The mission equipment for monopile handling remains the critical path to the vessel being operational for foundation monopile installation. The main elements of this equipment commenced transport from China at the end of 2022. Seaway Alfa Lift will head to Europe, where the mission equipment will be completed and commissioned.
The semi-submersible vessel is a custom design by Ulstein. The design combines the benefits of a semi-submersible transport vessel with a large, 3,000 mt lifting capacity main crane. She can perform heavy lift crane operations with the main deck submerged.
Offshore wind services
She will be working in the early development stage of new offshore wind farms, starting with the Dogger Bank A and B Wind Farms in the UK North Sea, at which she is expected to commence work in 2024.
The vessel's capabilities match the future requirements of the offshore wind industry, allowing her to transport and install up to 10 x 1,500t ultra-large jacket foundations or 11 x 2,000t XXL monopiles plus transition pieces for the largest anticipated Wind Turbine Generators.
The 'Seaway Alfa Lift' can install all types of bottom-fixed offshore wind foundations and will also transport and install topsides and subsea modules, in addition to other heavy cargoes within oil and gas.
Capacities in detail
The vessel's crane has a maximum lifting capacity of 3,000 tonnes at 30 metres and 1,000 tonnes at 76 metres outreach. The 216.3-metre vessel will also have a 10,000+ m² "smart deck" that can carry up to 14 giant monopiles per trip and will be fully submersible to a depth of 14.66 metres.