Search Results (10)

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

This study presents an integrated techno-economic and environmental assessment of shaft generator (SG) integration in marine propulsion systems using alternative fuels. A comprehensive numerical model is developed to simulate the operation of a bulk carrier equipped with a low-speed two-stroke main engine, comparing conventional diesel generator (DG) configurations with SG-powered alternatives under varying ship speeds and auxiliary electrical loads. Three fuel types, heavy fuel oil (HFO), fatty acid methyl esters (FAMEs), and methanol–diesel dual fuel, are analyzed to evaluate fuel consumption, exhaust emissions, and economic feasibility. The results show that SG integration consistently reduces total fuel consumption by 0.1–0.5 t/day, depending on load and fuel type, yielding annual savings of up to 150 tonnes per vessel. Carbon dioxide (CO₂), Nitrogen oxide (NO_x), and sulphur oxide (SO_x) emissions decrease proportionally with increased SG load, with annual reductions exceeding 450 tonnes of CO₂ and up to 15 tonnes of NO_x for HFO systems. Methanol–diesel operation achieves the highest relative improvement, with up to 50% lower CO₂ and near-zero SO_x emissions, despite a moderate increase in total fuel mass due to methanol’s lower calorific value. Economically, SG utilization provides daily fuel cost savings ranging from $200 to $1050, depending on the fuel and load, leading to annual reductions of up to $320,000 for high-load operations. The investment analysis confirms the financial viability of SG installations, with net present values (NPVs) up to $1.4 million, internal rates of return (IRRs) exceeding 100%, and payback periods below one year at 600 kW load. The results highlight the dual benefit of SG technology, enhancing energy efficiency and supporting IMO decarbonization goals, particularly when coupled with low-carbon fuels such as methanol. The developed computational framework provides a practical decision-support tool for ship designers and operators to quantify SG performance, optimize energy management, and evaluate the long-term economic and environmental trade-offs of fuel transition pathways. 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

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

With the global maritime industry accelerating toward carbon neutrality, the adoption of alternative marine fuels has emerged as a pivotal pathway for achieving net-zero emissions. To identify the most promising fuel transition solution for multi-purpose heavy-lift vessels (MPHLVs), which are widely used for transporting large and complex industrial equipment and have specialized structural requirements, this study conducted a comprehensive techno-economic analysis based on a fleet of 12 MPHLVs. An eight-dimensional technical adaptability framework was established, and six types of marine fuel were evaluated. Concurrently, a total cost assessment model was developed using 2024 operational data of the fleet, incorporating the fuel procurement, the carbon allowances under the EU ETS, the FuelEU Maritime compliance costs, and the IMO Net-Zero penalties. The results show that methanol as an alternative fuel is the most compatible decarbonization pathway for this specialized vessel type. A case study of a 38,000 DWT methanol-fueled MPHLV further demonstrates engineering feasibility with minimal impact on cargo capacity, and validates methanol’s potential as a technically viable and strategically transitional fuel for MPHLVs, particularly in the context of stricter international decarbonization regulations. The proposed evaluation framework and engineering application offer practical guidance for fuel selection, ship design, and retrofit planning, supporting the broader goal of accelerating low-carbon development in heavy-lift shipping sector. 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

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

This research paper presents an effective approach to reducing marine pollution and costs by determining the optimal marine alternative fuels framework for short-sea shipping vessels, with a focus on energy efficiency. Employing mathematical models in a Python environment, the analyses are tailored specifically for conventional and fully autonomous high-speed passenger ferries (HSPFs) and tugboats, utilizing bottom-up methodologies, ship operating phases, and the global warming potential approach. The study aims to identify the optimal marine fuel that offers the highest Net Present Value (NPV) and minimal emissions, aligning with International Maritime Organization (IMO) regulations and environmental objectives. Data from the ship’s Automatic Identification System (AIS), along with specifications and port information, were integrated to assess power, energy, and fuel consumption, incorporating parameters of proposed marine alternative fuels. This study examines key performance indicators (KPIs) for marine alternative fuels used in both conventional and autonomous vessels, specifically analyzing total mass emission rate (TMER), total global warming potential (TGWP), total environmental impact (TEI), total environmental damage cost (TEDC), and NPV. The results show that hydrogen (H2-Ren, H2-F) fuels and electric options produce zero emissions, while traditional fuels like HFO and MDO exhibit the highest TMER. Sensitivity and stochastic analyses identify critical input variables affecting NPV, such as fuel costs, emission costs, and vessel speed. Findings indicate that LNG consistently yields the highest NPV, particularly for autonomous vessels, suggesting economic advantages and reduced emissions. These insights are crucial for optimizing fuel selection and operational strategies in marine transportation and offer valuable guidance for decision-making and investment in the marine sector, ensuring regulatory compliance and environmental sustainability. Full article

To achieve net zero emissions from ships by 2050 and align with the IMO 2023 GHG strategy, the maritime industry must significantly increase zero-emission vessels by 2030. Transitioning to fully electric ferry lines requires enhanced energy supply through renewable energy sources (RES) for complete GHG mitigation and net-zero emissions. This study presents a GIS-based framework for optimally selecting offshore wind farm locations to meet the energy demands of electric ferry operations along coastal routes. The framework involves two stages: designing feasible zero-emission ferry routes between islands or to the mainland and identifying optimal offshore wind farm sites by evaluating technical, spatial, economic, social, and environmental criteria based on national legislation and the academic literature. The aim is to create a flexible framework to support decision making for establishing sustainable electric ferry operations at a regional level, backed by strategically located offshore wind farms. The study applies this framework to the Greek Coastal Shipping Network, focusing on areas with potential for future electrification. The findings can aid policymakers in utilizing spatial decision support systems (SDSS) to enhance efficient transportation and develop sustainable island communities. Full article