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BorWin5

BorWin5 is the fourth project that TenneT is implementing off the coast of Borkum using extra-high voltage direct current transmission technology, in addition to the BorWin1, BorWin2 and BorWin3 projects.


Location
Niedersachsen, Nordsee
Type
Offshore
Category
offshore
Status
planning
Tags
  • BorWin 5
borwin5

About the project

230 kilometres long and 900 megawatts strong direct current connection

BorWin5

BorWin5 has a total length of approx. 230 kilometres. The starting point will be the converter platform BorWin epsilon in the North Sea. There, the three-phase current generated by the wind farm at sea will be converted into direct current and transported to the mainland with an approximately 110 kilometre long sea cable. From the landfall in Hilgenriedesiel, the electricity will be transmitted along 120 kilometres of underground cable to the future converter station Garrel/Ost in the Cloppenburg area.

As with most offshore grid connection systems for wind farms in the western North Sea, the cable route of BorWin5 also runs across the island of Norderney. In order to protect the sensitive natural area in the Lower Saxony Wadden Sea National Park and to ensure dike safety, TenneT has drilled horizontally on the island, into which cable protection pipes have been inserted. The sea cables are then pulled into these pipes as part of the cable laying process.

Connecting concept:

BorWin5 is one of the offshore grid connection systems, which TenneT connects directly to the corresponding wind turbines via 66 kilovolts three-phase alternating current (AC) cables. Hence, a transformer station that was previously necessary in each wind farm is no longer needed. Furthermore, 155 kV AC cables are no longer required to connect TenneT's offshore platform to that of the wind farm. This means that the electricity generated at sea is directly fed into the TenneT converter platform. The conversion of AC into direct current (DC) takes place at the converter station. The electricity is transported by submarine cable to shore and then by underground cable to the onshore converter station, where it is converted back into AC and fed into the extra-high voltage grid. Economically speaking, this innovative technology leads to enormous cost savings.

Impressions

  • BorWin5 HDD Norderney

    The connection runs across the island of Norderney. To protect sensitive areas, horizontal boreholes are being drilled there in the north and south of the island

  • BorWin5 HDD Norderney

    The connection runs across the island of Norderney. To protect sensitive areas, horizontal boreholes are being drilled there in the north and south of the island

  • BorWin5 HDD Norderney

    The connection runs across the island of Norderney. To protect sensitive areas, horizontal boreholes are being drilled there in the north and south of the island

  • BorWin5 HDD Norderney

    The connection runs across the island of Norderney. To protect sensitive areas, horizontal boreholes are being drilled there in the north and south of the island

  • BorWin5 Surface Converter Garrel

    The onshore converter is being built in Garrel/Ost from 2022

Contacts

cornelia junge.jpg

Cornelia Junge

Spokesperson - Project Communication Offshore

Further information