Overview
EN ISO 24656:2022 - Cathodic protection of offshore wind structures (ISO 24656:2022) defines requirements and guidance for the design, implementation, assessment and monitoring of cathodic protection (CP) applied to offshore wind farm structures and appurtenances in contact with seawater or the seabed. Applicable to both external and internal CP, it covers new steel structures, retrofit solutions, residual-life assessment of existing systems, inspection and performance monitoring, and specific guidance for reinforced concrete components.
Key topics and requirements
- Scope and applicability: CP for structures and appurtenances exposed to seawater/seabed environments.
- Competence: requirements for qualified personnel and competence needed to design and maintain CP systems.
- Design fundamentals: objectives, design life, surface area calculations, structure subdivision and material considerations.
- Environmental factors: seawater flow, electrolyte resistivity, temperature and calcareous deposits that influence CP performance.
- Protection criteria: temporary protection, steel structure criteria, and reinforced concrete CP guidance.
- Current demand calculations: methods for estimating protection current for external and internal surfaces.
- Systems and components:
- Galvanic anode systems - alloy selection, current availability, distribution and installation guidance.
- Impressed current systems - DC power sources, anodes, reference electrodes, resilience and installation considerations.
- Hybrid systems and temporary power options.
- Electrical continuity: bonding, current drains and interactions between components and nearby structures (e.g., cables).
- Cables and interfaces: CP DC cable requirements and considerations for inter-array/export AC cable interactions.
- Commissioning, inspection & monitoring: commissioning tests, detailed external/internal surveys, permanent monitoring systems and ongoing CP surveying practices.
Practical applications
EN ISO 24656:2022 provides actionable guidance for preventing corrosion-related failures and extending asset life in offshore wind projects. Practical uses include:
- Designing CP for new turbine foundations, jackets, monopiles and internal ballast tanks.
- Assessing remaining life and planning retrofit CP for ageing assets.
- Selecting galvanic anodes or impressed-current systems to meet project longevity targets.
- Establishing inspection, commissioning and continuous monitoring programs for O&M.
Who should use this standard
- Corrosion and CP engineers
- Offshore wind designers and structural engineers
- Asset owners/operators and O&M teams
- Contractors and suppliers of CP systems (anodes, rectifiers, sensors)
- Inspection bodies and certification organizations
Related information
This EN adoption implements ISO 24656:2022 and was prepared by ISO/TC 156 and CEN/TC 219. Relevant classification codes include ICS 47.020.99 and 77.060 (corrosion, shipbuilding/marine structures). Use this standard alongside national regulations and other marine engineering and corrosion standards when specifying CP for offshore wind assets.
