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Fuel costs are the sigle most important driver of marginal costs for commercial marine transportation and account for almost 50% of total voyage costs for typical configurations. Hence, there has developed a desire among operators and manufacturers of all classes of ships to embrace innovative ways to reduce the demand for fuels. This research investigates the fuel consumption of a standard container ship architecture based on different scenarios of operation. The approach is to first model fuel consumption from the main propulsion engines and the auxiliary engines based on standard propulsion modes, with a configuration known as a Power Take Off (PTO) system. These preliminary results are then analyzed to identify opportunities for retrofitting this configuration by utilizing the same engine combination, but augmenting the PTO system into a modernized shaft motor-generator system, or Auxiliary Power System (APS). The APS enables electrification, which can potentially decrease system fuel consumption. Lastly, the potential for these fuel savings is evaluated for multiple scales of the APS.

Materials sustainability requires a concerted change in philosophy across the entire materials lifecycle, orienting around the theme of materials stewardship. In this paper, we address the opportunities for improved materials conservation through dematerialization, durability, design for second life, and diversion of waste streams through industrial symbiosis.

The marine transportation industry is a significant contributor to global emissions of CO2 and other pollutants. Although marine emission standards have become increasingly stringent, increasing fuel efficiency remains the primary objective in terms of further reducing emissions and overall marine energy use. In this paper, a hybrid powertrain is investigated as a means of increasing fuel efficiency for a modern, 100 m class, passenger vessel. The hybrid powertrain includes an Energy Storage System (ESS) based on sodium sulfur (NaS) batteries and commercially available Caterpillar diesel engine-generator sets. The ship’s power load profile is based on annual averages for similar vessels. A control strategy and simulation models are developed and implemented in Simulink to analyze the power and energy flows in the hybrid powertrain. The Simulink model is used to compare the base scenario of a ship without energy storage to a hybrid scenario employing a 7.5 MWh NaS battery pack with related control strategy. Annual fuel consumption is the primary measure that is used to assess efficiency. Unlike hybrid powertrains for light-duty surface vehicle transportation, which achieve efficiency gains on the order of 10–20% [8, 9, 10], the hybrid powertrain for a large ship is estimated to lower annual fuel consumption by approximately 2%. The surprisingly small level of fuel savings is explained largely by the granularity of marine power systems, which include multiple generators that can be switched on and off to maximize fuel efficiency.

topside and subsea systems enjoy the same benefits (increased efficiency and reduced costs), yet for different reasons. Oil and gas stakeholders must determine when and where hybrid-power systems provide the most value for operations, how they should be implemented, what technologies are acceptable, what safety considerations there may be, system suitability for extreme environments, and how these technologies can improve the bottom line.There is a wealth of information on Li-ion batteries, though it is not all consistent-cost data are unclear, lifetime and energy density considerations vary under different conditions, and ruggedness and application to harsh environments constitute a large uncertainty. In the following sections, we will address these issues to help provide clarification for the oil and gas operator. SummaryFrom prior experience in the automotive sector, and now the maritime sector, hybridization of power systems is known to increase energy efficiency and reduce emissions, with lower fuel consumption. With impending emissions-control areas in the US continental shelf, and nitrogen oxide enforcement mechanisms in the North Sea, emissions reduction in oil and gas exploration-and-production operations is increasingly relevant. Hybrid-power systems can address some of these issues with batteries to offset peak loads, thereby reducing size requirements for the total system. The challenge that the oil and gas industry faces is to decide when and where hybrid-power systems provide the most value for operations, how they should be implemented, what technologies are acceptable, what safety considerations there may be, and how these technologies can improve the bottom line.There is a wealth of information on lithium-ion batteries, though it is not all consistent-cost data are unclear, lifetime and energy density considerations vary under different conditions, and ruggedness and application to harsh environments constitute a large uncertainty. A review of these technologies is provided to serve as a selection guide.