Search Results (51)

Greenhouse gas (GHG) emissions from maritime transport account for nearly 3% of global totals, making the decarbonisation of this sector a critical priority. In response, the International Maritime Organization (IMO) adopted the GHG Strategy, targeting the full decarbonisation of international shipping by 2050, with interim milestones in 2030 and 2040. This study evaluates the greenhouse gas fuel intensity of three representative vessel types, an oil tanker, a container ship, and a bulk carrier, using one-year operational fuel consumption data in line with the Regulations of the IMO Net-Zero Framework. Both conventional fuels, including conventional marine fuels, and alternative options, encompassing liquefied natural gas (LNG), e-hydrogen, e-ammonia, e-methanol, and biodiesel, are assessed for compliance during 2028–2035. The findings reveal that conventional fuels are unable to meet future targets, resulting in significant compliance deficits and balancing costs of remedial units. LNG provides short-term benefits but is limited by methane slip. In contrast, e-hydrogen and e-ammonia enable long-term compliance and generate surplus units. E-methanol shows a partial potential, while biodiesel delivers only modest improvements. The results underscore the need for a transition toward near-zero-well-to-wake-emission fuels. This study contributes by combining life cycle assessments with regulatory compliance analysis, offering insights for policymakers and industry stakeholders. Full article

Maritime transport accounts for approximately 80–90% of global trade and nearly 3% of global greenhouse gas (GHG) emissions. In response, the International Maritime Organization (IMO) adopted an ambitious strategy for net-zero emissions by 2050, critically mandating a Well-to-Wake (WtW) life-cycle assessment for fuels. This framework invalidates fuels produced with high carbon intensity, regardless of their emissions at the point of use, thereby compelling the industry to focus on truly clean and sustainable alternatives. This push positions green hydrogen and ammonia as leading solutions, though they present a distinct trade-off. Hydrogen is an ideal fuel with zero-carbon emission in fuel cells but faces significant storage challenges due to its extremely low volumetric energy density and cryogenic requirements. In contrast, ammonia offers superior energy density and easier handling but contends with issues of toxicity and potentially harmful emissions like nitrous oxide. This paper provides a comprehensive review of this complex landscape, analyzing the production, utilization, and associated techno-economic and geopolitical challenges of using hydrogen and ammonia as future marine fuels, with environmental aspects briefly considered. Full article

With the IMO’s 2050 decarbonization target, hydrogen is a key zero-carbon fuel for shipping, but the lack of systematic risk assessment methods for hydrogen-powered marine propulsion systems (under harsh marine conditions) hinders its large-scale application. To address this gap, this study proposes an integrated risk evaluation framework by fusing Failure Mode, Effects, and Criticality Analysis (FMECA) with the Fuzzy Analytic Hierarchy Process (FAHP)—resolving the limitation of traditional single evaluation tools and adapting to the dynamic complexity of marine environments. Scientific findings from this framework confirm that hydrogen leakage, high-pressure storage tank valve leakage, and inverter overload are the three most critical failure modes, with hydrogen leakage being the primary risk source due to its high severity and detection difficulty. Further hazard matrix analysis reveals two key risk mechanisms: one type of failure (e.g., insufficient hydrogen concentration) features “high severity but low detectability,” requiring real-time monitoring; the other (e.g., distribution board tripping) shows “high frequency but controllable impact,” calling for optimized operations. This classification provides a theoretical basis for precise risk prevention. Targeted improvement measures (e.g., dual-sealed valves, redundant cooling circuits, AI-based regulation) are proposed and quantitatively validated, reducing the system’s overall risk value from 4.8 (moderate risk) to 1.8 (low risk). This study’s core contribution lies in developing a universally applicable scientific framework for marine hydrogen propulsion system risk assessment. It not only fills the methodological gap in traditional evaluations but also provides a theoretical basis for the safe promotion of hydrogen shipping, supporting the scientific realization of the IMO’s decarbonization goal. Full article

The decarbonization of shipping and shipbuilding is a critical challenge under the Inter-national Maritime Organization’s (IMO) 2030 greenhouse gas (GHG) reduction target and 2050 net-zero strategy, requiring effective coordination between policy and technology. This study investigates how Japan, China, and Korea respond to these regulatory pressures by systematically analyzing their policy–technology linkages. A four-stage design was applied, combining qualitative case studies, policy–technology mapping, theoretical interpretation, and comparative analysis, to trace how national strategies shape eco-friendly transitions. Japan employs an innovation-led, institution-convergent model in which technological demonstrations drive institutional adaptation and diffusion, China follows a policy-designated, execution-oriented model where state-led interventions accelerate commercialization, and Korea adopts a coordination-based, cyclical model balancing public demonstrations, financial support, and international standardization to reduce transition costs. These findings demonstrate that sequencing between policy–technology linkage is context-dependent, shaped by technological maturity, economic feasibility and infrastructure, institutional predictability, and socio-environmental acceptance. The study contributes a cyclic co-evolutionary perspective that moves beyond technological or institutional determinism, reconceptualizes regulation as enabling infra-structure, and identifies implications for global standard-setting and industrial competitiveness. The insights inform practical strategies for major shipbuilding nations to reduce costs while sustaining competitiveness under the IMO’s decarbonization framework. Full article

With the rapid increase in global trade in recent years, the demand for maritime transportation has significantly intensified vessel activity, leading to a considerable rise in carbon emissions originating from the maritime sector. As a result, in line with the 2050 decarbonization targets set by the International Maritime Organization (IMO) and the European Union (EU), legal regulations addressing carbon emissions have been dynamically tightened and gradually enacted. This study aims to determine the significance levels of the factors affecting the maritime sector in response to carbon emission regulations and to reveal the interrelationships among these factors. In this context, the criteria regarding the impacts of climate-related carbon emission regulations were identified based on expert opinions using the Fuzzy Delphi method. The interaction strengths and significance levels among the factors were analyzed using the Fuzzy DEMATEL method, and the relationships were modeled through Interpretive Structural Modeling (ISM). According to the findings, “Fuel Preferences and Alternative Fuel Usage” (C2) emerged as the most critical factor under recent international regulations. “Adaptation to International and National Regulations” (C8) and “Port Infrastructure” (C3) were also identified as the key factors impacting shipping industry efficiency. The analysis revealed that “Logistics Costs” (C5) and “Environmental Protection and Sustainability” (C7) are the most significantly affected outcome factors within the system. The hierarchical structural modeling revealed that “Port Infrastructure” (C3) serves as a defining starting point within the system. This study contributes to the literature by uncovering the causal relationships among the factors determining the effectiveness of ever-evolving carbon emission regulations. It offers a valuable decision-support tool for maritime companies and policymakers. Accordingly, it provides an alternative roadmap and a structural model indicating which strategic areas should be prioritized to achieve the targeted low-carbon emission goals in maritime transportation. Full article

The shipping industry remains heavily dependent on heavy fuel oils, which account for approximately 77% of fuel consumption and contribute significantly to greenhouse gas (GHG) emissions. In line with the IMO’s decarbonization targets, ammonia has emerged as a promising carbon-free alternative. This study evaluates the strategic viability of ammonia, especially green production, as a marine fuel through a hybrid SWOT–Best–Worst Method (BWM) analysis, combining literature insights with expert judgment. Data were collected from 17 maritime professionals with an average of 15.7 years of experience, ensuring robust sectoral representation and methodological consistency. The results highlight that opportunities hold the greatest weight (0.352), particularly the criteria “mandatory carbon-free by 2050” (O3:0.106) and “ammonia–hydrogen climate solution” (O2:0.080). Weaknesses rank second (0.270), with “higher toxicity than other marine fuels” (W5:0.077) as the most critical concern. Strengths (0.242) underscore ammonia’s advantage as a “carbon-free and sulfur-free fuel” (S1:0.078), while threats (0.137) remain less influential, though “costly green ammonia” (T3:0.035) and “uncertainty of green ammonia” (T1:0.034) present notable risks. Overall, the analysis suggests that regulatory imperatives and environmental benefits outweigh safety, technical, and economic challenges. Ammonia demonstrates strong potential to serve as viable marine fuel in achieving the maritime sector’s long-term decarbonization goals. Full article

Environmental emissions from the maritime sector, including CO₂, NO_x, and SO_x, contribute significantly to global air pollution and climate change. The International Maritime Organization (IMO) has set a target to reduce greenhouse gas emissions from international shipping to reach zero GHG by 2050 compared to 2008 levels. To meet these goals, the IMO strongly encourages the transition to alternative fuels, such as hydrogen, ammonia, and biofuels, as part of a broader decarbonization strategy. This study presents a comparative analysis of converting conventional diesel engines to dual-fuel systems utilizing alternative fuels such as methanol or natural gas. The methodology of this research is based on theoretical calculations to estimate various types of emissions produced by conventional marine fuels. These results are then compared with the emissions generated when using methanol and natural gas in dual-fuel engines. The analysis is conducted using the EVER ALOT container ship as a case study. The evaluation focuses on both environmental and economic aspects of engines operating in natural gas–diesel and methanol–diesel dual-fuel modes. The results show that using 89% natural gas in a dual fuel engine reduces nitrogen oxides (NO_x), sulfur oxides (SO_x), carbon dioxide (CO₂), particulate matter (PM), and carbon monoxide (CO) pollutions by 77.69%, 89.00%, 18.17%, 89.00%, and 30.51%, respectively, while the emissions percentage will be 77.78%, 91.00%, 54.67%, 91.00%, and 55.90%, in order, when using methanol as a dual fuel with percentage 91.00% Methanol. This study is significant as it highlights the potential of natural gas and methanol as viable alternative fuels for reducing harmful emissions in the maritime sector. The shift toward these cleaner fuels could play a crucial role in supporting the maritime industry’s transition to low-emission operations, aligning with global environmental regulations and sustainability goals. Full article

Meeting the International Maritime Organization’s (IMO) 2050 targets for reducing greenhouse gas (GHG) emissions requires cost-effective solutions that minimize wind resistance without compromising safety, particularly for medium-sized multipurpose vessels (MPVs), which have been underrepresented in prior research. This study numerically evaluates 20 bow-mounted NaviScreen configurations using a coupled high-fidelity computational fluid dynamics (CFD) and finite element analysis (FEA) approach. Key design variables—including contact angle (35–50°), lower-edge height (1.2–2.0 m), and horn position (3.2–5.3 m)—were systematically varied. The sloped Type-15 shield reduced aerodynamic resistance by 17.1% in headwinds and 24.5% at a 30° yaw, lowering total hull resistance by up to 8.9%. Nonlinear FEA under combined dead weight, wind loads, and Korean Register (KR) green-water pressure revealed local buckling risks, which were mitigated by adding carling stiffeners and increasing plate thickness from 6 mm to 8 mm. The reinforced design satisfied KR yield limits, ABS buckling factors (>1.0), and NORSOK displacement criteria (L/100), confirming structural robustness. This dual-framework approach demonstrates the viability of NaviScreens as passive aerodynamic devices that enhance fuel efficiency and reduce GHG emissions, aligning with global efforts to address climate change by targeting not only CO2 but also other harmful emissions (e.g., NOx, SOx) regulated under MARPOL. The study delivers a validated CFD-FEA workflow to optimize performance and safety, offering shipbuilders a scalable solution for MPVs and related vessel classes to meet IMO’s GHG reduction goals. Full article

The International Maritime Organization (IMO) has set a goal to reach net-zero greenhouse gas emissions from international shipping by or around 2050. The ship energy efficiency framework has played a positive role over the past decade in improving carbon intensity and reducing greenhouse gas emissions by employing the technical and operational energy efficiency metrics as effective appraisal tools. To quantify the ship energy efficiency performance and review the existing energy efficiency framework, this paper analyzed the data for the reporting year of 2023 extracted from the European Union (EU) monitoring, reporting, and verification (MRV) system, and investigated the operational profiles and energy efficiency for the ships calling at EU ports. The results show that the data accumulated in the EU MRV system could provide powerful support for conducting ship energy efficiency appraisals, which could facilitate the formulation of decarbonization policies for global shipping and management decisions for stakeholders. However, data quality, ship operational energy efficiency metrics, and co-existence with the IMO data collection system (DCS) remain issues to be addressed. With the improvement of IMO DCS system and the implementation of IMO Net-Zero Framework, harmonizing the two systems and avoiding duplicated regulation of shipping emissions at the EU and global levels are urgent. Full article

The 83rd session of the IMO Maritime Environment Protection Committee (MEPC 83) approved a global pricing mechanism for the shipping industry, with formal adoption scheduled for October 2025. Proposed mechanisms include the International Maritime Sustainable Fuels and Fund (IMSF&F) and a combined approach integrating GHG Fuel Standards with Universal GHG Contributions (GFS&UGC). This study developed a model based on the marginal abatement cost curve (MACC) methodology to assess the cost-effectiveness of alternative fuels under both mechanisms. Sensitivity analyses evaluated the impacts of fuel prices, carbon prices, and the GHG Fuel Intensity (GFI) indicator on MAC. Results indicate that implementing the GFS&UGC mechanism yields higher net present values (NPVs) and lower MACs compared to IMSF&F. Introducing universal GHG contributions promotes a comparatively fairer transition to sustainable shipping fuels. Investments in zero- or near-zero-fueled (ZNZ) ships are unlikely to be recouped by 2050 unless carbon prices rise sufficiently to boost revenues. Bio-Methanol and bio-diesel emerged as the most cost-competitive ZNZ options in the long term, while e-Methanol’s poor competitiveness stems from its extremely high price. Both pooling costs and universal GHG levies significantly reduce LNG’s economic viability over the study period. MACs demonstrated greater sensitivity to fuel prices (P_fuel) than to carbon prices (P_carbon) or GFI within this study’s parameterization scope, particularly under GFS&UGC. Ratios of P_carbon%/P_fuel% in equivalent sensitivity scenarios were quantified to determine relative price importance. This work provides insights into fuel selection for shipping companies and supports policymakers in designing effective GHG pricing mechanisms. Full article

The accurate prediction of autonomous vessel CO₂ emissions is critical for achieving IMO 2050 carbon neutrality and optimizing low-carbon maritime operations. Traditional models face limitations in real-time multi-source data analysis and dynamic cross-variable dependency modeling, hindering data-driven decision-making for sustainable autonomous shipping. This study proposes a Multi-scale Channel-aligned Transformer (MCAT) model, integrated with a 5G–satellite–IoT communication architecture, to address these challenges. The MCAT model employs multi-scale token reconstruction and a dual-level attention mechanism, effectively capturing spatiotemporal dependencies in heterogeneous data streams (AIS, sensors, weather) while suppressing high-frequency noise. To enable seamless data collaboration, a hybrid transmission framework combining satellite (Inmarsat/Iridium), 5G URLLC slicing, and industrial Ethernet is designed, achieving ultra-low latency (10 ms) and nanosecond-level synchronization via IEEE 1588v2. Validated on a 22-dimensional real autonomous vessel dataset, MCAT reduces prediction errors by 12.5% MAE and 24% MSE compared to state-of-the-art methods, demonstrating superior robustness under noisy scenarios. Furthermore, the proposed architecture supports smart autonomous shipping solutions by providing demonstrably interpretable emission insights through its dual-level attention mechanism (visualized via attention maps) for route optimization, fuel efficiency enhancement, and compliance with CII regulations. This research bridges AI-driven predictive analytics with green autonomous shipping technologies, offering a scalable framework for digitalized and sustainable maritime operations. Full article

In response to global concerns about climate change and decarbonization across every sector, pressure has mounted on the maritime industry to reduce its environmental impacts, specifically its greenhouse gas (GHG) emissions, representing around 2.8% of the global total. As such, it prompts new alternative fuels that align with the International Maritime Organization (IMO)’s 2050 net-zero target. In recent years, several alternative fuels, such as hydrogen, ammonia, and methanol, have been proposed. However, alternative fuels face many challenges regarding cost, safety, and efficiency compared to traditional fossil fuels. Currently, methanol is considered one of the most promising alternatives since it is available, easy to store, and can take full advantage of existing infrastructure in situ. Moreover, methanol has a lower carbon intensity than conventional fossil fuels. However, its usage poses related risks of toxicity and flammability; thus, this area still needs in-depth research regarding hazard control. This study implements a systematic five-step methodology. Through a comprehensive literature review, the predominant hazards are delineated. To systematically analyze these risks, this study introduces a novel hazard-based coding system developed to categorize hazards into three classifications: toxicity, flammability, and explosivity. This system is specifically designed to analyze qualitative reports from thirty methanol accident investigations utilizing MAXQDA software. Subsequently, safety barriers related to methanol are identified, followed by a gap analysis to evaluate the effectiveness of existing safety measures. The findings indicate that physical hazards, including flammability and explosivity, represented the majority of identified risks. Furthermore, tank explosions emerged as a prominent sub-hazard, frequently linked to the highest number of reported fatalities. A gap analysis delineates the identified barriers related to Equipment and Personal Protective Equipment (PPE), Human Error Reduction, the Legal Framework, and First Aid, comparing them against the current measures outlined in IMO Circular 1621 and other legislative frameworks. Consequently, the analysis highlights critical gaps in technical guidelines and operational procedures related to methanol use. The study recommends the development of fuel-specific safety protocols, mandatory training for seafarers, and regulatory updates to address the unique hazards of methanol. These measures are necessary to create higher safety standards and make methanol a viable alternative fuel by ensuring its safe integration into the industry. Full article

Maritime transport carries over 80% of global trade by volume and remains the most energy-efficient mode for long-distance goods movement. However, the sector contributes approximately 3% of global Greenhouse Gas (GHG) emissions, a share that could rise to 17% by 2050 without effective regulation. In response, the International Maritime Organization (IMO) has introduced initial and short-term measures to enhance energy efficiency and reduce emissions. In 2023, IMO Strategy expanded on these efforts with medium-term measures, including Market-Based Mechanisms (MBMs) such as a GHG levy, a feebate system, and fuel intensity regulations combined with carbon pricing. This study evaluates the economic and environmental impacts of these measures using an integrated computational simulation model that combines Ocean Engineering and Economics. Our results indicate that all proposed measures support the IMO’s intermediate emission reduction targets through 2035, cutting absolute emissions by more than 50%. However, economic impacts vary significantly across regions, with most of Africa, Asia, and South America experiencing the greatest adverse effects on GDP and trade. Among the measures, the GHG levy exerts the strongest pressure on economic activity and food prices, while a revised fuel intensity mechanism imposes lower costs, particularly in the short term. Revenue redistribution mitigates GDP losses but does so unevenly across regions. By leveraging a general equilibrium model (GTAP) to capture indirect effects often overlooked in prior studies, this analysis provides a comprehensive comparison of policy impacts. The findings underscore the need for equitable and pragmatic decarbonization strategies in the maritime sector, contributing to ongoing IMO policy discussions. Full article

The transition to environmentally sustainable maritime operations has gained urgency with the International Maritime Organization’s (IMO) 2023 GHG reduction strategy, aiming for net-zero emissions by 2050. While alternative fuels like LNG and methanol serve as transitional solutions, lithium-ion battery energy storage systems (ESSs) offer a viable low-emission alternative. However, safety concerns such as thermal runaway, overcharging, and internal faults pose significant risks to marine battery systems. This study presents an AI-based fault prediction algorithm to enhance the safety and reliability of lithium-ion battery systems used in electric propulsion ships. The research employs a Long Short-Term Memory (LSTM)-based predictive model, integrating electrochemical impedance spectroscopy (EIS) data and voltage deviation analyses to identify failure patterns. Bayesian optimization is applied to fine-tune hyperparameters, ensuring high predictive accuracy. Additionally, a recursive multi-step prediction model is developed to anticipate long-term battery performance trends. The proposed algorithm effectively detects voltage deviations and pre-emptively predicts battery failures, mitigating fire hazards and ensuring operational stability. The findings support the development of safer and more reliable energy storage solutions, contributing to the broader adoption of electric propulsion in maritime applications. Full article

The International Maritime Organization (IMO) is the regulator for the safety and pollution prevention of ships. They have set an ambitious target of driving International Shipping to achieve net-zero greenhouse gas (GHG) emissions in 2050 by the process of decarbonization of shipping. Decarbonization of shipping is integral to sustainability, as it can reduce GHG emissions and provide a clean environment in a world that is conducive to the good health and well-being of our future kith and kin. Decarbonization of shipping may be achieved using alternate low-carbon fuels, a more efficient ship operation to save energy, or redesigning the ship’s hull. The purpose of this article is to conduct a bibliometric analysis of the research papers conducted in the past decade on the initiatives adopted by the shipping industry to work towards the net-zero goal. This study utilizes the Scopus database, renowned for its extensive collection of scientific papers. Moreover, to analyze and visualize the data, the bibliometric software tools VOSviewer 1.6.20, Bibliometrix 4.4.0, and Harzings’ 8.17.4863 have been used. These tools facilitated the assessment of the research output in this bibliometric study. Our findings reveal a steady increase in publications over the years, with a notable rise in research interest from 2015 onward. The most frequently discussed topics include greenhouse gases, emission control, and energy efficiency, with notable contributions from the United Kingdom, China, and Scandinavian countries. The study also highlights the leading journals publishing about this research area. Future research directions include exploring alternative fuels and more inclusive policy frameworks for maritime decarbonization. Full article