ABSTRACT
In the maritime market, fossil-derived fuels have been dominated by ‘heavy fuel oil’ (HFO), which is conventionally used in low-speed (main) engines, and more refined fuels such as ‘marine diesel oil’ (MDO) which is used in fast or medium-speed engines. Nonetheless, rising fuel costs and regulatory pressure such as sulfur content restrictions have increased interest in the use of alternative fuels. A variety of such fuels have been reported and can be used in the maritime sector, including ‘straight vegetable oil’ (SVO) as an alternative to HFO in low-speed engines, biodiesel as a replacement for MDO/‘marine gasoil’ (MGO) in low-to-medium-speed engines and ‘bio-liquid natural gas’(bio-LNG) in gas engines using LNG. Potential sources are defined for biomass feedstocks, conversion pathways, and technologies. In particular, the availability, technological development, technical integration, and operational implications are examined with respect to the main parameters, which limit their potential application. It is suggested that a solution needs to be found to address those limitations. Successful implementation of these strategies would allow for a broader use of biofuels in marine applications, significantly reducing ship pollution and enhancing global air quality, as well as protecting the environment.
