Comparative Evaluation of Hydrogen with Other Conventional and Alternative Marine Fuels

Abstract

In the pursuit of reducing greenhouse gas emissions and meeting sustainable energy demands worldwide, renewable and alternative energy sources are becoming increasingly effective instruments. The transportation sector remains a significant source of emissions, with fossil fuels serving as the primary propulsion fuel in maritime transportation due to the widespread use of internal combustion engines in ships. To mitigate the impact of maritime transportation on climate change, reducing fossil fuel dependency in internal combustion engines can contribute to decarbonization in the maritime sector. In this context, hydrogen, a carbon-free fuel, presents a promising solution. It can be used in internal combustion engines through a dual-fuel approach rather than direct combustion, helping to address the limitations of hydrogen combustion while allowing hydrogen to partially replace conventional fuels. This study examines alternative fuels that could be used as marine fuels alongside hydrogen in internal combustion engines, focusing on their combustion performance characteristics. The paper aims to establish criteria for selecting suitable marine fuel sources. A gap analysis is conducted on the compatibility of hydrogen with alternative fuels in marine engines, considering performance characteristics such as combustion duration, efficiency, in-cylinder pressure and temperature, and emissions. Although diesel and natural gas are not classified as renewable fuels, their compatibility with hydrogen makes them viable candidates. Hydrogen-enriched operations could improve the combustion characteristics of internal combustion engines running on alternative fuels.