The latest addition to Danish naval architectural consultancy Knud E. Hansen’s Atlas series of wind turbine installation vessels (WTIV) designs, the Atlas A-class, is able to carry four new-generation 14 MW wind turbines and is tailored for cost-effective installation of large-scale wind farms.
It is specifically dimensioned for transporting and assembling wind turbines on top of pre-installed foundations. With growth in the offshore wind sector creating more opportunities for specialized vessels, the foundations, which are heavy but do not require jacking, can be efficiently installed from a heavy-lift vessel. As a result, the Atlas A-class has been entirely optimized for the jacking operation, with a 1600-2500 tons crane and minimal system weight for the jacking equipment.
The A-class design can be highly customized by selecting cranes, thrusters, generators and jacking systems according to the specific requirements of the client, as well as availability from the manufacturers. Knud E. Hansen says this offers important competitive advantages over less flexible, off-the-shelf designs.
The powering of the vessel is provided by eight generators connected to a DC grid and a battery pack, allowing the engines to run at variable speed for fuel efficiency while also utilizing load leveling and peak shaving. The batteries not only provide instant power, avoiding unnecessary spinning reserve power from the generators, but also make it possible to recover approximately 60% of the energy used for jacking, when the jacking units are reversed on the way down. Furthermore, the high-speed electrical rack-and-pinion jacking system is designed for 5,000 load cycles, ensuring that the legs and components will withstand wear throughout the life of the vessel, avoiding costly and resource-heavy replacements along the way.
The main deck of the accommodations block includes an operations center consisting of offices and meeting rooms as well as a hospital, day room, TV room, change room, and workshop. Above this is a large galley with spacious mess as well as ample provision rooms.
The three decks above include a total of 114 cabins for contractors, crew and officers. The top deck consists of a bridge with center and wing consoles and a large helicopter deck. Below the main deck is a gymnasium, cinema, TV room, games room, and sauna as well as a laundry room and store rooms.
- Length Overall (excluding helideck) 155.40 meters
- Breadth molded 57.40 meters
- Depth to Main Deck 12.50 meters
- Draf, moulded @ 14,000 tdw 6.50 meters
- Speed @ 6.20 m draft incl. 10% s.m. 12 knots