2. Advantages and Disadvantages of Ammonia Versus Other Green Ship Fuels
3. Ammonia in Various Technologies
3.1. Internal Combustion Engines
- Poor ignition
- Slow flame propagation speed compared to other fuels.
- High toxicity and corrosiveness, thus the requirement for sustainable safety and storage solutions.
- High NOx emissions, unless these are controlled either by after-treatment such as Selective Catalytic Reduction or by optimizing the combustion process.
- High costs in production by considering the supply chain and life-cycle considerations, especially if ammonia is produced renewably.
- Lack of regulations if ammonia is to be used as a marine fuel.
3.2. Fuel Cells
4. Blue Versus Green Ammonia
5. Estimated Percentage of Ammonia as Maritime Fuel in 2030 and 2050
6. Adoption of Ammonia for Different Shipping/Vessel Segments and Different Geographical Regions
7. Economic Performance of Ammonia Compared to Other Shipping Fuels, and Projected Development by 2030 and 2050
8. Regulations Impacting Ammonia’s Use as a Shipping Fuel
- High production costs, predominantly due to the high capital costs associated with ammonia’s supply chain.
- Issues with availability, specifically in terms of the number of geographical locations available for ammonia bunkering.
- Ramping up of ammonia production, since currently ammonia is used for the fertiliser industry.
- Development of ammonia-specific rules for its use as a maritime fuel. These rules will need to address issues of toxicity, safety, and storage.
- The large energy penalty associated with the overall reduction in the efficiencies of power plants (and associated operational costs);
- A lack of technical expertise due to the unavailability of plants with CCS;
- An incorrect public perception regarding the maturity of renewable energy sources compared to the available CCS technologies.
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
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|Fuel||Energy Density LHV (MJ/kg)||Volumetric Energy Density (GJ/m3)||Renewable Synthetic Production Cost (MJ/MJ)||Storage Pressure (Bar)||Liquefied Storage Temperature (°C)|
|Liquid ammonia||18.6||12.7||1.8||1 or 10||−34 or 20|
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