The German transmission system operators (TSOs) are legally required to develop the necessary infrastructure for making wind farm development possible. TenneT Offshore GmbH’s merger with Transpower (previously E.ON Offshore Netz GmbH) has made it the first cross border electricity transmission operator in Europe. Its focus it to develop the north-western European energy market and to integrate sustainable energy.
Lloyd’s Register has been involved in several projects for developing the infrastructure elements required for bringing wind based electric energy to the German main grid.
In connection with the design of a new offshore HVDC platform off the coast of Germany, we were engaged by Aibel to perform a hazard identification (HAZID) of the platform design, including preliminary qualitative risk evaluation. The DolWin2 HVDC platform with connection to shore is one of TenneT's projects. Aibel is a sub-contractor of ABB and has the contract for delivery of a complete installation to TenneT.
The purpose of the HVDC platform is to convert AC current to DC and transmit electrical power to shore. The platform features AC/DC converter systems, including HV switchboards, HV transformers, shunt reactors, converter reactors and valves, as well as auxiliary systems. In addition to the HVDC platform, the DolWin2 project includes a number of wind farms that will deliver to AC platforms, interfield cables, main DC cables to shore and an onshore converter station.
Alpha Ventus and BorWin1
We carried out Reliability, Availability and Maintainability (RAM) analyses and risk assessments regarding the availability for the offshore platform, cable connection to shore and the onshore station for these grid connection projects. These installations are already completed and the studies have been prepared for the operational phase.
Due to a very "crowded" German sector, a number of existing pipelines and cables have to be crossed by the cables bringing wind power to shore. We have assisted in establishing cable crossing agreements for the subsea cables in connection with the Alpha Ventus, BorWin1, BorWin2 and DolWin1 projects.