BorWin4 & DolWin4 – South Section: Expansion of the Green Power Grid Progresses

In the southern Emsland region, the expansion of the green power grid is entering a significant phase: Amprion will enable the grid connection to BorWin 4 & DolWin 4 by 2028 with the construction of a 12 km long DC connection from Wietmarschen to Lingen (Ems). The egeplast Power Protect PE-RT cable protection pipe system is being used, parts of which were laid using the environmentally friendly HDD method.

Amprion Offshore GmbH commissioned the ARGE Tief4 BD4 LA Süd consortium, consisting of Knoll GmbH & Co. KG, Bernhard Heckmann GmbH & Co. KG, Depenbrock Bau GmbH & Co. KG, and Sonntag Baugesellschaft mbH & Co. KG, to execute the construction project starting in summer 2024. Amprion chose the egeplast cable protection pipe system, which features increased thermal stability and is suitable for high and extra-high voltage cables up to 525 kV with various connection techniques (double socket, electrofusion socket, Golden Seam) and transition pieces.

Static Calculations as a Service

Due to the nature of the soil, open trenching was used for long stretches. However, individual sections could also be laid using the cost-efficient and environmentally friendly HDD method. A particularly complex section involved the undercrossing of the Dortmund-Ems Canal, the Ems River, and a Fauna-Flora-Habitat (FFH) area, a protected nature and landscape area, in the Lingen Hanekenfähr region. The HDD bore, with a length of approx. 1,100 m (6 strands), was changed from SDR 11 to SDR 7.4 based on the tensile force calculation. A particular challenge here was primarily the advancement of the pipes in the difficult-to-access terrain in the forest. This required extensive site clearance measures in advance.

Especially for complex drillings like these, precise planning, good communication, and collaboration between the construction company and pipe manufacturer are essential. Sven Vaske, overall project manager for ARGE Tief4 LA Süd, rates the exchange as consistently positive: “egeplast consistently supported us with its technical expertise during work preparation to enable the most effective construction process possible.” These consulting services by egeplast included, among other things, static calculations for the construction and operating conditions, so that the completion of the South section is planned for December 2025.