Underground cable replacement of the KONTEK cross-border 400-kV grid connection
The KONTEK 400-kV grid connection, KONTEK for short, is a direct current connection between the German and Danish power grid. The name KONTEK comes from the word “continent” (“Kontinent” in German) and the name of the Danish grid operator Elkraft (now Energinet), which used to be abbreviated as ‘ek’ and operates the power grid on the Danish islands of Lolland, Falster and Seeland. 50Hertz is responsible for KONTEK on the German side. This high voltage direct current (HVDC) transmission line is operated at 400 kilovolts (kV) and transmits 600 megawatts (MW). KONTEK is about 170 kilometres long and was put into operation in 1995. The HVDC cable runs through a so-called point-to-point connection via underground and submarine cable, directly between the converter or transformer stations of both countries. This direct connection transports the energy with fewer losses and is therefore more efficient for everyone.
25 years later, the cables had reached the end of their operability. The 150-km long onshore and submarine cable section, for which Energinet is responsible, was replaced first. The underground onshore cable over a further distance of around 15 km in Mecklenburg-Western Pomerania was replaced by 50Hertz during the second stage. After the new route has been commissioned, the old line will be disassembled.
After the conclusion of the work activities, KONTEK has been operational again since mid-2023.