Emerging ship design principles for ammonia-fueled vessels

Project Objective:

Using ammonia as a shipping fuel creates many new considerations for ship design. The design of safe and efficient ammonia-fueled ships is therefore an important step towards a zero-carbon future for the maritime industry.

Key Findings:

Safety considerations: While experience with LNG offers a foundation, ammonia’s toxicity introduces new risks. Essential safety features include double-wall containment, proper venting, automatic shutdown systems, efficient detection and alarm systems, early response practices, and remote monitoring to protect crew and ensure vessel operational safety.

Ammonia fuel technology: Ammonia-fueled vessels are equipped with ammonia fuel tank(s), fuel supply systems, bunker station, and ammonia release mitigation systems. Ship design must incorporate features like vent masts and inert systems to manage and handle ammonia ventilation. To ensure a safe and efficient vessel, it is essential to evaluate factors such as the distance of crew accommodations to vent masts, safeguards against physical hazards, and ease of access for maintenance and emergency response. Incorporating advanced monitoring technologies further enhances these efforts by reducing the need for direct human involvement.

Ship design considerations and optimization: Fuel tank placement must balance safety: distance from crew areas and ventilation systems, transfer lines and bunker stations, ventilation of the TCS, and the cargo carrying capacity loss due to tank integration. The tank location should be optimized while ensuring adequate protection. It should minimize pipeline dimensions and routing.

Read more about the findings of the project here.

Leading Members:

Mærsk McKinney Møller Center for Zero Carbon Shipping

Project Participants:

Mærsk, Seaspan, Mitsubishi Heavy Industries, Tsuneishi, NYK Line & Stolt Tankers

 

Sub-project: Inherently Safer Design of Ammonia Fueled Vessels

Objective: The project aims at building clarity and confidence around technical solutions applicable in mitigating hazards onboard ammonia-fueled ship designs, and pertinent standards and regulations in pursuit of a uniform approach.

Project Milestones: 

• Project launched in April 2024

• Technical solution mapping

• Workshop with class societies and technical experts

• Completion of project and used input for Emerging ship design principles for ammonia-fueled vessels

Key findings:

• Alignment on Methodology: It is crucial to have a standardized approach across the industry to ensure consistency and reliability.

• Barrier Effectiveness and Efficiency: Clarification on the effectiveness and efficiency of barriers, such as water curtains, is paramount.

• Integration of Technology and Operations: It is important to account for the human element early in the design phases when integrating technology and operations accounting.

• Comparison with LNG: The project covered also a comparison with LNG as a fuel, highlighting manageable levels with existing technology, technology availability, and the need for new technology.

Read more about the bow-tie analysis with barriers and key take aways here.

Leading Member:

Mærsk McKinney Møller Center for Zero Carbon Shipping

Project team:

Mærsk, Stolt Tankers, Equinor, NYK

Project stakeholders:

DMA, ABS, EMSA, LR, DNV, SIGGTO, SGMF