In August Vattenfall and Stadtwerke Miinchen (SWM) reached an investment agreement for the Sandbank offshore wind project, with an investment value of approximately €1,2bn, to be built 90km west of the island of Sylt. A special project company, Sandbank Offshore GmbH, is set up for this purpose whereby Vattenfall holds 51% and SWM 49% of the shares. Sandbank will have 72 turbines installed in an area covering around 21 km2, in water depths between 25 and 37m.
This was shortly followed by the announcement of the main contracts. Siemens will be supplying 72 of the latest from their G4 platforms, the SWT-4.0-130 turbine. Danish manufacturer Bladt Industries won an EPCI contract for the for the fabrication of the offshore substation. The company will work together with Semco Maritime and ISC on this substation which will consists of a 2,000t topside with 2 transformers and a helideck on a 1,500t 4-legged jacket foundation and is planned to be ready for transport in the 2nd quarter of 2016. VBMS received the contract for the supply, installation and related activities of 76 inter-array cables. The cables and additional accessories will be provided by JDR from their manufacturing site in Hartlepool.
Construction of Sandbank is planned to start in the summer of 2015 with the installation of the monopile foundations, for which EEW Special Pipe Constructions GmbH was contracted earlier this year. Engineering company Bilfinger will be responsible for the installation for which it signed a contract with Swire Blue Ocean to provide the installation vessel. MPI Offshore are contracted to install the turbines, using their MPI Adventure.
Sandbank will be connected to the SylWin offshore converter station. When in full operation, planned for 2017, the 288MW wind farm will be generating enough energy to power around 500,000 households annually.
The two companies work also together on the at 20km further located DanTysk wind farm which is nearing completion at the moment. Siemens will be responsible for the operation and maintenance of both wind farms for at least the first 5 years. A new service concept will be used whereby both wind farms will be serviced from a Service Operation Vessel which holds workshops and accommodation for around 30 technicians. This vessel will be permanently positioned between the wind farms from where technicians can access the turbines and be transferred back and forth to shore by ways of helicopter.