The first subsidy-free projects for the development of European offshore wind farms have been awarded, featuring 13-15 MW turbines. To make energy production even more competitive, turbine installation ships must also be cost-effective. The SOUL heavy lift jack-up concept contributes to a significant efficiency gain.
A quick and efficient installation of the next generation turbines was launched in February 2017. The SOUL jack-up design concept aims to install the 10-15 MW wind turbines in the same time frame as used today for installing 6-8 MW units, a significant efficiency gain over any jack-up vessel design currently available in the market. The SOUL series come in various sizes, allowing the transport of 3 up to 6 of the next generation 10-15MW wind turbines. The concept is a joint development of Ulstein and Netherlands’ based SeaOwls.
Scaling-up conventional heavy lift jack-up vessel designs proves challenging due to the disproportional weight increase compared to gain in Variable Deck Load (VDL). This has created uncertainty with turbine manufacturers, wind farm operators and installation contractors on how to install the future generation wind turbines. SeaOwls and Ulstein started to work with the optimal jack-up design, a square platform with the legs spaced out as much as possible.
By rotating the optimum jack-up design 45 degrees, a natural bow shape is provided, with two legs and the crane on vessel centre line. One leg is placed in the bow and aft, and one on either of the ship sides. The cruciform structural lay-out makes the solution more than 10% lighter than conventional designs. This leads to the option of construction larger vessels, take on a larger deck load and keep the steel weight low.
In combination with a high capacity crane, SOUL enables operators to take the next step in developing offshore wind farms. With the main crane around the stern leg, optimal main deck reach and over-the-side lifting capabilities is created. The crane reaches 200 metres up from sea level, and has a capacity of lifting 1,250 tonnes at 65 m outreach.
The global offshore wind market is expected to grow by 16% through 2020. The activity is characterised by the wind farms being established further from shore, in higher water depths, and the project capacity is increased continually. (Source: Norwegian Opportunities in Offshore Wind, 2016).
The joint development of this novel jack-up vessel is the logical next step in Ulstein Group’s strategy to reduce cost in the production of renewable wind energy, and to become a leading company in supporting the offshore wind industry with more efficient assets.