Partial undergrounding of overhead lines at sensitive sections

Project description

Amprion operates a transmission grid of about 11,000 km to enable the transmission of electricity for more than 29 million people across an area from Lower Saxony down to the Alps. While the majority of its HV routes comprise overhead lines, at certain environmentally sensitive sections Amprion is taking the route underground.

Customer challenges

• As part of the 'Energiewende', German TSO's, such as Amprion, need to upgrade their high voltage power transmission networks to transport electricity generated by wind farms in the north over long distances to the main areas of consumption in the south.
• Amprion wants to take a key section of its 400 kV transmission network underground

Nexans solution

• Nexans is playing a key role in this project by supplying cables that will enable Amprion to take its overhead lines underground at sensitive sections of the route.
• Nexans was involved in Amprion’s pilot partial undergrounding project at Raesfield, and is now supplying 31.8 km of 400 kV cable for a major project at Legden on the route between Wesel and Meppen. The 5.2 km Legden route is made up of 2.1 km of tunnel and 3.1 km of pipes. Nexans is supplying the cable for one double circuit with a 2500 mm2 copper cross-section. The section of cable installed in the tunnel will feature a halogen-free flame-retardant (HFFR) sheath and Nexans is also providing the steel support structures.
• Delivery of the cables is scheduled for July 2022, with installation completed in 2023