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Reflections on the Implications of Environmental Norms for Fishing: The Link between the Regulation of Fishing and the Protection of Marine Biological Diversity

Tanaka, Yoshifumi

The aim of this article is to examine the implications of environmental norms for fishing by analysing the South China Sea and Chagos Marine Protected Area cases. In so doing, the article considers the link between the regulation of fishing and the protection of marine biological diversity. Specifically, three issues are to be examined: (1) the implications of Articles 192 and 194(5) of the UN Convention on the Law of the Sea for the regulation of environmentally harmful fishing, (2) the implications of Article 194 of the Convention for the fishing rights of a state, and (3) balance between environmental considerations and the fishing rights of a state. In this connection, the article argues that environmentally harmful fishing can be regarded as a key concept when considering the regulation of fishing from the viewpoints of marine environmental protection.

International Community Law Review, 22(3-4) / 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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The Logic of Business vs. the Logic of Energy Management Practice: Understanding the Choices and Effects of Energy Consumption Monitoring Systems in Shipping Companies

Taudal Poulsen, René; Johnson, Hannes

A major part of the world fleet of more than 47,000 merchant ships operates under conditions that hamper energy efficiency and efforts to cut CO2 emissions. Valid and reliable data sets on ships' energy consumption are often missing in shipping markets and within shipping organizations, leading to the non-implementation of cost-effective energy efficiency measures. Policy makers are aiming to remedy this, e.g., through the EU Monitoring, Verification and Reporting scheme. In this paper, current practices for energy consumption monitoring in ship operations are explored based on interviews with 55 professionals in 34 shipping organizations in Denmark. Best practices, which require several years to implement, are identified, as are common challenges in implementing such practices—related to data collection, incentives for data misreporting, data analysis problems, as well as feedback and communication problems between ship and shore. This study shows how the logic of good energy consumption monitoring practices conflict with common business practices in shipping companies – e.g., through short-term vessel charters and temporary ship organizations – which in turn can explain the slow adoption of energy efficiency measures in the industry. This study demonstrates a role for policy makers or other third parties in mandating or standardizing good energy consumption monitoring practices beyond the present requirements.

Journal of Cleaner Production, Volume 112 / 2016
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Fuel consumption and emission reduction of marine lean-burn gas engine employing a hybrid propulsion concept

Tavakoli, Sadi; Bagherabadi, Farmyard Maleki; Schramm, Jesper; Pedersen, Eilif

As the emission legislation becomes further constraining, all manufacturers started to fulfill the future regulations about the prime movers in the market. Lean-burn gas engines operating under marine applications are also obligated to enhance the performance with a low emission level. Lean-burn gas engines are expressed as a cleaner source of power in steady loading than diesel engines, while in transient conditions of sea state, the unsteadiness compels the engine to respond differently than in the steady-state. This response leads to higher fuel consumption and an increase in emission formation. In order to improve the stability of the engine in transient conditions, this study presents a concept implementing a hybrid configuration in the propulsion system. An engine model is developed and validated in a range of load and speed by comparing it with the available measured data. The imposed torque into the developed engine model is smoothed out by implementing the hybrid concept, and its influence on emission reduction is discussed. It is shown that with the hybrid propulsion system, the NOX reduces up to 40% because of the maximum load reduction. Moreover, eliminating the low load operation by a Power Take In during incomplete propeller immersion, the methane slip declines significantly due to combustion efficiency enhancement.

International Journal of Engine Research / 2021
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Impacts of short-term measures to decarbonize maritime transport on perishable cargoes

Thalis P. Zis, Harilaos N. Psaraftis

The International Maritime Organization (IMO) has adopted a strategy to reduce emissions from international shipping that sets very ambitious targets. The first set of actions, so-called short-term measures, are expected to be implemented by 2023 and result in a reduction of emission intensity by at least 40% by 2030 compared with 2008 levels. Compliance may be achieved through a reduction in sailing speeds, but certain countries have raised concerns on the ramifications of longer transit times on their exports, particularly for perishable products. In this paper, we present a methodology to assess the impacts of various short-term measures on perishable products. We use an extension of a nested modal split model to examine shifts towards other modes of transport. We demonstrate our methodology with a transpacific case study carrying perishable products from South America to China. We compare the short-term measures currently under discussion, in one of the first academic studies to explore these issues. These include a speed limit approach, a power limit, and a goal-based measure. Our results show that a power limit or a goal-based measure would offer some advantages to liner shipping operators using more efficient vessels, unlike a speed limit. Using 2008 as the benchmark year has resulted in small speed reductions required by the liner shipping sector to reach its targets. For perishable cargoes, small speed reductions can be tolerated by the shippers without significant modal shift. Choosing the right short-term strategy is of utmost importance to promote clean shipping practices in the following years.

Maritime Economics & Logistics / 2021
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Decarbonizing maritime transport: A Ro-Pax case study

Thalis P.V. Zis*, Harilaos N. Psaraftis, Fabian Tillig, Jonas W. Ringsberg

In an effort to reduce carbon emissions from international shipping, the International Maritime Organization (IMO) developed its initial strategy in April 2018 setting ambitious targets for the sector. According to the initial strategy, greenhouse gas (GHG) emissions from international shipping need to be reduced by at least 50% by 2050, and the CO2 emissions intensity by 40% by the year 2030, both compared to the 2008 levels. In order to achieve these goals, a combination of operational measures, investments in emissions abatement technology, and market-based measures will be necessary. The goals currently do not differentiate among different shipping sectors, and each sector faces different challenges. In this paper, we focus on short sea shipping (SSS), and on Ro-Pax services in particular that in general have not been examined thoroughly in the literature. We examine the emissions reduction potential of several measures, and we assess their efficacy compared with the targets set by the IMO initial strategy. The paper shows that the examined measures are not sufficient on their own to achieve the desired levels of reductions, and that a combination will be necessary, while technological solutions will need to be made more competitive through market based instruments.

Research in Transportation Business and Management / 2020
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Design and application of a key performance indicator (KPI) framework for autonomous shipping in Europe

Thalis P.V. Zis, Harilaos N. Psaraftis, Martina Reche-Vilanova

The European Union (EU) transport policy recognizes the importance of the waterborne transport systems as key elements for sustainable growth in Europe. By 2030, 30% of total road freight over 300 km should shift to rail or waterborne transport, and more than 50% by 2050. Thus far, this ambition has failed but there have been several project initiatives within the EU to address these issues. In one of these projects, we consider a new waterborne transport system for Europe that is green, robust, flexible, more automated and autonomous, and able to connect both rural and urban terminals. The purpose of this paper is to describe work and preliminary results from this project. To that effect, and in order to assess any solutions contemplated, a comprehensive set of Key Performance Indicators (KPIs) has been defined, and three specific use cases within Europe are examined and evaluated according to these KPIs. KPIs represent the criteria under which the set of solutions developed are evaluated, and also compared to non-autonomous solutions. They are grouped under economic, environmental and social KPIs. KPIs have been selected after a consultation process involving project partners and external Advisory Group members. Links to EU transport and other regulatory action are also discussed.

Maritime Transport Research / 2023
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Design and application of a key performance indicator (KPI) framework for autonomous shipping in Europe

Thalis P.V. Zis, Harilaos N. Psaraftis, Martina Reche-Vilanova

The European Union (EU) transport policy recognizes the importance of the waterborne transport systems as key elements for sustainable growth in Europe. By 2030, 30% of total road freight over 300 km should shift to rail or waterborne transport, and more than 50% by 2050. Thus far, this ambition has failed but there have been several project initiatives within the EU to address these issues. In one of these projects, we consider a new waterborne transport system for Europe that is green, robust, flexible, more automated and autonomous, and able to connect both rural and urban terminals. The purpose of this paper is to describe work and preliminary results from this project. To that effect, and in order to assess any solutions contemplated, a comprehensive set of Key Performance Indicators (KPIs) has been defined, and three specific use cases within Europe are examined and evaluated according to these KPIs. KPIs represent the criteria under which the set of solutions developed are evaluated, and also compared to non-autonomous solutions. They are grouped under economic, environmental and social KPIs. KPIs have been selected after a consultation process involving project partners and external Advisory Group members. Links to EU transport and other regulatory action are also discussed.

Maritime Transport Research / 2023
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High-fidelity numerical wave tank verification & validation study: Wave generation through paddle motion

Thanh Toan Tran, Brek Meuris, Chris Chartrand, Josh Davidson, Jacob Andersen, Claes Eskilsson, Morten Bech Kramer, George Papadakis & Kim Nielsen

This paper presents a numerical benchmark study of wave propagation due to a paddle motion using different high-fidelity numerical models, which are capable of replicating the nearly actual physical wave tank testing. A full time series of the measured wave generation paddle motion that was used to generate wave propagation in the physical wave tank will be utilized in each of the models contributed by the participants of International Energy Agency Ocean Energy Systems Task 10, which includes both computational fluid dynamics and smoothed particle hydrodynamics models. The high-fidelity simulations of the physical wave test case will allow for the evaluation of the initial transient effects from wave ramp-up and its evolution in the wave tank over time for two representative regular waves with varying levels of nonlinearity. Metrics like the predicted wave surface elevation at select wave probes, wave period, and phase-shift in time will be assessed to evaluate the relative accuracy of numerical models versus experimental data within specified time intervals. These models will serve as a guide for modelers in the wave energy community and provide a base case to allow further and more detailed numerical modeling of the fixed Kramer Sphere Cases under wave excitation force wave tank testing.

CRC Press / 2024
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Estimation of incident and reflected components in nonlinear regular waves over sloping foreshores

Thomas Lykke Andersen & Mads Røge Eldrup

The present paper deals with separation of long-crested regular waves into incident and reflected components. Such methods have been available for several decades for linear waves, but have recently been extended to cover nonlinear waves over horizontal foreshores. The overall goal of the present paper is to extend the separation method for nonlinear regular waves to also cover sloping foreshores. This requires the combination of the existing method with a nonlinear shoaling model. A nonlinear shoaling model was very recently found valid for the shoaling of the primary and bound components in regular waves when the slope angle is positive and mild. In the present paper this shoaling model is utilized and assumed valid also for the de-shoaling of the reflected waves, ie on a negative mild slope angle. However, if the reflected waves are nonlinear the de-shoaling process is much more complicated and will for example cause the release of free waves. Interactions among those free reflected wave components may cause nonlinear interactions not included in the mathematical model. For that reason, the applicability range is limited to mildly nonlinear reflected waves. Using numerical model data with various foreshore slopes, wave nonlinearities and reflection coefficients the reliability of the developed model is examined in detail.

Coastal Engineering / 2021
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