This paper looks at the implications of various maritime emissions reductions policies for maritime logistics. There can be important trade-offs that have to be made between the environmental benefits associated with such measures as reduction in steaming speed and change in the number of vessels in the fleet, and more conventional logistics attributes such as in-transit inventory holdings.

Balancing the economic and environmental performance of maritime transportation (vol 15, pg 458, 2010)

There has been mounting concerns over energy consumption and environmental impacts due to an increase in worldwide shipping activities. The International Maritime Organization has adopted regulations to impose limits on greenhouse gas emissions originated from fuel combustion of marine vessels. Such regulations are introduced in terms of energy efficiency design index and energy efficiency operational indicator. Extensive electrification of ship propulsion and shipboard power systems has been vastly proposed in the literature to make onboard energy systems more efficient. However, energy efficiency in the context of maritime transport is becoming even more stringent. Various technologies and operational practices therefore are being proposed to ensure full compliance with the tightening restrictions. The methods to increase energy efficiency and environmental performance of all-electric ships to satisfy such requirements involve integration of energy storage with a contribution of intelligent power management to optimize power split between various power generation sources; a tendency toward DC power distribution due to eliminating the need of all generators to be synchronized at a specific frequency; installation of unconventional propulsors for greater maneuverability requirements while keeping fuel consumption low; adoption of low carbon content fuel like liquefied natural gas for dual fuel diesel electric propulsion; establishment of onboard renewable energy systems for alternative clean power options; fuel cell integration in complementary operation with conventional diesel generators. This paper identifies promising technologies and practices that are applicable to onboard energy systems of all-electric ships and also reveals energy efficiency sensitivity of all-electric ships to different applications. The proposed strategies should be eventually combined with alternative technology-based and operational-based measures as implemented on conventional propulsion ships in order to realize full potential for energy efficient operation.

Energy efficiency of integrated electric propulsion for ships – A review

As a highly efficient mode of freight transport for global trade, international shipping is currently expected to improve energy efficiency and reduce carbon emissions. Various countermeasures and action plans have been proposed by stakeholders in the maritime community. This paper presents a comprehensive review to categorise the pathways and highlight the concepts, methodologies, characteristics, implementation barriers and future prospects of different abatement measures for carbon dioxide emissions in the maritime industry. In addition, the regulatory framework composed of rules and regulations, market-based measures and voluntary actions is reviewed and discussed. The literature reviewed is selective and critical considering papers from reputable journals and reports from leading institutions or organisations. It was found that most of the technological and operational measures were highly context-sensitive and no individual measure in isolation could achieve the objectives of low carbon or zero carbon shipping. Eco-friendly fuels and alternative power sources were found to be promising but their applications would significantly depend on ship types and ship routes, i.e., diversification and decentralization of ship power sources and marine fuel types are inevitable for future shipping. It was also shown that the economic considerations and legal framework are still the main challenges at present. This review has clarified the pathways to decarbonisation in the shipping industry and it is expected to be a useful resource for academic research and industrial practice.

A comprehensive review on countermeasures for CO2 emissions from ships

Speed optimization of a container ship on a given route considering voluntary speed loss and emissions

Ship voyage optimization provides key theoretical and technical insights for efficient shipping operations. It is critical for developing methodologies and systems that bridge the gaps between the perceived expectations of stakeholders and actual ship operations and for truly applying primary principles and fundamental practices in maritime operations. To develop an advanced and effective shipping voyage optimization system, it is necessary to investigate thoroughly the factors affecting fuel consumption and integrate wisely other aspects, including cargo operation, emissions from fuel consumption, and emission control regulations. The literature on ship voyage optimization is flourishing with the development of green maritime transportation . This paper carefully reviews the latest articles on emission control-driven voyage optimization to investigate the state-of-art and further identify research gaps, ongoing topics, and future research trends.

Nan Xu

Papers

Model of speed optimization of oil tanker with irregular winds and waves for given route

Investigation on the chemical equilibrium products for CnHmOlNk type fuels using equilibrium constants database