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.
This paper aims to conduct an updated literature survey on the Market-Based Measures (MBMs) currently being proposed by various member states and organizations at the International Maritime Organization (IMO) or by the scientific and grey literature as a cost-effective solution to reduce greenhouse gas (GHG) emissions from ships. Τhe paper collects, summarizes, and categorizes the different proposals to provide a clear understanding of the existing discussions on the field and also identifies the areas of prior investigation in order to prevent duplication and to avoid the future discussion at the IMO to start from scratch. Relevant European Union (EU) action on MBMs is also described. Furthermore, the study identifies inconsistencies, gaps in research, conflicting studies, or unanswered questions that form challenges for the implementation of any environmental policy at a global level for shipping. Finally, by providing foundational knowledge on the topic of MBMs for shipping and by exploring inadequately investigated areas, the study addresses concrete research questions that can be investigated and resolved by the scientific and shipping community
All-electric ships, and especially the hybrid ones with diesel generators and batteries, have attracted the attention of maritime industry in the last years due to their less emission and higher efficiency. The variant emission policies in different sailing areas and the impact of physical and environmental phenomena on ships energy consumption are two interesting and serious concepts in the maritime issues. In this paper, an efficient energy management strategy is proposed for a hybrid vessel that can effectively consider the emission policies and apply the impacts of ship resistant, wind direction and sea state on the ships propulsion. In addition, the possibility and impact of charging and discharging the carried electrical vehicles’ batteries by the ship is investigated. All mentioned matters are mathematically formulated and a general model of the system is extracted. The resulted model and real data are utilized for the proposed energy management strategy. A genetic algorithm is used in MATLAB software to obtain the optimal solution for a specific trip of the ship. Simulation results confirm the effectiveness of the proposed energy management method in economical and reliable operation of the ship considering the different emission control policies and weather condition impacts.
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.
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.
The Common Fisheries Policy (CFP) is rooted in the Treaty of Rome. After its completion in 1983, the policy framework was gradually reformed through decennial reviews in 1993, 2003, and 2014. Due to geopolitical, physiographic, and historical reasons, the EU implementation of the CFP is most developed in the North Atlantic Ocean, the North Sea, and the Baltic Sea, and less developed in the Mediterranean and Black Sea. However, the CFP applies throughout European Union (EU) waters, which that are treated as a “common pond.” The CFP has been heavily contested since its introduction, and over long periods was characterized as a management system in crisis. Historically, the CFP has arguably struggled to perform and the policy’s ability to meet its objectives has not uncommonly been undermined by factors such as internally contradictory decisions and inefficient implementation. Since the turn of the century, the policy has changed its course by incrementally institutionalizing principles for a more environmentally orientated and scientifically based fisheries management approach. In general, in the latest decade, fisheries have become increasingly sustainable in both environmental and economic terms. An increasing number of fish stocks under the CFP are being exploited at sustainable levels—a development that is likely to continue, as fish stocks are coming to be more commonly managed along the lines of science-based multi-annual management plans. Consequently, many fishing fleets, particularly those deployed in northern waters, have shown good economic performance in recent years. This development has been further facilitated by the introduction of market-based management principles; in most member states these have been implemented by granting de facto ownership to fishing rights for free in the name of ecological and economic sustainability. This has, however, in many cases also led to huge wealth generation for a small privileged group of large-scale fishers at the expense of small-scale fisheries and smaller fishing communities, as well as society at large; this situation has led to calls for both a fairer distribution of fishing rights—to protect the small-scale sector—and for a resource rent or exploitation fee to be collected for the benefit of society at large, which is the true owner of fishing resources. Consequently, social sustainability, understood as the improved well-being of fishing communities and a fairer sharing out of the benefits derived from fisheries resources, should be a subject for the CFP to consider in the future.
The profile of small-scale fisheries has been raised through a dedicated target within the United Nations Sustainable Development Goals (SDG14b) that calls for the provision of 'access of small-scale artisanal fishermen to marine resources and markets'. By focusing on access to fisheries resources in the context of the European Union, in this article we demonstrate that the potential for small-scale fishing sectors to benefit from fishing opportunities remains low due to different mechanisms at play including legislative gaps in the Common Fisheries Policy, and long-existing local structures somewhat favoring the status quo of distributive injustice. Consequently, those without access to capital and authority are faced by marginalizing allocation systems, impacting the overall resilience of fishing communities. Achieving SDG14b requires an overhaul in the promulgation of policies emanating from the present nested governance systems.
This paper aims to determine what the proper role of the judiciary should be in developing climate change policy. It does so in light of the sometimes contentious relationship between ‘activist’ or ‘progressive’ judges and the doctrine of separation of powers. This relationship has a long history by which much of human rights law has been shaped. The paper analyses the court judgments in the cases of Urgenda v Kingdom of the Netherlands, Juliana v United States, and Friends of the Irish Environment v Ireland in order to identify how different legal systems view this relationship. The paper also considers the upcoming climate case in the Supreme Court of Norway. In particular, the question is asked whether the separation of powers in Europe and the United States is a doctrine mandating systems of power balance rather than of strict separation.
Drawing on the argumentation from the Urgenda judgment, the paper concludes that the protection and development of human rights should be the main concern in climate change litigation. The judiciary should accordingly take an important role in climate change policy-making in order for the state to comply with its duty to instigate emission limits.
When a ship navigates at sea, the slamming impact can generate significant load pulses which move up along the hull plating. The effect of the moving pressure has so far not been explicitly considered in the Rules and Regulations for the Classification of Ships. Based on a modal superposition method and the Lagrange equation, this paper derives analytical solutions to study the elastic dynamic responses of fully clamped rectangular plates under moving pressure impact loads. The spatial variation of the moving slamming impact pressure is simplified to three types of impact loads, i.e. a rectangular pulse, a linearly decaying pulse and an exponentially decaying pulse. The dynamic responses of fully clamped rectangular plates under the moving slamming impact pressure are calculated in order to investigate the influence of the load pulse shapes and moving speed on the plate structural behaviour. It is found that the structural response of the plate increases with the increase of the moving speed. The response of the plate subjected to a moving pressure impact load is smaller than the case when the plate is subjected to a spatially uniform distributed impact load with the same load amplitude and load duration. In order to quantify the effect of the moving speed on the dynamic load, a Dynamic Moving Load Coefficient (DMLC) is introduced as the ratio between the dynamic load factor for the moving impact load and that under the spatially uniform distributed impact load. An expression for DMLC is proposed based on analyses of various scenarios using the developed analytical model. Finally an empirical formula which transforms the moving impact loads to an equivalent static load is proposed.
BACKGROUND: Fatigue is a recognised risk factor for safety in seafaring. While always dangerous, fatigue in ferry shipping is especially hazardous as it may jeopardise passengers' safety. To counteract fatigue, knowledge on its determinants is important. Little, however, is known on the influence from physical and psychosocial work environment factors within ferry shipping. The aim of the study was to investigate the association between work stress in terms of physical stressors, perceived job demands and job control and different dimensions of fatigue among ferry ship employees and to test whether a potential effect of work stress was mediated by sleep satisfaction. MATERIALS AND METHODS: The design was cross-sectional. 193 respondents answered to a self-administered questionnaire including standardised scales, i.e. the Swedish Occupational Fatigue Inventory and the Copenhagen Psychosocial Questionnaire for job demands and control. The association of risk factors with fatigue was determined using hierarchical multiple linear regression analyses. RESULTS: Physical work stressors were positively associated with only one of five fatigue subscales: lack of energy. Higher levels of demands were related to more lack of energy, lack of motivation, physical exertion and sleepiness, while more control was related to lesser lack of energy, lack of motivation and sleepiness. No demand-control interaction was found. Effects of demand and control were partly mediated by sleep satisfaction. CONCLUSIONS: Although limited by its cross-sectional design this study provides support for the independent relevance of demands and control for employee fatigue in ferry shipping and for a mediating role of sleep satisfaction.