Media: Paper


A Comparative Analysis of Optimal Operation Scenarios in Hybrid Emission-Free Ferry Ships

Banaei, Mohsen; Rafiei, Mehdi; Boudjadar, Jalil; Khooban, Mohammad Hassan

The utilization of green energy resources for supplying energy to ships in the marine industry has received increasing attention during the last years, where different green resource combinations and control strategies have been used. This article considers a ferry ship supplied by fuel cells (FCs) and batteries as the main sources of ship's power. Based on the designers' and owners' preferences, different scenarios can be considered for managing the operation of the FCs and batteries in all-electric marine power systems. In this article, while considering different constraints of the system, six operating scenarios for the set of FCs and batteries are proposed. Impacts of each proposed scenario on the optimal daily scheduling of FCs and batteries and operation costs of the ship are calculated using a mixed-integer nonlinear programming model. Model predictive control (MPC) is also applied to consider the deviations from hourly forecast demand. Moreover, since the efficiency of FCs varies for different output powers, the impacts of applying a linear model for FCs' efficiency are compared with the proposed nonlinear model and its related deviations from the optimal operation of the ship are investigated. The proposed model is solved by GAMS software using actual system data and the simulation results are discussed. Finally, detailed real-time hardware-in-the-loop (HiL) simulation outcomes and comparative analysis are presented to confirm the adaptation capability of the proposed strategy.

IEEE Transactions on Transportation Electrification ( Volume: 6, Issue: 1, March 2020) / 2020
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Energy Management of a Zero-Emission Ferry Boat With a Fuel-Cell-Based Hybrid Energy System: Feasibility Assessment

Rafiei, Mehdi; Boudjadar, Jalil; Khooban, Mohammad Hassan

Due to the increasing impacts of ships pollutants on the environment and the preventive laws that are tightening every day, the utilization of all-electric ships is a recent emerging technology. Being a promising technology, the usage of fuel cells as the main energy resource of marine vessels is an interesting choice. In this article, an all-electric hybrid energy system with zero emission based on fuel cell, battery, and cold-ironing is proposed and analyzed. To this end, actual data of a ferry boat, including load profiles and paths, are considered to assess the feasibility of the proposed energy system. The configuration of the boat and energy resources as well as the problem constraints are modeled and analyzed. Finally, the boat's energy management in hourly form for a one-day period is implemented. The improved sine cosine algorithm is used for the power dispatch optimization, and all models are implemented in MATLAB software. Based on the analysis results, the proposed hybrid system and the energy management method have high performance as an applicable method for the marine vessels. In addition, to be a zero-emission ship, the proposed system has an acceptable energy cost.

IEEE Transactions on Industrial Electronics ( Volume: 68, Issue: 2, Feb. 2021) / 2020
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Benefit of speed reduction for ships in different weather conditions

Taskar, Bhushan; Andersen, Poul

Currently, the shipping industry is facing a great challenge of reducing emissions. Reducing ship speeds will reduce the emissions in the immediate future with no additional infrastructure. However, a detailed investigation is required to verify the claim that a 10% speed reduction would lead to 19% fuel savings (Faber et al., 2012).

This paper investigates fuel savings due to speed reduction using detailed modeling of ship performance. Three container ships, two bulk carriers, and one tanker, representative of the shipping fleet, have been designed. Voyages have been simulated by modeling calm water resistance, wave resistance, propulsion efficiency, and engine limits. Six ships have been simulated in various weather conditions at different speeds. Potential fuel savings have been estimated for a range of speed reductions in realistic weather.

It is concluded that the common assumption of cubic speed-power relation can cause a significant error in the estimation of bunker consumption. Simulations in different seasons have revealed that fuel savings due to speed reduction are highly weather dependent. Therefore, a simple way to include the effect of weather in shipping transport models has been proposed.

Speed reduction can lead to an increase in the number of ships to fulfill the transport demand. Therefore, the emission reduction potential of speed reduction strategy, after accounting for the additional ships, has been studied. Surprisingly, when the speed is reduced by 30%, fuel savings vary from 2% to 45% depending on ship type, size and weather conditions. Fuel savings further reduce when the auxiliary engines are considered.

Transportation Research Part D: Transport and Environment, Volume 85 / 2020
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Cargo allocation and vessel scheduling on liner shipping with synchronization of transshipments

Ozcan, Sel; Eliiyi, D. T.; Reinhardt, Line Blander

A mixed integer linear programming model is presented for the operational level cargo allocation and vessel scheduling problem of a liner shipping company in Turkey, where flow-dependent port-stay lengths, transit times and transshipment synchronizations are considered. The proposed model aims to assign shipments to routes to decrease total tardiness and construct partial vessel schedules for establishing coordination with port authorities to comply with the berthing time windows. In addition to the mathematical model, novel valid inequalities and benders decomposition algorithm are implemented. Performance of the developed algorithm is evaluated on real-life problem instances. The results show that benders decomposition with valid inequalities yields the best performance.

Applied Mathematical Modelling, Volume 77 / 2020
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Mapping the Supply Chain of Ship Recycling

Hsuan, Juliana; Parisi, Cristiana

Ship recycling refers to the process of dismantling vessels with the purpose of extracting and recovering materials for reuse, particularly the steel. The aim of this paper is to map the supply chain of ship recycling. This exploratory and qualitative research provides a glimpse on how regulations influence the supply chain management through inter-organizational arrangements. It considers the trade-offs and combinations of financial and sustainable values that, in many ways, determine these inter-organizational arrangements. Preliminary findings show that there are conflicts of interest with the ship recycling stakeholders. Although compliance of regulations should foster better transparency in the supply chain, these regulations have not yet fully embraced social aspects, such as the fact that domestic demand and supply for steel, as well as many jobs, are dependent on this industry. On the contrary, the initiatives to regulate ship recycling might induce negative effects. This paper suggests that transaction costs analysis and the principal agency theory are two complementary theories for analyzing inter-organizational relationships in the supply chain of ship recycling.

Marine Policy, Volume 118 / 2020
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Identifying the Appropriate Governance Model for Green Port Management: Applying Analytic Network Process and Best-worst Methods to Ports in the Indian Ocean Rim

Munim, Ziaul Haque; Sornn-Friese, Henrik; Dushenko, Mariia

This study investigates the appropriate port governance model for implementation of green port management (GPM) practices. Relying on social systems engineering principles, we propose a multi-criteria decision-making (MCDM) framework considering four port governance models and five major GPM practice indicators. We validate the MCDM framework using survey data collected from top management executives of three ports in the Indian Ocean Rim — Bangladesh, Sri Lanka and Tanzania. We compare the Analytic Network Process (ANP) method with more recently developed Best-Worst Method (BWM) in analysis of the MCDM problem of finding the right port governance model for GPM. We collect data using the ANP and BWM survey in January 2019 and August 2019, respectively, from the same respondents. While participating in the study in January 2019, the respondents did not know that they would respond to the same MCDM problem using a different model, which corresponds to a repeated measures experimental design. In both analyses, we find that increasing privatization in port governance would enhance the implementation of GPM practices. Our study furthermore suggests that BWM is a reliable MCDM method with greater applicability than ANP, as it requires significantly lower number of judgement comparisons.

Journal of Cleaner Production, Volume 268 / 2020
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The impact of the Maritime Labor Convention on seafarers’ working and living conditions: an analysis of port state control statistics

Fotteler, Marina Liselotte; Bygvraa, Despena Andrioti; Jensen, Olaf Chresten

The Maritime Labour Convention, 2006 (MLC2006) entered into force in August 2013 and is a milestone for better working and living conditions (WLC) for seafarers. As of March 2020, 96 countries have ratified the MLC2006, covering more than 90% of the world’s shipping fleet. A system of port state control (PSC) allows ratifying countries to inspect any foreign ship arriving in their ports for compliance with the convention. It is intended as a second safety measure for the identification of substandard ships that sail all over the world. Nine regional agreements, so-called Memoranda of Understanding (MoU), have been signed to coordinate and standardize PSC inspections and to increase efficiency by sharing inspections and information. This paper uses public PSC statistics to evaluate the impact of the MLC2006.

A preliminary analysis using registered tonnage and MLC2006 ratification was conducted and seven MoU were selected for the analysis. The annual reports of these MoU have been viewed in September 2019. Numbers on annual inspections, deficiencies and detentions and in particular data for deficiencies related to living and working conditions and certificates and documents, have been extracted and analyzed for the years 2010 to 2017.

Across the eight-year period analyzed, inspection numbers remained stable among all MoU authorities. Deficiencies overall and deficiencies related to WLC declined, indicating an improvement in conditions overall and an increased focus on seafarers’ conditions on board. After the MLC2006 entered into force, three MoU reported WLC-ratios above 14%, while the numbers didn’t rise above 10% in the other four authorities. Deficiencies related to certificates and documents did not rise significantly between 2010 and 2017. Two European MoU showed the highest ratios for deficiencies in both categories analyzed.

The analysis confirmed that an increasing attention is being paid to the inspection of working and living conditions, especially in European countries. However, a clear positive impact of the MLC2006 could not be determined from the PSC statistics in this analysis. A large variation still exists among the MoU, a fact that demands increased efforts for harmonization of PSC procedures.

BMC Public Health, volume 20 / 2020
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Changing Paradigms in the Law of the Sea and the Marine Arctic

Tanaka, Yoshifumi

The existence of a sense of common or community interests is a prerequisite to establishing an order in a society, national or international. In this connection, it is notable that the protection of community interests is increasingly important in international law and the law of the sea is no exception. The increasing need for protecting community interests necessitates a new paradigm in the law of the sea. The legal issues regarding the marine Arctic should also be considered in the context of changing paradigms in the law of the sea. Thus this article seeks to overview principal issues of the international law governing the marine Arctic from the viewpoints of a dual paradigm, that is, the law of divided oceans (paradigm I) and the law of our common ocean (paradigm II).

The International Journal of Marine and Coastal Law, 35(3) / 2020
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Analysis of structural crashworthiness of double-hull ships in collision and grounding

Liu, Bin; Villavicencio, Richard; Pedersen, Preben Terndrup; Guedes Soares, C.

A conceptual design framework for collision and grounding analysis is proposed to evaluate the crashworthiness of double-hull structures. This work attempts to simplify the input parameters needed for the analysis, which can be considered as a step towards a design-oriented procedure against collision and grounding. Four typical collision and grounding scenarios are considered: (1) side structure struck by a bulbous bow, (2) side structure struck by a straight bow, (3) bottom raking, (4) bottom stranding. The analyses of these scenarios are based on statistical data of striking ship dimensions, velocities, collision angles and locations, as well as seabed shapes and sizes, grounding depth and location. The evaluation of the damage extent considers the 50- and 90-percentile values from the statistics of collision and grounding accidents. The external dynamics and internal mechanics are combined to analyse systematically the ship structural damage and energy absorption under accidental loadings.

Marine Structures, Volume 76 / 2020
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Simultaneous energy management and optimal components sizing of a zero-emission ferry boat

Letafat, Armin; Rafiei, Mehdi; Sheikh, Morteza; Afshari-Igder, Mosayeb; Banaei, Mohsen; Boudjadar, Jalil; Khooban, Mohammad Hassan

Due to environmental and economic issues as well as the high performance of marine vessels, efficient energy using has been becoming more demanding. Also, in order to have a zero-emission ship, the utilization of a fuel cell combined with energy storage such as batteries gets more and more attention. In this work, a zero-emission hybrid energy system, including fuel cells, batteries, and cold-ironing, is employed to have an environmentally friendly vessel, and to create condition in which ship operates with high performance, both energy management and components sizing of fuel cells and batteries using real data of ferry boat and intelligent optimization method are done simultaneously. In addition, all constraints related to energy management and component sizing with the topography of the boat and electric power sources are represented and analyzed thoroughly. Ultimately, hourly energy management and component sizing for one specific day are considered in this work, and to optimize this problem, the Improved Sine Cosine Algorithm (ISCA) is utilized. According to obtained results, the proposed energy management and component sizing result in the high-performance ship which could be utilized in the marine industry.

Journal of Energy Storage Volume 28, April 2020, 101215 / 2020
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