Back to roadmapBack to list

Hull cleaning

Hull cleaning removes biofouling from a vessel’s underwater surfaces.

Alternative fuelsMarine shipping

Introduction

Hull cleaning removes biofouling from a vessel’s underwater surfaces. Biofouling includes biofilms and other microorganisms (microfouling), as well as algae and larger organisms such as barnacles and mussels. It increases hydrodynamic resistance and can spread invasive aquatic species between ports. Cleaning can take place in dry dock or in the water. In-water cleaning requires careful control of removed organisms, coating particles, biocides and other potentially harmful substances, in accordance with applicable local requirements.

Value proposition

  • Reduce fuel use and GHG emissions

  • Limit the transfer of invasive species

A clean hull improves vessel efficiency and can reduce fuel use and emissions. It also supports biosecurity by limiting the transfer of invasive species. For ports, controlled hull-cleaning services can strengthen environmental performance and provide vessels with access to compliant maintenance services while in port. The value of hull cleaning depends on safe and effective cleaning methods that do not cause unnecessary wear or damage to the vessel’s coating. Compatibility with different coating systems, reliable capture and treatment of removed biofouling and contaminants, and clear approval procedures are essential. Standardised requirements and transparent responsibilities can reduce environmental risks, accelerate adoption and provide certainty for shipowners, ports and service providers.

Port applicability

Hull cleaning is most relevant to ports with regular vessel calls, sufficient demand from shipowners and suitable operating conditions. These conditions include adequate water depth and visibility, manageable currents, sufficient working space and compatibility with other activities alongside the vessel. Large seaports, repair ports and ports on busy shipping routes may offer the strongest business case for permanent hull-cleaning services. Ports in sensitive ecosystems or areas with strict biosecurity requirements may require stronger controls, such as waste capture, water-quality monitoring and restrictions on cleaning heavily fouled vessels. The port authority may coordinate local conditions and procedures, while permits, approvals and enforcement remain the responsibility of the competent authorities.

Groups of innovations

  • Inspection and performance monitoring

    Divers, Remotely Operated Vehicles (ROV's), cameras, sensors and vessel-performance data identify fouling before cleaning is planned. Timing: immediate; Pros: supports targeted cleaning; Cons: inspections require access to the ships data, expertise and reliable records.

  • Dry-dock cleaning

    The vessel is removed from the water and cleaned in a controlled facility. Timing: available; Pros: strong waste control and full access; Cons: costly and linked to dock availability.

  • In-water robotic cleaning with capture

    Remote or autonomous systems remove fouling and collect debris and wastewater for treatment. Timing: available to scale-up; Pros: limits downtime and diver exposure, may be cheaper overtime; Cons: capex will be higher than non-robotic cleaning.

  • Diver-operated cleaning with capture

    Divers use compatible tools while removed material is collected and treated. Timing: available; Pros: flexible around niche areas; Cons: safety risks and variable operating conditions.

  • Proactive grooming

    Frequent, gentle cleaning removes early fouling before heavy fouling develops. Timing: short term; Pros: protects efficiency; Cons: must match the coating and ship profile.

  • Waste treatment and reporting

    Captured material is filtered, contained, tested where required and sent to an approved waste route. Timing: immediate; Pros: reduces environmental release; Cons: adds equipment, documentation and disposal costs.

Impact

Impact level per aspect
ImpactLevelRemark
Marine biodiversityLarge impact
Controlled cleaning lowers the risk of releasing invasive species.
Port efficiencyMedium impact
In-water services can reduce vessel downtime.
SafetyMedium impact
Robots reduce diver exposure, but operations still require controls.
GHG emissionsMedium impact
A cleaner hull reduces hydrodynamic resistance and propulsion demand.
Digital port ecosystemVery large impact
Inspection and cleaning records support data-based maintenance.

Port characteristics

Ports that may benefit most from facilitating hull cleaning are ports with frequent vessel calls, repair activities and demand for in-water maintenance. Ports in sensitive ecosystems or regions with strict biosecurity requirements may have a greater need for controlled cleaning services, provided that appropriate environmental safeguards are in place. Large seaports may be able to accommodate equipment and waste treatment, while smaller ports may use mobile or provider-owned systems and existing approved waste-treatment facilities. Ports with sheltered berths, safe operating space, manageable currents and other suitable environmental conditions, and clear approval procedures are better prepared. The strongest candidates are ports where authorities, shipowners, cleaning providers and coating manufacturers can agree on safe operating conditions.

Barriers and enablers

Enablers

  • DirectionalityEnabler

    Biosecurity and decarbonisation goals increase demand for effective hull management.

  • TechnologyEnabler

    Robotic cleaning, inspection and capture systems are available and continue to improve.

  • Standards & regulationEnabler

    IMO guidance and ISO 6319:2026 provide a stronger basis for consistent operations.

  • EconomicEnabler

    Services require equipment and treatment capacity, but reduced vessel downtime can support the business case.

  • Stakeholder interactionEnabler

    Approval requires coordination between ports, regulators, ships, cleaners and coating suppliers.

Barriers

  • KnowledgeBarrier

    Ports need expertise on biofouling risk, coatings, capture performance and waste handling.

  • InfrastructureBarrier

    Suitable berths, utilities and routes for captured waste may be limited.

How to implement?

  1. Step 1

    Define objectives, responsbilities and applicable permits

  2. Step 2

    Map demand, environmental risks, sites and waste routes

  3. Step 3

    Creates request, approval, reporting and emergency procedures

  4. Step 4

    Test an approved cleaning method at a suitable berth

  5. Step 5

    Expand providers, sites and treatment capacity if demand is proven

  6. Step 6

    Audit performance and update conditions as standards develop

Timeline

The arrow below represents the expected development of the TRL of hull cleaning.
* Technical Readiness Level

What should a port do in the next 3 years?

A port should first assess vessel demand and local biosecurity risks. It should identify suitable cleaning locations together with the local terminals and clarify permits with environmental and maritime authorities. Approval rules should cover pre-cleaning inspection, coating compatibility, capture, wastewater treatment and reporting. The port can then run a controlled pilot with an approved provider. Results should be used to decide whether permanent or shared regional capacity is justified.

Investment overview

CAPEX: Investments may include cleaning robots, pumps, filtration, storage tanks, monitoring equipment and berth connections. A port may also need a treatment area or an approved route to existing waste facilities. Mobile or provider-owned systems can reduce direct port investment. OPEX: Costs include staff, inspections, permits, equipment maintenance, filters, sampling, waste transport and treatment. Further costs may arise from audits, training and environmental monitoring. Revenues can come from service fees or concessions.

Stakeholder overview

Below is an overview of the required involved stakeholders. Port authorities set local conditions and coordinate approvals. Shipowners decide when cleaning is needed and provide hull, coating and biofouling information. Cleaning providers operate and document the service. Coating manufacturers confirm tool compatibility. Environmental and maritime authorities oversee permits and compliance. Waste companies treat captured material, while class societies, laboratories and technology providers may support verification and monitoring.
Blue stakeholders are essential, white stakeholders are enabling

Knowledge base