Ammonia as Marine Fuel

Abstract

The maritime industry faces challenges in adopting new technologies and/or operational practices to comply with increasingly strict international, national, and local regulations aimed at reducing Sulfur Oxides (SOx), Nitrogen Oxides (NOx), Particulate Matter (PM), Carbon and Greenhouse Gas (GHG) emissions from ships. The regulations introduced by the International Maritime Organization (IMO), the European Union, the United States Environmental Protection Agency, the California Air Resources Board, and others are designed to reduce these emissions from ships. Many technologies are being considered to reduce carbon emissions in shipping. The American Bureau of Shipping (ABS) publication Setting the Course to Low Carbon Shipping: Pathways to Sustainable Future, referred to as ‘Outlook II’ in this document, has categorized the available maritime fuel options for decarbonization. Among them, ammonia (NH3 ) was identified as a zero-carbon fuel that can enter the global market relatively quickly and help meet the GHG reduction target for 2050 set by the IMO. Ammonia offers ship owners and operators a zero-carbon tank-to-wake emissions profile, regardless of the source of the fuel. Despite its toxicity and stringent handling requirements, ammonia engines have been developed in the past and marine engines are currently being developed by applying existing dual fuel (DF) engine technologies to ammonia. Designs for ammonia-fueled feeder ships have also been unveiled by consortia that include designers, classification societies and shipyards. Ammonia has greater prescriptive requirements for containment and equipment than most of the other alternative fuels under consideration, is a globally traded commodity and there currently exist many smaller gas carriers that may be suitable as bunkering vessels. However, for ammonia to become a commercially-viable long-term fuel option, comprehensive supply-side infrastructure would need to be built and stringent new safety regulations be developed and implemented. This also applies to all alternative fuels under consideration. Through a series of sustainability whitepaper publications, ABS will focus on individually detailing certain carbon emission reduction technologies. This whitepaper provides information for the consideration of ammonia as a marine fuel option in both the near-term and long-term. It is to be noted that the information provided in this document is generic. For specific guidance on ammonia as marine fuel, contact your local ABS office.