A manufacturer of marine vessels and an international oil and gas services company have agreed to combine their fields of expertise to develop vessels for installing offshore wind farms. Wärtsilä (www.wartsila.com) will provide the new installation vessels with ship design, electrical power generation, propulsion machinery, and high-end automation. Aker Solutions will supply the jacking system. The two companies will also offer a 24/7 global support service for maintenance, repairs, and component supply to the vessels.

The turbine installation vessel can operate in year-round weather conditions at water depths of 4.5 to 50m. Thanks to the optimized deck space around the 1,000-ton offshore gantry crane, three foundations or five complete wind-turbine assemblies of the 5-MW class can be stored on deck
The companies have selected the best technologies for this custom installation vessel. Five Wärtsilä dual-fuel engines will provide main and auxiliary power for the vessel which can operate on liquefied natural gas with low emissions. Heat from the engine will be used to supply drinking water and hot water for crew use. Absorption chiller units will provide air conditioning.
The market for offshore wind farms is rapidly developing as demand for renewable energy sources increase. Because North European offshore wind farms tend to be in shallow waters, 50m or less, so-called jack-up vessels are used for the installation work. At the installation site, the vessel lowers massive legs to the seabed on which the vessel is jacked-up until it is above the waves. A hydraulic grip system is used for this jack-up operation.
Aker Solutions will develop a continuous hydraulic-jacking system for truss legs, a design customized for turbine installation vessels. The jack mechanisms will have redundant systems and a rugged design for operations in harsh environments.
The vessel will fulfill the industry’s requirements for large deck space, sufficient crane capacity, year-round and all-weather operational capability, and cost-efficient operating systems. It is intended for work in the International Maritime Organization’s emission control areas.
“This vessel is already generating significant interest among those involved with the installation and maintenance of offshore wind farms,” says Riku-Pekka Hägg, Vice President, Wärtsilä Ship Design. “There is demand for a high technology and well equipped installation vessel with environmentally sound features. We expect to get the first orders this year.”
WPE
Filed Under: Construction, Offshore wind, Towers