The Kontek HVDC link between Denmark and Germany

The Kontek HVDC cable link connecting Denmark and Germany has been in commercial operation since 1996 and with a total length of 172 km and a transmission capacity of 600 MW at 400 kV, the cable link is still unique worldwide. In addition, the 120 km of land cable is the world´s longest continuous length of underground cables for HVDC application. The objective of this grand project was to open up the possibility of exporting electrical power from efficient Danish power generating stations, combined with having the transmission possibilities between Sweden and the eastern part of Germany. A decision was made in 1992 to establish a 600 MW High Voltage Direct Current (HVDC) Connection between the two countries. For the Kontek link the selected cable was the unique flat type cable supplied by the Danish company NKT Cables. Both 400 kV underground and submarine cables are manufactured in NKT Cables´ plants, having upgraded the design and technique of the unique flat type cable for the higher transmission and voltage level required for the KONTEK link. Consisting of a total of 120 km the land cable represents the longest continuous section of HVDC underground cable in the world. The link includes a 106 km long two-core HVDC underground cable from the Danish converter station to the Danish coast, followed by a 52 km section of flat type armoured cable under the Baltic Sea. On the German side the connection continues with a 14 km land cable to the converter station at Bentwisch