The introduction of the maritime autonomous surface ships (MASS) accompanied by alternative fuels to the maritime industry is about to open a new era and lead to a new paradigm shift in terms of safety, security, and environmental protection. However, there are also some concerns on new technology which also can create new types of risks such as non-navigation risks and cybersecurity threats. This paper presents recent trends for developing autonomous vessels with the introduction of the latest projects around the globe. It also investigates the individual and combined impact of the MASS on regulations, technologies, and industries in response to the new paradigm shift in the maritime sector. Additionally, other key issues including safety, security, jobs and training, and legal and ethics are addressed to find a solution for an efficient, reliable, safe, and sustainable shipping in the near future. It is suggested that holistic approaches for developing the technology and regulatory framework are to be implemented, and the communication and cooperation of multiple stakeholders based on mutual understanding are vital for a successful arrival of the MASS in the maritime industry.

The paper aims to investigate the holistic environmental benefits of using a battery system on a roll on/roll off (ro-ro) passenger ship which was originally fitted with a diesel engine engaged in Korean coastal service. The process of this research has multiple layers. First, the operating profiles of the case ship were collected, such as speed, output, operation time and the configuration of the diesel propulsion system. Second, the full battery propulsion system, in place of the diesel system, was modelled and simulated on a power simulation software (PSIM) platform to verify the adequacy of the proposed battery propulsion system. Then, the life cycle assessment method was applied to comprehensively compare the environmental footprint of the diesel-mechanical and fully battery-powered vessels. A focus was placed on the life cycle of the energy sources consumed by the case ship in consideration of the South Korea’s current energy importation and production status. Three life cycle stages were considered in the analysis: ‘production’, ‘transport’ and ‘use’. With the aid of Sphera GaBi Software Version 2019 and its extensive data library, the environmental impacts at the energy production and transport stages were evaluated, while the same impacts at the use stage were determined based on actual laboratory measurements. The environmental performance of the two scenarios in four impact categories was discussed: global warming potential (GWP), acidification potential (AP), eutrophication potential (EP) and photochemical ozone creation potential (POCP). Results of the comparative analysis are presented based on estimates of the overall reduction in the environmental impact potential, thereby demonstrating the overall benefits of using a battery driven propulsion, with a decrease of the GWP by 35.7%, the AP by 77.6%, the EP by 87.8% and the POCP by 77.2%. A series of sensitivity analyses, however, has delivered the important message that the integration of batteries with marine transportation means may not always be the best solution. The types of energy sources used for electricity generation will be a key factor in determining whether the battery technology can ultimately contribute to cleaner shipping or not. By casting doubts on the benefits of battery propulsion, this paper is believed to offer a meaningful insight into developing a proper road map for electrifying ship propulsion toward zero emission of shipping.

This research was focused on a comparative analysis of using LNG as a marine fuel with a conventional marine gas oil (MGO) from an environmental point of view. A case study was performed using a 50K bulk carrier engaged in domestic services in South Korea. Considering the energy exporting market for South Korea, the fuel supply chain was designed with the two largest suppliers: Middle East (LNG-Qatar/MGO-Saudi Arabia) and U.S. The life cycle of each fuel type was categorized into three stages: Well-to-Tank (WtT), Tank-to-Wake (TtW), and Well-to-Wake (WtW). With the process modelling, the environmental impact of each stage was analyzed based on the five environmental impact categorizes: Global Warming Potential (GWP), Acidification Potential (AP), Photochemical Potential (POCP), Eutrophication Potential (EP) and Particulate Matter (PM). Analysis results reveal that emission levels for the LNG cases are significantly lower than the MGO cases in all potential impact categories. Particularly, Case 1 (LNG import to Korea from Qatar) is identified as the best option as producing the lowest emission levels per 1.0 × 10⁷ MJ of fuel consumption: 977 tonnages of CO₂ equivalent (for GWP), 1.76 tonnages of SO2 equivalent (for AP), 1.18 tonnages of N equivalent (for EP), 4.28 tonnages of NMVOC equivalent (for POCP) and 26 kg of PM 2.5 equivalent (for PM). On the other hand, the results also point out that the selection of the fuel supply routes could be an important factor contributing to emission levels since longer distances for freight transportation result in more emissions. It is worth noting that the life cycle assessment can offer us better understanding of holistic emission levels contributed by marine fuels from the cradle to the grave, which are highly believed to remedy the shortcomings of current marine emission indicators.

With increasing interests in using LNG as a marine fuel, safety issues for LNG bunkering have brought about global discussion on establishing a safety exclusion zone around LNG bunkering areas. However, international consensus has yet to be reached in determining an appropriate extent of the zone to ensure safe liquefied natural gas (LNG) bunkering. The purpose of this study is to identify potential risks of LNG bunkering and to present a statistical method for determining the safe exclusion zone around LNG bunkering station with the help of a purpose-built computer program, integrated quantitative risk assessment (IQRA). A probabilistic risk assessment approach was adopted in this study to determine the safety exclusion zone for two case ships: one, a 300,000 DWT very large ore carrier (VLOC) and the other a 32,000 DWT bulk carrier. The results are then compared with those obtained by a deterministic approach and the discrepancies are discussed. It was found from this study that the frequency of bunkering is one of the key factors in determining the extent of safety exclusion zone. Thus, a somewhat surprising result of 36 m radius safety exclusion zone for the 32,000 DWT bulk carrier compared to 6.4 m radius for the 300,000 DWT VLOC was obtained. It was also found that the deterministic approach produced a much more extensive safety exclusion zone for the 300,000 DWT VLOC subjected to infrequent large-scale LNG bunkering operations compared to the probabilistic approach, while it was reasonably consistent with the probabilistic approach for the 32,000 DWT bulk carrier which uses frequent small-scale bunkering.