The maritime industry, a vital cog in global trade, is under increasing pressure to reduce its carbon footprint. Stringent regulations, growing environmental concerns, and the need for sustainable shipping have driven the industry to seek innovative solutions. Retrofitting existing vessels with advanced technologies is one such approach.

Key Technologies for Decarbonisation

To comply with these regulations and reduce emissions, several technologies can be retrofitted to existing vessels:

1. Air Lubrication Systems (ALS)

• How it works: Air is injected into the water surrounding the hull, reducing frictional resistance.
• Benefits: Reduced fuel consumption, reduced emissions, improved ship performance.
• Challenges: Installation complexity, potential impact on hull structure, and operational requirements.

2. Propulsion Improvement Devices (PIDs)

• How it works: Optimises the flow of water around the propeller, reducing losses and improving efficiency.
• Benefits: Enhanced propulsive efficiency, reduced fuel consumption, and reduced emissions.
• Challenges: Compatibility with existing propulsion systems, potential impact on ship manoeuvrability, and installation complexity.

3. Wind-Assisted Propulsion Systems

• How it works: Utilises wind energy to supplement propulsion power.
• Benefits: Reduced fuel consumption, reduced emissions, and improved ship performance.
• Challenges: Vessel suitability, installation complexity, and operational limitations, especially in calm weather conditions.

4. Alternative Fuel Retrofits

• How it works: Converts vessels to use alternative fuels like LNG or methanol.
• Benefits: Reduced emissions, improved air quality, and potential for future-proofing vessels.
• Challenges: Significant investment costs, infrastructure challenges, and safety risks associated with handling alternative fuels.

5. Hull Modifications and Optimization

• How it works: Modifying the hull shape to improve hydrodynamic performance.
• Benefits: Reduced fuel consumption and reduced emissions.
• Challenges: Complex engineering and construction processes, potential impact on ship stability, and dry-docking requirements.

6. On-board Carbon Capture Systems (OCCS)

• How it works: Captures and stores carbon dioxide emissions from the ship’s exhaust gases.
• Benefits: Reduced greenhouse gas emissions.
• Challenges: High initial investment costs, energy consumption, and operational complexity.

A Deeper Dive into ALS and PIDs Air Lubrication Systems (ALS)

• Passive ALS: This innovative approach utilises the ship’s forward momentum to draw in air and water, creating an aerated mixture that is injected into the boundary layer. This eliminates the need for compressors, reducing complexity and maintenance requirements.
• Benefits of Passive ALS:
  • Reduced fuel consumption
  • Reduced emissions
  • Improved ship performance
  • Lower maintenance costs
  • Rapid installation

Propulsion Improvement Devices (PIDs)

• Becker’s Systems Mewis Ducts: These devices optimise the flow of water around the propeller by reducing wake losses, hub vortex losses, and rotational losses.
• Benefits of PIDs:
  • Enhanced propulsive efficiency
  • Reduced fuel consumption
  • Reduced emissions
  • Improved ship manoeuvrability

The Synergistic Effect of ALS and PIDs

When combined, ALS and PIDs can offer significant benefits:

• Enhanced Fuel Efficiency: By reducing both frictional and propulsive losses, these technologies can lead to substantial fuel savings.
• Reduced Emissions: Lower fuel consumption directly translates to reduced greenhouse gas emissions, contributing to a cleaner environment.
• Improved Ship Performance: Optimised hull and propeller performance can enhance a ship’s speed, manoeuvrability, and overall efficiency.

The Role of Engineering and Project Management

Successful retrofit projects require careful planning, execution, and oversight. A skilled engineering team can:

• Conduct Feasibility Studies: Assess the technical and economic viability of different solutions.
• Detailed Design Engineering: Conduct detailed design engineering including the basic design, detailed design and update other associated plans.
• Manage Procurement and Construction: Oversee the procurement of equipment and materials, as well as the construction and installation process.
• Ensure Regulatory Compliance: Ensure that all retrofit activities comply with relevant regulations and standards.
• Monitor and Optimize Performance: Monitor the performance of retrofitted vessels and adjust as needed to optimise efficiency and reduce emissions.

By working closely with ship owners, operators, and other stakeholders, engineering firms can help deliver successful retrofit projects that contribute to a more sustainable maritime industry.

The future of shipping lies in embracing innovative technologies and sustainable practices. By investing in retrofit solutions like ALS and PIDs, the maritime industry can significantly reduce its environmental impact and ensure a greener future.