Amprion: Expansion and Conversion of the Hanekenfähr Substation
The authors are Till Ruland and Heiner Dokters. Mr. Ruland is Project Manager Civil Engineering and Roadway Construction at Bernhard Heckmann GmbH & Co. KG construction company. Mr. Dokters is Head of Business Unit Energy Solutions at egeplast international GmbH. This article was recently published in our egeNews.
In the course of the Energiewende, the energy landscape in southern Emsland is changing. At the Hanekenfähr site, the Emsland nuclear power plant will be taken off the grid at the end of 2022. At the same time, increasing amounts of wind energy from the north must be sensibly integrated into the grid. This is why at the Amprion substation Hanekenfähr DolWin4 and BorWin4 offshore grid connection systems will be connected to the transmission grid in 2028 and 2029. Amprion is taking this change into account with extensive work at the substation Hanekenfähr. A key measure here is the installation of two phase-shifting transformers, which will enable better control and optimization of power flows. As part of a so-called site clearance, some overhead lines had to be dismantled and installed as underground cables.Partly trenchless with undercrossing of a railroad line, egeplast Power Protect PE-RT conduits for high and extra-high voltage cables with low-friction inner layer and individual marking were installed.
Project report: Laying of a cable conduit system for high-voltage cables
Lingen (Emsland) is a city which traditionally has had a reputation as a significant energy location in the southern Emsland district. At present, the Emsland nuclear power plant, which will be taken off the grid at the end of 2022, still continues to feed 1.4 GW into the grid in Amprion’s Hanekenfähr substation. At the same time, the integration of wind power is gaining increasing importance at the Hanekenfähr site. In 2028 and 2029, this is where Amprion will commission the two offshore grid connection systems, DolWin4 and BorWin4. Prior to that, the Hanekenfähr substation will undergo extensive expansion and remodelling, including the installation of two phase-shifting transformers and the expansion of facility by several switch panels. This step requires some land clearing by means of cabling multiple overhead lines. This is realised in two construction phases as an underground cable system:
1st construction phase: Installation of a new 110-kV high-voltage threephase current connection via an underground cable
This connection consists in two 110-kV-systems with three 110-kV underground cables each (connection of the 0922 “Rühle-Ost” and 1502 “Hanekenfähr-Holthausen” circuits) and leads from Hanekenfähr to the 1110 cable lifting mast. The first segment involved an underpass of the railway tracks connecting Münster and Norddeich using the pipe jacking method for DN 1,200 mm covering a tunnel length of approx. 100 meters. Subsequently, two cable conduit bundles including the relevant tracer pipes were inserted into the jacking pipe. For the second segment, which was approx. 700 meters long, the open-trench method was applied. For this purpose, egeplast Power Protect PE-RT protective layer pipes for high-voltage and very high voltage pipes featuring a low-friction internal layer and individual identification were used to guarantee a correct connection to the supply system in question along with the subsequent insertion of the underground cables, as civil engineer (M.Sc.) Till Ruland from Heckmann Bau explains: “Here, the high degree of precision required when inserting the pipe bundles into the DN 1,200 mm jacking pipe under very confined space conditions represents a major challenge. In this case, a suitable system solution for cable protection pipes is indispensable”.
2nd construction phase: Preparation of 110-kV- and 220-kV-underground cable routes
The expansion of the Hanekenfähr substation involved previous land clearing operations, which in turn required reverting to underground cables for the existing 110-kV and 220-kV-overhead lines. The line routes run in the pre-existing North-South axis across the facility, south of the existing Hanekenfähr substation as well as west of its extension. The installation was carried out in the form of underground cables applying open-trench installation and egeplast Power Protect PE-RT protection layer pipes for high- and very high voltage cables. The excavation and pipeline works were performed by a consortium consisting of Bernhard Heckmann GmbH & Co. KG Bauunternehmen, Knoll GmbH & Co. KG and Sonntag Baugesellschaft mbH & Co. KG. As civil engineer (M.Sc.) Till Ruland commented on the cooperation: “Timely completion of construction projects of this kind absolutely requires a supplier providing a high-quality production range and service quality. egeplast has had many years of experience with handling projects of this type and once again was characterised by significant supply flexibility and excellent service. With regard to construction, we are right on schedule and will be able to complete this project in due time.”
Project data Hanekenfär
110 kV / 220 kV AC cable; Hanekenfähr substation
Installation of a cable protection system for 110 kV or 220 kV high-voltage AC transmission
525 kV / Application of egeplast Power Protect PE-RT cable protection duct system providing increased heat stability for high- and very high voltage cables for up to 525 kV
Open-trench and trenchless construction (pipe jacking DN 1,200 mm)
4.800 m Power Protect PE-RT d 200 x 11,9 mm (with low-friction inner layer and individual color coding of stripes)
5.060 m Power Protect PE-RT d 200 x 11,9 mm
13.320 m Power Protect PE-RT d 250 x 14,8 mm (electrofusion couplers)
Parties involved in the project
Client: Amprion GmbH
Planner: Ingenieurbüro H. Berg & Partner GmbH
Installer: Arbeitsgemeinschaft Bernhard Heckmann
GmbH & Co. KG Bauunternehmen, Knoll GmbH & Co. KG, Sonntag Baugesellschaft mbH & Co. KG
egeplast Power Protect PE-RT Protective pipe for high and extra high voltage cables
The egeplast Power Protect PE (former ege-com®Macroduct High-T) is a protective pipe made from polyethylene, which is used for high and extra high voltage cables up to 525 kV. The protective pipe has an increased thermal stability due to a special PE-HD material, in order to withstand high thermal loads for a long period of time. Due to this the electricity distributors can ensure a long service life of their grid.
Author contact details
Telefon: +49 2381 7990-737
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