HOFOR, Copenhagen’s power supply company, has awarded a contract to Per Aarsleff A/S (Aarsleff) to supply foundations for the Aflandshage offshore wind farm in the Øresund Strait. In addition to the foundations, the contract includes the implementation of Nature-Inclusive Design. This involves the construction of artificial reefs at Aflandshage. The reefs will thus provide a habitat for marine wildlife such as cod, crabs, and other small marine creatures. Furthermore, the artificial reefs will consist of large rocks placed around the 26 concrete gravity-based foundations. Thus, it will create crevices to enhance conditions for fish and other marine animals. This is particularly true for cod, whose population has declined in Danish waters.
The foundations for the Aflandshage wind farm will range in height from 17 to 25 meters and weigh up to 4,000 tonnes. The contract also emphasises minimising the project’s carbon footprint by utilising a material with lower emissions. Aarsleff will use CEM III cement for the concrete, incorporating blast furnace slag, a by-product of iron and steel production. This will help reduce the reliance on regular Portland cement, which has a higher carbon content.
Design for Aflandshage Offshore Wind Farm’s Foundations
The design and planning phase for the foundations will commence immediately, with concrete fabrication, excavation, and rock pad deployment scheduled to begin in 2024. The installation of the first foundations is anticipated in the first half of 2025, with the project expected to be completed by autumn 2025. Ongoing monitoring of the foundation conditions will be conducted throughout the wind farm’s lifespan.
Earlier this year, HOFOR contracted with Siemens Gamesa to supply 26 SG 11.0-200 DD wind turbines for the Aflandshage project. Cadeler will carry out the installation of the turbines. In November 2022, the Danish Energy Agency (DEA) granted an establishment permit for the Aflandshage offshore wind farm, paving the way for its development.