OffChEm – Chemical Emissions from Offshore Wind Farms

Potential impacts on the marine environment and their evaluation

The ongoing development of offshore wind energy in the North Sea and Baltic Sea has an increasing impact on the marine environment. More than 1,000 offshore wind turbines and at least 20 converter and transformer platforms have already been installed. Every offshore installation represents an disturbance in the marine environment. Chemical emissions from these plants have hardly been investigated to date. In this context, necessary measures for corrosion protection systems and the use of operating materials need to be considered. Scientific findings on the quantities released and their distribution in the respective environmental compartments (water, sediment, biota) are currently scarce. A comprehensive assessment of the effects on the marine environment is therefore only possible to a limited extent by the current state of knowledge.

Focus on corrosion protection

Galvanic anodes (so-called "sacrificial anodes") are used to protect offshore constructions against corrosion, whereby large quantities of metal compounds (in particular compounds of aluminium and zinc) are continuously emitted into the marine environment. In addition to the main components, galvanic anodes also contain other metallic by-products (e.g. indium, lead, cadmium and other heavy metals), which are also released into the marine environment during the consumption. In addition, a wide range of polyurethane/epoxy resin-based coating materials are used for surface corrosion protection in the offshore sector. These coatings may contain organic substances which are released into the marine environment during operation due to weathering of the surfaces and leaching from the coatings. They therefore represent a further potential source of pollution for the North Sea and the Baltic.

Aims of the project

In this project, funded by BSH, the Helmholz Centre in Geesthacht investigates the following aspects in collaboration with the BSH:

  • Identification of potential organic and inorganic (harmful) substances which could have a relevant impact on the marine environment through the corrosion protection of offshore farms.
  • Development of analytical methods and suitable sampling strategies to determine the emissions of the potential substances in the various compartments in the vicinity of offshore farms.
  • Evaluation of the relevance of the identified potential pollutants on the basis of their material emissions from offshore farms and their influence on the local and regional marine environment.