Singapore-based offshore engineering group Seatrium and Norwegian contractor Aibel have both filed arbitration proceedings over disputes related to their consortium agreement for the DolWin 5 offshore converter platform in the German sector of the North Sea.
DolWin 5 is an offshore HVDC converter platform that transforms electricity generated by North Sea wind farms into high-voltage direct current for efficient transmission to the German onshore power grid. See below for details.
The arbitration requests have been submitted to the Arbitration Institute of the Stockholm Chamber of Commerce and concern disagreements over responsibilities, costs and revenue allocation under the consortium agreement signed in May 2019.
According to Seatrium, the platform was constructed in Singapore and sailed to Aibel’s facility in Haugesund, Norway, in October 2023 for further works. The platform is currently located in Germany’s North Sea waters, and both companies stated that work on the project continues despite the dispute, with delivery targeted for 2026.
Seatrium said the arbitration arises from differences between the parties under the consortium agreement, including disputes over direct scopes of work and joint responsibilities. The company stated that it is contesting the validity of Aibel’s claims and is seeking clarification of the parties’ obligations and liabilities under the agreement.
Aibel confirmed that it has submitted claims related to additional work and costs incurred to complete the project in line with customer requirements, and said that Seatrium has filed counterclaims. Aibel added that the matter has moved to arbitration after reaching a deadlock at the consortium level and described the process as a standard contractual mechanism for dispute resolution.
The two companies have asserted claims against each other for significant sums. Seatrium has made claims of approximately €180 million relating to differences in revenue and cost distribution, while Aibel has filed claims of around €113 million. Aibel has additionally claimed about €17 million in relation to matters it considers part of the joint scope of work.
Seatrium said it is currently unable to determine the financial impact of the arbitration, noting that any outcome will depend on the tribunal’s findings.
How this works
Wind turbines generate electricity offshore
The wind turbines produce alternating current (AC) electricity.AC power is collected within the wind farm
Subsea cables gather the electricity from many turbines and bring it to the offshore platform.DolWin 5 converts AC → DC
The platform converts the electricity from high-voltage AC (HVAC) to high-voltage DC (HVDC).
This step is crucial because DC power can be transmitted over very long distances with much lower losses.Electricity is sent to shore via HVDC cables
From DolWin 5, the power flows through long subsea HVDC cables to an onshore converter station in Germany.Onshore station converts DC → AC again
Once on land, the power is converted back to AC and fed into the national grid.
900 megawatts is enough electricity to power roughly 1 million European households
HVDC is essential because North Sea wind farms are far offshore
Without platforms like DolWin 5, large-scale offshore wind simply wouldn’t work efficiently
