Amprion is announcing a tender for the construction of an oyster reef in the German EEZ of the North Sea

Amprion GmbH is one of four transmission system operators in Germany. Our 11,000-kilometer high-voltage network transports electricity in an area stretching from the North Sea to the Alps. We keep the grid stable and secure – and pave the way for a climate-neutral energy system by expanding our grid. As part of the energy transition, Amprion ensures that the electricity from the wind farms in the North Sea is made available to society. To this end, grid connection systems such as DolWin4/delta and BorWin4/delta are being built in the North Sea and connected to the onshore power grid. As Amprion attaches great importance to sustainability, consideration is given to animals, the environment and society during construction and operation.

For DolWin4/delta and BorWin4/delta, whose commissioning is planned for 2028, nature conservation compensation measures must be implemented. For this reason, oyster reefs have to be implemented for the projects by 2029 in order to compensate for the environmental impact. The project area for the so called “oyster measure” is located in the nature conservation area Borkum Reef Ground in the German EEZ of the North Sea and has a total size of approx. 26 hectares. The reefs are to consist of a stone base, which will be laid out in patches of loose stones (20-40 cm in diameter). On every hectare, three patches of rocks, each patch with a size of 50 m², have to be placed to provide the seed oysters with a secure base against silting and drifting. These are then populated with oyster seed (European native oyster, Ostrea edulis) to create fully-fledged oyster reefs. A colonization density of approx. 300 individuals/m² within the patches is the target. The seed oysters must come from an ex-situ stock of Ostrea edulis more specifically an oyster hatchery that is managed in accordance with the recommendations of the Native Oyster Restoration Alliance (NORA). The oysters must be cultivated using the “spat on shell” method. The exact specifications for the oyster reefs are set by the German Federal Agency for Nature Conservation (BfN).

Based on the expertise of the NORA network, Amprion GmbH is looking for a contractor to implement these projects. This includes, among other things like the coordination of subcontractors, the execution planning and the implementation of the reef, including the provision of oyster seed and stones. In order to ensure a correct and sustainable implementation of the oyster measure, experience in the establishment of oyster reefs is desired. Experience in the keeping and breeding of Ostrea edulis and the monitoring of oyster reefs in the sea, including all associated parameters, is also desirable.

If you are interested in taking part in this project, please send us an E-Mail to We will provide you with the tender documents which will be made available from 15 July 2024. You have the chance to submit your offer until 15 September 2024.

However, we are recommending receiving the tender documents as early as possible. If you have any questions regarding the project or the tender feel free to contact us at any time. We are looking forward to working with you.