ULSTEIN U-STERN™
Innovative monopile installation with ULSTEIN U-STERN
The offshore wind industry faces challenges with larger monopile foundations.
Our patent-pending ULSTEIN U-STERN offers a safer, smarter, and more competitive solution for transporting, upending,
and installing large monopiles on DP.
Wave-shielding and fuel-efficient monopile installation
The U-STERN™, developed by Ulstein Design & Solutions B.V., allows for longitudinal storage of monopiles and upending in the ship's centre line. This design enables the ship to face the waves during installation, reducing ship motions and fuel consumption, while providing excellent wave shielding. By combining the U-STERN with transverse and longitudinal skidding systems, offshore lifts for monopiles are eliminated, with the main crane only supporting the upending and lowering of the foundation.
- Reduced motions
- The U-STERN™ enables head-to-sea installation with excellent wave shielding, cutting ship motions during monopile handling.
- Fuel savings
- By letting the vessel face the waves and keep a steadier heading during installation, the design reduces power demand and fuel consumption.
- Faster installations
- Longitudinal storage and centre-line upending streamline the sequence, minimising repositioning and shortening cycle times.
- Safer deck work
- Wave shielding and controlled centre-line upending reduce exposure to vessel motions and crane swings for personnel and equipment.
Installing next-generation foundations safer, smarter and more competitive
The U-STERN looks like a simple recess in the stern.
But it is much more than that,
states Ko Stroo, Product Manager/Lead Naval Architect in Ulstein Design & Solutions BV.
The shape and location of the recess are finely tuned with CFD (Computational Fluid Dynamics) and motion analysis to make it work harmoniously with the crane and mission equipment.
More than two years of R&D have enhanced our understanding of improving the dynamics associated with DP monopile installation. This has resulted in the U-STERN having significant benefits over ‘traditional’ monopile installation on the side of a vessel:
- Increased operability due to a 25 % reduction in motions, excellent wave shielding in the ‘moonbay’ and controlled upending of monopiles;
- 50% power reduction in DP (Dynamic Positioning) operations due to weather vaning;
- Avoiding port (and offshore) related challenges related to transverse monopile transport and upending;
- Safer lifting operations offshore;
The idea of longitudinal monopile installation originates in our vast experience in developing heavy lift pipelay vessels with a centerline firing line,
says Edwin van Leeuwen, Managing Director in Ulstein Design & Solutions BV.
The U-STERN is not a ‘one-trick pony’, as the vessel is also suitable for jacket and other heavy lift installation work. In the past months, we have presented the U-STERN to major contractors and operators, many recognizing this as the most viable solution for installing the next-generation monopile foundations.
Ulstein designs pioneering heavy lift vessel for Penta-Ocean Construction
Penta-Ocean Construction, a prominent Japanese general contractor, has commissioned Ulstein Design & Solutions B.V. to design its new heavy lift vessel for offshore wind foundation installation. The customised ULSTEIN HX118 design will feature a 5,000-ton Huisman main crane and the ULSTEIN U-STERN™, which enables the installation of increasingly larger monopile foundations.
Get in touch
Edwin van Leeuwen
- Description
- Managing Director
- Affiliation
- Ulstein Design & Solutions B.V.
Marian Rodriguez Suarez
- Description
- Sales Manager
- Affiliation
- Ulstein Design & Solutions B.V.
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ULSTEIN U-STERN™
Innovative monopile installation with ULSTEIN U-STERN
The offshore wind industry faces challenges with larger monopile foundations.
Our patent-pending ULSTEIN U-STERN offers a safer, smarter, and more competitive solution for transporting, upending,
and installing large monopiles on DP.
