Sofia Offshore Wind Farm : RWE completes installation of major offshore converter platform

RWE, a prominent force in the offshore wind industry, has achieved a groundbreaking milestone with the successful installation of the Offshore Converter Platform (OCP) for its flagship Sofia Offshore Wind Farm. This pivotal infrastructure, which converts high voltage alternating current (AC) into high voltage direct current (DC), marks a significant advancement as RWE’s first deployment of High Voltage Direct Current (HVDC) technology in offshore wind energy. The completion of this installation is a crucial step in ensuring the 1.4 gigawatt (GW) project remains on schedule for full operational status by 2026. Once completed, the Sofia Offshore Wind Farm will have the capacity to generate enough electricity to power approximately 1.2 million typical UK homes.

The OCP, a monumental structure constructed over two and a half years and requiring more than 13 million hours of labor, was meticulously transported from Batam Yard in Indonesia to its destination in the North Sea. Notably, it is the largest offshore wind converter platform ever built globally. This achievement highlights the successful collaboration between RWE, GE Vernova, and Seatrium, underscoring the effectiveness of joint efforts in advancing offshore wind technology.

Advancements and Significance of HVDC Technology

The installation of the OCP represents a significant leap forward in offshore wind energy. HVDC technology is pivotal for long-distance power transmission, as it allows for the efficient transfer of electricity with minimal losses over extensive distances. This technology will play a crucial role in the Sofia Offshore Wind Farm by improving the efficiency of power transmission through the 220-kilometer subsea cable route connecting the wind farm to the shore.

Sven Utermöhlen, CEO of RWE Offshore Wind, emphasized the importance of this milestone, stating, “The successful installation of the OCP, the largest converter platform of its kind in the offshore wind industry, is a proud moment for RWE and everyone involved. This project not only highlights our commitment to leading the way in offshore wind but demonstrates the scale and complexity of what can be achieved when we all work together.”

Installation Process and Engineering Feats

The installation was executed by Heerema, utilizing its Sleipnir heavy lift vessel—a technological marvel capable of handling such massive undertakings. This platform, which stands equivalent to an 11-story building and weighs over 13,000 tonnes, was placed onto the jacket structure, setting a new record for the largest lift in offshore wind history.

The jacket structure, constructed as a welded tubular space frame, was initially installed to provide support for the topside facilities. These include essential components such as supports for conductors and risers. With the topside now securely positioned, it will facilitate the conversion of electricity generated by the wind turbines and its transmission to the onshore connection substation.

Technological and Environmental Impact

The Sofia Offshore Wind Farm, situated on Dogger Bank—195 kilometers off the northeast coast of the UK—is set to become one of the most advanced offshore wind projects globally. The wind farm will deploy 100 Siemens Gamesa 14 megawatt (MW) wind turbines, each equipped with cutting-edge technology. These turbines stand 252 meters tall and feature 108-meter carbon and fiberglass blades, with a rotor diameter of 222 meters, sweeping an area of 39,000 square meters.

In a notable advancement in sustainability, 44 of the project’s 100 turbines will be fitted with recyclable blades. This feature underscores RWE’s commitment to reducing the environmental impact of its wind farms and advancing the sector’s sustainability.

Operations and Future Projects

Operational and maintenance tasks for the Sofia Offshore Wind Farm will be managed from RWE’s newly established offshore wind operations base, the ‘Grimsby Hub.’ This facility will also support RWE’s Triton Knoll Offshore Wind Farm. Additionally, RWE is actively developing two Dogger Bank South projects in the region, which collectively are expected to contribute approximately 3 GW of installed capacity to the grid.

As RWE’s largest offshore wind farm to date, Sofia represents a significant advancement in the UK’s renewable energy landscape. It sets new standards for innovation, sustainability, and collaboration in the offshore wind sector, positioning RWE at the forefront of the global transition to cleaner energy sources.