There will be a six month delay to the installation of the SylWin1 offshore converter platform, a Siemens spokesperson told Windpower Offshore today. Geotechnical investigations have revealed a previously-undetected soft soil layer that means the convertor platform’s base frame must be anchored to a depth of 100m, rather than the originally-planned 70m.
Initial seabed investigations for the SylWin1 project prompted Siemens to plan on a 70m anchoring depth. More detailed geotechnical work, in part undertaken to search for remaining Second World War munitions, revealed the soft soil deposit and the need to anchor more deeply.
"We immediately undertook measures to accelerate the work," said the Siemens spokesperson, adding that the convertor platform’s base will be installed by September. Installation of the topside will not begin before May 2014 at the earliest.
Once the topside commissioning has been completed, a two-four month test is generally conducted by the transmission system operator, TenneT, before commercial operation begins.
The SylWin1 platform will convert alternating current (AC) electricity from the DanTysk, Butendiek and Sandbank offshore stations (each with a 288MW capacity) to direct current (DC) for transmission to the onshore electricity network.
DanTysk is the most likely of the three offshore wind farms to be affected by this delay. Earlier this month, the first foundations and transition pieces for the project, owned by Vattenfall and Stadtwerke München, were loaded onto Seafox 5 for transport to the site west of Sylt .
Siemens has set aside reserves of €598m to the end of the first quarter of 2013 to cover additional costs associated with its four German offshore transmission system projects: HelWin1, HelWin2, BorWin2 and SylWin1. The money has been earmarked for things such as the redesign of converter platforms, additional materials and penalties for late completion of projects.