Published December 2022
The International Maritime Organization (IMO) has set the goal of reducing greenhouse gas (GHG) emissions from the shipping sector by at least 40% by 2030 and by 50% by 2050. This aggressive reduction will need technologies and resources, which will be a significant evolution from the present two-stroke or four-stroke engines burning high-sulfur fuel oils or very low-sulfur fuel oils. Amongst the low-carbon fuels being considered are liquefied natural gas (LNG), ammonia, hydrogen, methanol, and technologies like fuel cells and battery-powered electric engines. And the questions that need answering are: is it safe, is it available, what will it cost, how difficult is it to change the engine to a new fuel, and does it meet the future GHG requirements?
This report looks at some of the more promising fuels/technologies to answer these questions.
Green fuels for shipping is a fledgling industry and much more will be done in the years to come before costs and operational issues are determined with more clarity. Research and development toward better internal combustion engines (ICEs) using methanol and ammonia as well as fuel cells are ongoing and we can expect rapid change.
The report reviews the progress toward the goal set by the IMO and looks at the three most promising green fuels available for marine shipping currently, namely ICEs, primarily for methanol, ammonia, and fuel cell technology, to power ships. It describes, in detail, the information available to that end and the cost estimates for the different options available to convert ships to these options.