Seaway 7
Specializes in offshore wind and subsea infrastructure installation, including cable-lay and burial operations.
Seaway7 is a marine contractor focused on the delivery of offshore wind projects for developers in Europe, Taiwan and the US. Its offshore experience in the energy sector spans three decades and covers over 50 completed projects, transferring knowledge gained in the oil and gas industry into the offshore fixed wind market. The company has been active in offshore renewable energy since 2009, when it installed its first wind turbine generator monopile foundation offshore in the UK, and it reports having installed over 800 wind turbine generator foundations, 30 substations and 2500km of inner array cables. Contracting comes in three shapes: stand-alone transport and installation of foundations, or cables, or wind turbines; integrated projects combining more than one of those scopes; and EPCI solutions in which Seaway7 manages design, procurement and fabrication to deliver a full project solution. Cable work covers submarine cable and subsea umbilical installation, repair and maintenance, spanning inner-array grid cables and export cables, with cable trenching performed by a trenching ROV housed aboard the cable lay vessel Seaway Aimery, which carries two under deck turntables giving a capacity of 4,250 tons of cable. Related cable services include marine cable route survey and route engineering, unexploded ordnance detection, identification and removal, pre-lay grapnel runs and route clearance, boulder clearance and relocation, ROV intervention and dive support, rock bag and concrete mattress installation, and scour protection. The company operates a logistics centre and marine base at Eemshaven in the Netherlands, where it stores submarine cables and accessories, and it provides inspection, maintenance and repair services covering both cables and broader structures. Foundation installation uses the heavy lift vessel Seaway Strashnov and the custom built foundation installation vessel Seaway Alfa Lift, handling monopiles, suction bucket jackets, tripod and pre-piled jackets set with a pile installation frame, driven by impact or vibratory hammer with pile driving noise mitigation measures; a multi-year innovation programme produced a method for installing monopiles on dynamic positioning rather than on anchors. The same heavy lift vessels transport and install offshore substation jackets and topsides, with the DP3 vessel Seaway Strashnov and its 5000t crane suited to that work. Wind turbines are delivered through fully integrated transport and installation services using the jack-up installation vessel Seaway Ventus. Walk-to-work personnel transfer is provided by the installation support vessel Seaway Moxie, designed to let offshore teams reach foundations and platforms in rough seas. A fleet of open deck semi-submersible heavy transportation vessels named Eagle, Falcon, Hawk, Osprey, Swan and Albatross carries wind foundations, offshore modules and other oversized cargoes. Seaway7 is also growing its technical capability in floating offshore wind.