DDHI Composite Bucket Foundation Test Project

Location

The DDHI Composite Bucket Foundation Test Project is located offshore in China, with specific coordinates at Latitude: 31° 41' 24" and Longitude: 121° 50' 59.9" using the WGS84 geodetic system.

Foundation Type

The project utilizes Composite Bucket Foundations (CBFs), which are innovative foundations designed for offshore wind turbines. These foundations are characterized by their composite structure, combining different materials to enhance stability and reduce construction time and costs.

Design and Engineering

• The CBFs are prefabricated on land, allowing for better control over construction quality and a simplified offshore construction process. This method reduces the need for large-scale offshore installation equipment and minimizes construction noise and waste.
• The foundation includes an air-cushion structure that enhances stability during transportation and installation. The stability of the CBF during towing and installation is ensured by maintaining small roll and pitch angles, typically less than 1°.

Technical Specifications

• Molded Length: 103 meters
• Molded Breadth: 51 meters
• Molded Depth: 9 meters
• Design Draught: 6 meters
• Bucket Diameter: 30 meters
• Bucket Height: 12 meters
• Transition Height: 20 meters
• Tower Height: 78.5 meters
• Tonnage: Approximately -16,900 tons
• Total Mass: Approximately -2,700 tons.

Installation and Transportation

• The CBFs are transported using an integrated transportation-installation technique, which reduces the need for large-scale offshore equipment. This method involves lifting the wind tower with the installation ship, ensuring stability with acceleration values less than 0.01 m/s² and roll and pitch angles less than 0.02° during hoisting.

Environmental and Regulatory Aspects

• The project would have undergone environmental impact assessments and other regulatory approvals similar to those required for offshore wind farms in general. This includes assessments of the physical, biological, and human environment during construction, operation, and decommissioning.

Developers and Stakeholders

• While the specific developers for the DDHI Composite Bucket Foundation Test Project are not detailed in the sources, it is likely managed by companies specializing in offshore wind energy, possibly in collaboration with local and international partners. Major developers in the offshore wind sector include companies like EDF Renewables, Equinor, Ørsted, and others.

Purpose and Significance

• The test project aims to validate the performance and feasibility of Composite Bucket Foundations for offshore wind turbines. It focuses on the floating behavior, stability, and installation techniques of these foundations, which can significantly reduce costs and environmental impact compared to traditional methods.