Through its Offshore Wind Accelerator programme (OWA ), the Carbon Trust has awarded DONG Energy GBP 6 million (DKK 54 million) to co-fund full scale demonstration of a new offshore wind turbine foundation called the Suction Bucket Jacket.
If the demonstration is successful, it could be implemented in future commercial projects from 2017 – including the UK Round 3 projects.
DONG Energy targets to drive down cost of electricity by 40 per cent for projects sanctioned in 2020. Technical innovation in key areas such as foundations is critical to meet this target. The Suction Bucket Jacket was designed by DONG Energy and based on ideas from the SPT Offshore foundation a finalist in a global competition run by the Carbon Trust to find lower cost foundation solutions.
It combines jacket technology, consisting of welded tubular space frames, with suction buckets for anchoring the foundation firmly to the seabed. The bucket foundation (suction caisson) is a well-known concept from the oil and gas industry, where it has been used for more than 30 years for oil platforms installed in the North Sea.
To minimise the time to market for the Suction Bucket Jacket, a full-scale prototype of the foundation will be demonstrated with a turbine as quickly as possible. This will allow the performance and stability to be verified. DONG Energy will demonstrate a full-scale Suction Bucket Jacket prototype at the offshore wind farm Borkum Riffgrund 1, where the sandy soil conditions are highly suitable for testing of this new concept. The foundation will be installed in 2014.
The prototype foundation will be installed with a state of the art measurement system that will provide essential data for the verification of the Suction Bucket Jacket concept. The collaboration will ensure that OWA participants E.ON, Mainstream Renewable Power, ScottishPower Renewables, Statkraft and Statoil will get full insight into this data, and also have full visibility of the fabrication and installation of the new foundation design. This will allow them to evaluate whether to use it in the UK.
The key benefits of the Suction Bucket Jacket are:
• Significant reduction of the foundation cost • Environmentally friendly installation process – Negligible noise emission during the installation – Shorter installation time, decreasing impact on the marine environment • Usable in a number of soil conditions (e.g. sites with mudstone close to seabed surface).
Press release, January 28, 2014; Image: DONG Energy