financing large offshore wind farms, one of which is improved turbine access systems for technicians and equipment in heavier seas.
The OWA access competition seeks to identify and develop new access systems that increase the weather window for turbine availability and the safety of those being transferred. The competition has selected designs in three categories: vessels, transfer systems, and launch and recovery systems.
Some of the six vessel designs chosen in this category include transfer system designs: the TranSPAR craft, the Windserver, the Nauti-Craft, and the Pivoting Deck Vessel. These four designs would transfer personnel and equipment from vessel to turbine with potential motion compensation technology and include the Autobrow, the BMT and Houlder Turbine Access System Mark II, the Momac Offshore Transfer System, and the Wind Bridge. The launch and recovery systems include designs from three companies and establish bases or mother ships for dispatching and recovering craft from sea.6 Each of these designs offers the potential for reducing risk in transferring personnel between vessels and turbines, although each design is likely to have its own strengths and weaknesses. Because site conditions and equipment at offshore wind farms can vary, attempting to mandate one design over another might be difficult.
The committee is unaware of any U.S. regulations directly addressing access by boat or the transfer of personnel between a vessel and an offshore structure. While SOLAS offers basic safety principles for pilot transfer, most guidance on the transfer of personnel is provided by industry best practices or by guidelines from groups such as IMCA and RenewableUK. Technology in this area is evolving rapidly, and development of U.S. regulations or standards could be difficult. The transfer of personnel, therefore, could benefit from a performance-based rather than a prescriptive approach.
6 More information concerning each of these designs is available at http://www.carbontrust.com/media/105302/owa-access-bg-29may2012.pdf.