Wärtsilä and Aker Solutions have agreed to combine their fields of expertise to develop a new and environmentally sound concept for offshore wind farm installation vessels. According to the contract, which was signed earlier this year, Wärtsilä will provide the new installation vessels with the ship design, electrical power generation, propulsion machinery and high-end automation, whilst Aker Solutions will supply the jacking system. Wärtsilä, together with Aker Solutions, will also offer a 24/7 global support service for maintenance, repairs, and component supply to the vessels.

The two companies have selected the best technologies for this custom designed installation vessel, which enables a highly efficient way of setting up offshore wind power generation. The three Wärtsilä 6L34DF and two Wärtsilä 9L20DF dual-fuel engines, that will provide main and auxiliary power for the vessel, can operate on liquefied natural gas (LNG) with low emissions. Similarly, heat from the engine cooling system will be utilized to generate drinking water, and to supply hot water for use by the crew. The accommodation heating on board will also use the same heat source, while absorption chiller units will provide air conditioning during summer months.

Aker Solutions has applied its indepth knowledge of the offshore drilling market to develop a continuous hydraulic jacking system for truss legs, which has been customized for high performance turbine installation vessels. This jack system has great benefits in regard to redundancy, and has a robust design for operations in harsh environments.

The new vessel concept will be marketed as a complete package. It 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.

The market for offshore wind farms is rapidly developing as demand for renewable energy sources increases. Since Northern European offshore wind farms tend to be in shallow waters of 50m or less in depth, 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.