Understand and minimise the environmental impacts of offshore wind energy

The EU’s Offshore Strategy^[1] underlines that the deployment of offshore wind should be based on maritime spatial planning, assessing the economic, social, and environmental sustainability of the installations in a life-cycle perspective, while ensuring co-existence with other activities such as commercial and recreational uses of the sea and fishing. At the same time, it calls for research on the cumulative impacts of offshore energy generation on the environment, which was also underlined in the Communication on Delivering on the EU offshore renewable energy ambitions (2023)^[2].

Our knowledge on such impacts, positive and negative, is more advanced now than when the Offshore Strategy was adopted^[3]. However, there are still significant data and knowledge gaps. Most fieldwork studies have been carried out at very localised sites and often focused on specific species. These ad-hoc studies lead to conclusions that can hardly be generalised. A sound monitoring, measuring multiple pressures and impacts on ecosystems and their services, at wider scale and in interaction with other sea activities, is still largely missing. There is also a need to further develop models and other instruments for environmental risk assessment, identification of mitigation measures and recommendations for restoration measures, considering impacts during construction, operation and maintenance, repowering and decommissioning.

Improving instruments, data, and knowledge on the cumulative environmental impacts of offshore energy, as well as a sound monitoring, is key to ensure that its expected fast and large-scale deployment will be sustainable. It will also better equip the EU to contribute to mitigate such impacts and promote sustainable deployment of offshore wind at regional (e.g., through OSPAR^[4] in the Northeast Atlantic) or subregional (e.g., through the Greater North Sea basin Initiative) level.

Project results are expected to contribute to all of the following expected outcomes:

• The scientific community, public authorities, project designers, permitting authorities, civil society organisations and citizens have better tools (including Maritime Spatial Planning tools), reliable data and knowledge to monitor, assess and minimise the cumulative environmental, including on biodiversity, and socio-ecological impacts of large-scale bottom-fixed and floating offshore wind energy generation, including at sea-basin level and when combined with other planned or existing human activities;
• The monitoring of cumulative environmental impacts, including on biodiversity, of offshore wind installations is improved, with better tools and open data, in a coherent scheme with pre-existing monitoring programs of the marine environment at large scale;
• Ambitious national and regional offshore wind deployment targets are achieved with positive or minimum negative impacts on the marine and coastal environment;
• Deploy offshore wind energy with minimal impact on marine and coastal ecosystems, and, if possible, with net-positive ones.

Proposals are expected to address at least five of the following aspects:

• Provide better knowledge and understanding of the cumulative environmental impacts of the offshore wind energy deployment according to the EU targets, when added to the current and planned human activities carried out in the same areas;
• Expand existing studies, field monitoring, and analysis from local to larger areas, and from site- or species-specific impacts to more general ones. Further develop and deploy field monitoring activities, measuring multiple pressures and impacts on marine and coastal ecosystems and their services, as well as pollution, from installation to decommissioning and possible repowering, including operational phase and maintenance activities;
• Test and demonstrate field monitoring and modelling technologies that allow to go beyond state-of-knowledge, regarding life-cycle environmental impacts of offshore wind energy deployments;
• Improve instruments and models for Maritime Spatial Planning, and environmental assessments at plan and project level that are in alignment with public authorities’ needs;
• Improve modelling capacity and environmental impact assessments of future offshore wind deployment;
• Support the identification of areas where wind energy deployment is particularly suitable without significant environmental impact and areas where on the contrary, it should be avoided;
• Identify strategies, test, and demonstrate technologies that avoid, minimise, mitigate and compensate the environmental impact of bottom-fixed and floating offshore wind energy systems, propose mitigation and restoration measures and if feasible, provide net-positive environmental impacts. The activities carried out under this point are expected to achieve TRL 5 by the end of the project.

Particular attention must be dedicated to ensuring that the data produced in the context of this topic is FAIR (Findable, Accessible, Interoperable and Re-usable) and to leveraging existing community practices for data sharing especially those in the relevant European common data spaces and in the European Research infrastructures.

Complementarities with other ongoing and upcoming Horizon Europe projects are expected to be ensured as well as with the European Digital Twin of Ocean (European DTO) and its core infrastructure, for instance the projects funded under topics:

• HORIZON-CL6-2025-02-CLIMATE-02: The ocean-climate-biodiversity-people nexus: uncovering safe operating space for safeguarding the integrity and health of the global ocean;
• HORIZON-MISS-2025-03-OCEAN-08: EU Digital Twin Ocean: Contribution to the EU DTO core infrastructure through applications for sustainable ocean management;
• HORIZON-MISS-2023-OCEAN-01-06: Innovative nature-inclusive concepts to reconcile offshore renewables with ocean protection;
• HORIZON-MISS-2023-OCEAN-01-08: Integration of socio-ecological models into the Digital Twin Ocean;
• HORIZON-CL5-2024-D3-02-08 Minimisation of environmental, and optimisation of socio-economic impacts in the deployment, operation and decommissioning of offshore wind farms.

In addition to considering the most evident environmental impacts of offshore wind energy systems (displacement, collision risk, exposure to aerial and underwater noise, habitat loss and degradation, pollution, etc.), funded projects must include an analysis of possible new impacts, that may become particularly relevant when a high number of wind energy systems is deployed, for instance in relation to the decommissioning and removal of end-of-life offshore wind energy systems, the presence of dynamic cables suspended in the water column, the impact of submarine geohazards on the dynamic cables or the production of microplastics.

Environmental monitoring data must be open source and be shared with the European Marine Observation and Data Network (EMODnet) and the International Energy Agency Wind Energy Systems Technology Collaboration Programme’s (IEA Wind TCP) Task on the environmental effects of wind energy.

[1] COM(2020) 741 final

[2] COM (2023) 668 final - EUR-Lex - 52023DC0668 - EN - EUR-Lex (europa.eu)

[3] See for instance the ETC/ICM Report 2/2022: Mapping potential environmental impacts of offshore renewable energy, at: https://www.eionet.europa.eu/etcs/etc-icm/products/etc-icm-reports/etc-icm-report-2-2022-mapping-potential-environmental-impacts-of-offshore-renewable-energy

[4] https://www.ospar.org/