German TSO seeks export cable system provider

German transmission system operator (TSO) 50Hertz has issued a contract notice seeking a submarine and land cable system for the OST-6-1 offshore wind grid connection in the Baltic Sea.

The contract covers the design, engineering, construction, supply, installation, burial, handling, and commissioning of the 220 kV submarine and land cable systems from the onshore substation i.R. Gnewitz to the two offshore substations in the Gennaker offshore wind farm within the 12 nautical mile zone of the Baltic Sea.

The project is divided into two lots. Bidders have the option to bid for both lots and may receive awards for both lots.

The OST-6-1 Lot 1 West is for the production, transport, and installation of two HV electrical grid connection systems, including ancillary systems, accessories, and parts for the cable systems between offshore substation West and the onshore Substation i.R. Gnewitz with a total route length of approximately 71 kilometres per cable system or 142 kilometres in total length. Each route consists of approximately 33 kilometres of onshore cable route, and 38 kilometres of offshore cable route.

In addition, certain cable design engineering services are to be performed by the most economic bidders prior to award for a fixed sum for each lot as described above.

The OST-6-1 Lot 2 East is for the production, transport and installation of one HV electrical grid connection system including ancillary systems, accessories and parts for the cable system between the offshore substation East and the onshore substation i.R. Gnewitz with a total route length of approximately 88 kilometres, consisting of approximately 33 kilometres of onshore cable route and 55 kilometres of offshore cable route, and one HV by-pass system including ancillary systems, accessories and parts for the cable systems between the offshore substation West and the offshore Substation East with an approximate route length of 21 kilometres.

Again, certain cable design engineering services are to be performed by the most economic bidders prior to award for a fixed sum for each lot as described above.

The tender remains open until 25 November.

The OST-6-1 offshore grid project will connect the 927 MW Gennaker offshore wind farm, being developed by Skyborn Renewables (formerly wpd offshore), a subsidiary of Global Infrastructure Partners (GIP).

The installation of the 103 Siemens Gamesa 9 MW wind turbines and the commissioning of the offshore wind farm is expected to be completed in 2026.