When offshore wind meets national security: lessons from selected European markets

Introduction

Offshore wind is no longer viewed solely through the lens of climate policy or generation capacity. Across Europe, it is increasingly developed as part of a broader strategic infrastructure agenda – one that sits at the intersection of decarbonisation, industrial policy, maritime spatial planning and national security.

As project footprints move further offshore and deployment accelerates, the legal and regulatory framework governing offshore wind becomes more complex. In particular, the interaction between offshore wind farms and defence-related infrastructure – most notably radar systems, surveillance capabilities and military airspace management – is emerging as a material issue for developers, investors and public authorities.

At the centre of this tension lies a well-known technical constraint with significant legal consequences. Wind turbines can interfere with radar systems used for defence, air traffic control and maritime navigation in several ways. They can reduce detection sensitivity, obscure potential targets and generate false echoes. These effects arise because wind turbines, constructed mainly from steel and equipped with large rotating blades, reflect and scatter electromagnetic waves.

In practice, radar interference increasingly shapes where projects can be located, what studies must be carried out, which authorities must be consulted, what mitigation measures are required and at what stage of project development the associated costs must be absorbed.

The national approaches examined in this article show that there is no single model for regulating this interface. Yet a common theme is clear across markets: offshore wind can no longer be regulated as an isolated energy activity. It is increasingly assessed as part of a wider infrastructure and security ecosystem.

This article considers how selected European jurisdictions respond to that challenge. It does not reduce the issue to a purely technical question of radar compatibility. Instead, it examines how radar and defence considerations translate into legal mechanisms, including site selection criteria, perimeter designation, consultation requirements, expert studies, permit conditions, mitigation obligations and ongoing operational duties.

In doing so, it highlights a growing regulatory reality for the offshore wind sector: the success of a project may depend as much on its ability to coexist with defence infrastructure as on its wind resource, seabed conditions or route to market.

Country insights

The Netherlands

Offshore wind farms and radar safeguarding

Offshore wind forms a cornerstone of the Netherlands’ climate and energy strategy. With targets of 21 GW by 2032 and up to 40 GW by 2040, this capacity is essential for the country’s transition to a sustainable energy system.

Legal framework for radar safeguarding

Dutch law requires both onshore and offshore wind projects to avoid interfering with radar systems and to ensure that these systems remain fully operational.

For onshore wind, Article 5.155 of the Decision on the Quality of the Living Environment (Besluit kwaliteit leefomgeving) provides that structures must not interfere with military radar operations. A 75 km safeguarding zone applies around each military radar station.

Within a 15 km zone, maximum tip heights apply based on the following formula: radar antenna height × 0.004363 × distance from the turbine to the radar. Within the 15 km to 75 km zone, fixed maximum heights apply, ranging between 89 and 136 metres depending on the radar station.

Developers may exceed these limits if they demonstrate that the wind turbine does not materially affect radar operations. This requires a technical assessment by the Netherlands Organisation for Applied Scientific Research (TNO) and approval from the Ministry of Defence.

The type of radar also affects project feasibility. Traffic control radars operate within multi-radar networks and are less sensitive to interference. Standalone combat radars are highly sensitive, meaning that interference from wind turbines is more easily established.

For onshore wind and civilian aviation radars, a similar regime applies under Article 5.161a of the Decision on the Quality of the Living Environment. Different zones and maximum heights apply, ranging between 50 and 129 metres. Exceeding these limits requires demonstrating no material impact on radar operations. Construction near airports may also require approval from the Human Environment and Transport Inspectorate (Inspectie Leefomgeving en Transport).

For offshore wind, the applicable regime depends on location. Where wind farms are located within territorial waters and covered by a municipal environmental plan (omgevingsplan), the same rules as for onshore wind apply.

For projects outside municipal areas, either within territorial waters (12 nautical miles) or the exclusive economic zone, radar requirements are set by the Dutch State in a wind farm site decision (kavelbesluit).

A wind farm site decision is a formal decision under the Offshore Wind Energy Act (Wet windenergie op zee). It defines the location, technical requirements, grid connection, environmental safeguards and any radar-related conditions under which the wind farm must be built and operated. Non-compliance may lead to enforcement action, including suspension of construction or operation.

Combined use of military zones and offshore wind farms

Radar safeguarding is evolving. The Dutch government is investing in enhanced radar coverage and new radar stations, including the new system in Herwijnen, to maintain operational reliability as offshore wind capacity grows.

The government is also assessing whether military training areas in the North Sea can be combined with offshore wind farms without compromising operational safety or damaging infrastructure. Current focus includes the EHD-42 area north of the Wadden Islands, a large military exercise zone adjacent to designated wind energy areas.

Conclusions

The Netherlands is progressing rapidly towards its offshore wind targets but this brings complex challenges. Radar safeguarding and defence operations are not peripheral issues. They are prerequisites for national safety and for the secure development of the offshore wind sector.

Developers should expect radar interference assessments to become more stringent as wind capacity expands and military radar networks modernise. For projects near safeguarding zones, early engagement with TNO and the Ministry of Defence is advisable.

Norway

Regulatory framework and area opening mechanism

The Norwegian regulatory framework for offshore wind is based on national petroleum legislation. As such, the government decides which areas may be opened for offshore wind projects.

Currently, two areas have been opened: Sørlige Nordsjø II, where Ventyr SN II AS won the auction for a project area in March 2024, and Utsira Nord, where two project areas for floating windfarms were allocated in Q1 2026. One area was awarded to Utsira Nord Havvind DA, owned by Equinor and Vårgrønn, and another to Harald Hårfagre AS, owned by Deep Wind Offshore Norway AS and EDF Renouvelables International SAS.

When selecting areas, the government assesses technical suitability and the level of conflicting interests. This explicitly includes environmental considerations and industries such as petroleum and fishing. It likely also includes the interests of the Norwegian Armed Forces. As a result, one would assume that if an offshore wind project may interfere with radar or defence infrastructure, the government is unlikely to open the area. However, recent developments show that this may not always be the case.

Impact assessment and treatment of radar interference offshore

Recently, a consultation response from the Norwegian Armed Forces to the proposed impact assessment programmes for the project areas in Utsira Nord was published. They highlight that the planned development of large-scale floating offshore windfarms in the vicinity of military test areas could have significant consequences for the Armed Force’s ability to carry out necessary testing and verification of military equipment, such as sonars, radars and other communications systems. They also point to a local military restricted area, where no cable routes, construction traffic, rigging, temporary anchoring or storage of components is allowed.

The Armed Forces therefore request the following mitigating measures for Utsira Nord:

1. that the developers are required to use wire or synthetic fibre instead of traditional chains for their mooring lines to limit noise;
2. that a comprehensive hydroacoustic impact assessment is carried out;
3. that a technical report detailing how the mooring system will eliminate dynamic structure-borne noise is required; and
4. that the developers must document that the planned cable routes for transmission of electricity to shore avoid the military restricted area in its entirety and that no operations will affect the restricted area.

The impact assessment programme for Ventyr’s proposed project in Sørlige Nordsjø II includes an assessment of potential effects on civilian radar systems and electronic communications. For security reasons, Ventyr is not required to assess impacts on military radar systems. However, the developer must assess how the project may affect the activities of the Armed Forces, including plans for the military’s local training airspace.

Radar interference in practice: distance thresholds and case-by-case assessment

Until recently, radar interference has been a more prevalent topic for onshore wind than for offshore projects.

The Armed Forces consider that no wind farms should be located within 10 km of permanent radar installations. Disturbance is likely acceptable beyond 30 km, but each case requires an individual assessment. This assessment is typically included in the impact assessment.

Onshore wind: permitting structure and relevance for radar assessment

For onshore wind, site selection is not centrally determined. It depends on three main factors:

1. where the developer identifies favourable conditions;
2. whether the developer can secure agreements with landowners; and
3. whether the developer can obtain local and regulatory approvals, including zoning plans and licences for construction and operation.

As part of the licensing process, the developer must submit a proposal for an impact assessment programme to the Norwegian Water Resources and Energy Directorate (NVE), which publishes it for consultation. The proposal defines the scope of the assessment.

Following consultation, the NVE determines the final programme, which the developer must complete. The results form part of the licence application.

Practical examples from licensing practice

Two recent examples illustrate how this process works in practice.

Fortum Nordkraft Vind DA is developing Reinelva wind farm in Finnmark. During consultation, the Armed Forces identified a significant risk of interference with their radar in Honningsvåg, located 20 km from the project site. As the radar is scheduled to be decommissioned in 2029, the proposed mitigation was to postpone the project until that time.

The NVE required the developer to verify this position with the Armed Forces. Given the temporary nature of the impact, the NVE did not consider it a significant constraint on project development. The final impact assessment has at the time of writing not yet been published.

A similar situation arose for Moifjellet wind farm in southwest Norway, developed by Statkraft Vind Utvikling DA. The Armed Forces indicated that the project would likely affect an existing radar. However, this radar is due to be replaced with new technology designed to reduce interference.

The NVE required the developer to assess impacts on defence installations, with a focus on communication, navigation, radar and non-aviation surveillance systems. The final impact assessment has at the time of writing not yet been published.

Decision-making process and licensing outcome for onshore wind projects

Once the licence application is submitted, the NVE conducts a holistic assessment based on the application, the impact assessment, consultation responses and its own expertise.

The outcome is either a licence, potentially subject to conditions to mitigate identified risks, or a rejection.

Poland

Offshore wind as a structural element of Poland’s energy policy

Offshore wind in Poland has moved beyond planning and is now in the execution phase. Phase I projects are under construction, while Phase II projects secured support in the auction held in December 2025. This ensures continuity of the investment pipeline into the 2030s.

Offshore wind is a core pillar of Poland’s energy transition. The Energy Policy of Poland until 2040 originally envisaged approximately 5.9 GW of offshore wind capacity by 2030 and 11 GW by 2040. The National Energy and Climate Plan adopted by the Council of Ministers in June 2026 provides a more current policy reference, projecting approximately 5.9 GW by 2030 and 17.9 GW by 2040.

The sector is also driving a geographical shift in electricity generation towards the Baltic coast. This requires significant investment in transmission infrastructure to connect northern generation hubs with demand centres across the country.

Offshore wind is developing alongside other strategic assets, including the planned nuclear power plant on the Baltic coast. This reinforces the role of northern Poland as a future energy hub.

A multi-layered legal framework

Despite dedicated offshore wind legislation, the regulatory framework is complex. It combines sector-specific rules with broader regimes such as maritime and environmental law. It also includes a distinct layer of national security regulation.

As a result, the permitting process assesses traditional factors such as location and environmental impact alongside issues such as potential effects on defence infrastructure. Offshore wind projects are increasingly treated as elements of critical infrastructure. This justifies the involvement of authorities responsible for defence and internal security.

Offshore location licence and early-stage integration of defence considerations

A key feature of the Polish regime is the offshore location licence (OLL). This is the first major milestone in the project lifecycle and is obtained before environmental or grid approvals.

The OLL does more than allocate space. It defines the conditions under which the project may proceed, including national security requirements.

The Ministry of Defence and the Ministry of Interior and Administration are actively involved. As a result, defence considerations are integrated at an early stage. Phase I licences already include obligations to address the impact on military systems, including radar.

Radar interference as a legally relevant constraint

Radar interference is well understood technically. Rotating turbine blades can disrupt radar signals and affect detection and tracking.

In Poland, this issue is central to the permitting process. Developers must carry out detailed studies on the impact of offshore wind on radiolocation systems, observation systems, military communication networks and air traffic control.

These studies are comprehensive and scenario-based. They define risks and determine mitigation measures. They therefore influence both project design and cost.

Mitigation obligations and their legal implications

Mitigation measures are technically complex and legally significant. In practice, they may include installing radar systems on selected turbines to offset interference and maintain monitoring capabilities.

Two points are key from a legal perspective:

• Developers bear full responsibility for implementing and financing mitigation measures. This directly affects project economics.
• Radar systems may qualify as military or dual-use equipment. Their installation may require separate permits or concessions, adding complexity and timing risk.

Structural risks and system-level considerations

The current framework allocates obligations on a case-by-case basis through the OLL. While this allows flexibility, it raises concerns about system coherence.

There is a risk that multiple projects will implement separate mitigation solutions without coordination. This may prompt future regulatory intervention, including system-level solutions or a redistribution of responsibilities.

Additional complexity arises because projects are located in the exclusive economic zone. While Polish law applies, enforcement and integration with state-controlled defence systems present additional challenges.

Conclusions

The Polish framework shows that large-scale energy projects now operate within broader regulatory environments that extend beyond traditional sectoral boundaries. National security considerations are embedded in the core permitting process.

Developers and investors must adapt. Radar interference and defence issues should be addressed at the earliest stages, as they affect timing, design and cost.

Poland reflects a broader European trend: energy transition objectives are increasingly aligned with national security priorities. In this environment, successful project delivery depends not only on technical and financial capability, but also on the ability to navigate a complex and evolving legal landscape.

Romania

Integrated regulatory framework and early-stage security considerations

The development of offshore wind in Romania, particularly in the Black Sea, is governed by a multi-layered legal framework combining energy regulation, maritime spatial planning, environmental protection and national defence requirements.

Given the presence of radar systems, military operations and other strategic assets along the Romanian coastline, developers are required to demonstrate compatibility with these functions from the earliest stages of project planning.

Offshore Wind Law and project lifecycle regulation

At the core of the framework is Offshore Wind Law No. 121/2024 (the Offshore Wind Law), which establishes the legal regime for the designation and concession of offshore wind perimeters.

The law provides a comprehensive regulatory structure, including:

• allocation of institutional responsibilities;
• rules governing the concession of offshore wind perimeters; and
• conditions applicable throughout the project lifecycle, from exploration and construction to operation and decommissioning.

It also sets out the full permitting architecture, covering all required authorisations, approvals, permits and licences.

The Offshore Wind Law further clarifies the roles of competent authorities and requires coordination with institutions of strategic importance. Grid connection and system security requirements remain within the competence of energy authorities and the transmission system operator.

Maritime spatial planning and compatibility of uses

Romania has transposed the EU Maritime Spatial Planning Directive, establishing a framework for the designation of maritime areas and the management of competing uses in the Black Sea.

Designated uses include:

• energy development;
• navigation corridors;
• environmental protection areas;
• military training zones; and
• areas hosting radar, surveillance and other security infrastructure.

Any conflicts with these designations must be resolved prior to the approval of an offshore wind perimeter.

Environmental impact assessment and radar-related considerations

Offshore wind projects are subject to mandatory environmental impact assessment (EIA) procedures.

The EIA evaluates, among other aspects:

• impacts on maritime and aviation safety;
• navigation systems;
• civil and military radar infrastructure; and
• broader security-related operations, insofar as they relate to environmental or operational risk.

Radar and defence considerations are therefore addressed as formal compatibility and risk factors at an early stage.

Role of defence authorities and expert studies

Under the Offshore Wind Law, the Ministry of National Defence is a mandatory participant in the inter-ministerial procedure for the identification, assessment and approval of offshore wind perimeters.

Prior to any concession auction, an expert study must be carried out to assess compatibility with existing uses, including:

• military operations;
• surveillance systems; and
• constraints linked to national security and public order.

Developers are expected to assess radar impacts, including cumulative effects, and agree proportionate mitigation measures.

Permitting requirements and defence approvals

Concessionaires must obtain approval from the Ministry of National Defence for the construction of new infrastructure and the expansion of existing facilities in the Black Sea.

In parallel, projects are subject to a comprehensive permitting and consultation process under Romanian and EU law, including:

• environmental impact assessment;
• maritime spatial planning compliance;
• water management permits;
• aviation approvals; and
• grid connection approvals.

Cybersecurity and critical infrastructure obligations

Concessionaires holding exploration or operational rights are subject to Law No. 58/2023 on cybersecurity and cyber defence, requiring the implementation of risk management processes covering both operations and supply chains.

In addition, offshore wind operators qualify as operators of essential services under Law No. 362/2018 on the security of network and information systems. They may therefore benefit from support provided by the National Cyber Security Directorate in protecting critical infrastructure.

Ongoing obligations and radar impact studies

Concessionaires must supply national defence authorities with data necessary to prevent and respond to security risks associated with offshore wind activities.

They are also required to conduct radar impact studies in coordination with the relevant Romanian authorities. These studies assess potential interference with:

• military surveillance systems;
• civil aviation; and
• maritime traffic management systems.

Radar interference and defence compatibility are therefore material considerations both at the perimeter designation stage and throughout project development.

Market development and outlook

The Ministry of Energy has published in July, for public consultation, a draft government decision approving the list of offshore wind perimeters that may be conceded in the Romanian sector of the Black Sea. The proposal is based on a specialist identification and delimitation study commissioned by the Ministry and sets out a phased development approach across three phases, having regard to key maritime spatial planning constraints such as navigation, military activities, fishing, biodiversity and oil and gas activities.

Phase 1 (short-term) comprises perimeters 1, 2 and 3, suitable for fixed-foundation projects, with a combined capacity of approximately 3.1 GW, expected to meet Romania’s 3 GW by 2035 target under the 2025-2035 Energy Strategy. Phase 2 (medium-term) comprises perimeters 4 and 5, with a combined capacity of approximately 2.4 GW, overlapping a sensitive military area that would need to be relocated before development. Phase 3 (long-term) consists of development zone 6, with a capacity of approximately 6 GW, expected to require deep-water fixed or floating foundation technologies and likely to be developed only after 2035.

Adoption of the decision is an essential step in implementing the offshore wind regulatory framework and a precondition for launching competitive concession procedures, in line with Romania’s National Recovery and Resilience Plan commitments. The approved list is strategic in nature and does not, by itself, confer development rights. Individual projects remain subject to concession, permitting and environmental impact assessment procedures.

The remainder of the secondary legislation governing offshore wind concessions, including concession terms and conditions, procurement implementation rules and the royalty and tax regime applicable to offshore wind concessions, is expected to be adopted by the end of August 2026.

The Offshore Wind Law allows the Ministry to grant state aid for the construction and operation of offshore wind projects, subject to commissioning within eight years from execution of the concession contract. Support is expected to be structured through a contracts for difference (CfD) mechanism, building on Romania’s existing framework for low-carbon technologies.

Subject to the adoption of secondary legislation and implementation of support schemes, the first offshore wind auction is expected in 2027, with an initial capacity of approximately 3 GW, corresponding to the Phase 1 perimeters.

Subject to the adoption of secondary legislation and implementation of support schemes, the first offshore wind auction is expected in 2027, with an initial capacity of approximately 3 GW.

United Kingdom

Growing tension between offshore wind and radar systems

The interaction between offshore wind farms and aviation and defence radar systems has become increasingly complex in UK waters. Rapid maritime development has reduced the number of suitable sites for new projects.

As a result, developers face growing pressure to build in areas that overlap with the coverage of civil and military radar systems. This creates a clear tension between energy development and national security requirements.

Consenting framework

The applicable consenting regime depends on both jurisdiction and project capacity.

In England, offshore wind projects exceeding 100 MW require a Development Consent Order (DCO) under the Planning Act 2008. The Secretary of State for Energy Security and Net Zero (DESNZ) determines the application. The DCO combines the consents and marine licences required for development. Smaller projects require consent under Section 36 of the Electricity Act 1989, although most projects now exceed this threshold.

In Wales, the Infrastructure (Wales) Act 2024 applies to projects between 50 and 350 MW under the Infrastructure Consent Order (ICO) regime. Projects above 350 MW fall within the DCO regime. Projects below 50 MW require consents under the Electricity Act 1989 and the Marine and Coastal Access Act 2009.

In Scotland, the Planning Act 2008 does not apply. Offshore wind projects require consent from Scottish Ministers under Section 36 of the Electricity Act 1989, together with marine licences under the Marine (Scotland) Act 2010 and or the Marine and Coastal Access Act 2009, depending on location.

The Isle of Man operates a separate regime under the Marine Infrastructure Management Act 2016 (MIMA). It has recently accepted for examination an application for its first offshore wind project.

Across all jurisdictions, impacts on radar and aviation are material planning considerations. Decision-makers must weigh these impacts when determining whether to grant consent. Where impacts are significantly adverse, particularly where they may compromise safety or security, they carry substantial weight and may prevent a project from proceeding.

All offshore wind projects must also be supported by an Environmental Impact Assessment (EIA). The EIA must assess effects on human health and material assets, including aerodromes, defence infrastructure and navigation systems. It must also consider the vulnerability of projects to major accidents and disasters.

Policy context

UK policy recognises the interaction between wind farms and radar systems. However, practical challenges remain.

In England, the Overarching National Policy Statement for Energy (EN-1) addresses this interaction directly. It states:

“All aerodromes, covering civil and military activities, as well as aviation technical sites, meteorological radars and other types of defence interests (both onshore and offshore) can be affected by new energy development. Collaboration and co-existence between aviation, defence and energy industry stakeholders should be strived for to ensure scenarios such that neither is unduly compromised.”

EN-1 also acknowledges that interference may occur and may be acceptable in some cases:

“Energy infrastructure development may interfere with the operation of [Communication, Navigation and Surveillance] systems such as radar. This is a particular problem for wind turbines as they can act as a reflector or diffractor of radio signals upon which Air Traffic Control Services and Air Defence Operations rely…”

In Scotland, the Offshore Wind Policy Statement 2020 contains limited specific guidance. It refers mainly to the UK Offshore Wind Sector Deal and emphasises the need for a long-term and coordinated solution to radar interference. However, it does not provide detailed guidance on implementation.

Welsh and Manx policy currently contain no specific provisions on radar impacts.

Policy in practice – planning requirements

In practice, radar impacts are often a key issue in determining offshore wind applications. The Ministry of Defence (MoD) frequently objects to projects where interference with defence radar systems is expected.

The usual outcome is the inclusion of requirements or conditions within the DCO or consent. These conditions require developers to secure approval of mitigation measures at a later stage, once the final design is confirmed. A similar approach applies to civilian systems, typically through National Air Traffic Services (NATS) and aerodrome operators.

Mitigation conditions usually require approval before key milestones, such as installation of turbine blades or commencement of operations. This timing suggests that developers have sufficient time to prepare mitigation schemes.

However, commercial realities require earlier action. Mitigation schemes can be among the most expensive elements of a project. Developers must therefore define these measures at the funding stage and present them to lenders or include them in subsidy applications.

Although EN-1 encourages radar operators to futureproof infrastructure, this has not yet reduced the financial burden on developers.

The situation is further complicated where projects interact with multiple defence and aviation assets. For example, the Morecambe Offshore Windfarm Generation Assets Order 2025 includes six separate requirements for protecting aviation and defence infrastructure, each requiring distinct mitigation measures.

Government response and emerging solutions

The UK government has recognised the growing cost burden on developers associated with radar mitigation which is arising at ever earlier stages in their projects contrary to the intention of the mitigation conditions. In response, it has committed to fund selected long-term air defence radar solutions under the MoD’s Programme NJORD.

This approach removes funding obligations for developers at four radar sites and supports delivery of the Clean Power 2030 Mission. In March 2026, the government also procured new radar systems designed to coexist with offshore wind. These are expected to unlock up to 10 GW of additional capacity.

However, these measures are limited to specific locations. Uncertainty remains for projects interacting with other MoD assets or future developments.

Outlook

Further action is required to resolve the conflict between offshore wind development and national security infrastructure. Achieving the right balance will depend on coordination between industry, the MoD and government. This reflects a broader debate in the UK on balancing energy security with national defence priorities.

Cross-Jurisdictional observations and key takeaways

Across the jurisdictions reviewed, one point is clear: radar interference and defence considerations are central to offshore wind development. They are no longer peripheral issues. They form a key part of both regulatory and commercial decision-making.

The main differences between markets lie in timing and approach. Some jurisdictions address these issues at the area selection stage, while others manage them during permitting. In all cases, they can materially affect site selection, timelines, costs and project delivery.

For developers and investors, this has clear implications. Defence compatibility may determine whether a project is viable, which technical solutions are required, which authorities must be engaged and what additional costs arise. It must therefore be assessed from the outset alongside seabed rights, grid strategy and environmental constraints.

A second trend is the growing involvement of public authorities beyond traditional regulators. Defence ministries, aviation bodies and cybersecurity institutions are increasingly influential. This adds complexity but reflects a broader shift towards treating offshore wind as strategic infrastructure.

Finally, mitigation approaches vary across Europe. Some markets are moving towards coordinated solutions, while others continue to place responsibility on individual developers. This distinction has clear commercial implications.

In an increasingly constrained offshore environment, successful projects will be those that can navigate not only energy and environmental regulation, but also the expanding interface between offshore wind and national security.