernisation of the connected substations and transformers. The existing 380 kV lines between Thuringia and Bavaria also have unacceptably high capacity utilisation. There is therefore a need for the construction of a new 380 kV overhead line in section south.
In the future, the Eger-Elster line with its increased capacity will also make an important contribution to the energy transition in order to feed regionally generated electricity from renewable energies into the extra-high-voltage grid and transport it to the demand regions in the south. Due to the expansion of renewable energies in Thuringia, Saxony and Bavaria, there is an increasing need for capacities for feed-in from the local distribution grid. In addition, the line contributes to the reduction of redispatch costs.2
The replacement construction in the north and middle sections follows the NOVA principle (grid optimisation before reinforcement before expansion) and is therefore classified as grid reinforcement. The south section is a new building.
The commissioning of the Eger-Elster pipeline will take place in sections and is scheduled for 2037. To ensure supply, the old pipeline must remain in operation until the new pipeline is commissioned.