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Electric transportation has been a well-studied research topic with electric ships gaining momentum. Ships can have a wide range in size from small cargo ships to military vessels. The benefits of electrification include meeting environmental sustainability goals and operational benefits in terms of flexibility and renewed operation. The power systems onboard a ship can be considered a microgrid, which is called a shipboard microgrid. This system poses unique challenges compared to land-based microgrids due to the resiliency requirements of being at sea. A control system for a hybrid- electric ship is proposed with both an energy storage system (ESS) and traditional diesel generators and gas turbines. This system balances economics with resilient control by calculating a baseline load distribution using the cost of operating each unit for the expected load profile. Additionally, the control system ensures that the generation capacity is available if the load does not follow the expected profile. To maintain flexibility, the system will redispatch the units as needed based on the actual load applied, while reducing the control efforts and maintaining the generation contingency. Therefore, the proposed shipboard microgrid control offers a control method that considers the cost of operation while maintaining the required standards of shipboard microgrid control. / Electrical and Computer Engineering

Every year the automotive industry strives to increase fuel efficiency in vehicles. When most vehicles are designed, fuel efficiency cannot always come first. The Shell Eco-marathon changes that by challenging students everywhere to develop the most fuel-efficient vehicle possible. There are many different factors that affect fuel efficiency, and different teams focus on different vehicle parameters. Currently, there is no straightforward design tool that can be used to help in Shell Eco-marathon vehicle design. For this reason, it is difficult to optimize every vehicle parameter for maximum fuel efficiency. In this study, a simulation is developed by using basic vehicle models and experimental data to accurately represent any prototype-class vehicle in the Shell Eco-marathon. This simulation is verified using different experimental data from an on-vehicle data acquisition system. An easy-to-use design tool is developed, and this tool is used to optimize driving strategy and final drive ratio to maximize fuel efficiency.

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Intelligent Transportation System (ITS) provides a great platform for the planners to reduce environmental externalities from auto. We now have access to real time data. We have been using shortest path to provide route choice to the user. But we have the potential to add more variables in choosing routes. Real time data can be used to measure carbon di-oxide emission during a trip. Also, fuel efficiency can be measured using the real time data. Planners should use this potential of ITS to reduce the environmental impact. This paper thus try to evaluate if considering three variables shortest path, environmental impact and fuel efficiency together instead of only shortest path will change the route choice or not. It provides case studies on different types of routes and between different sets of origin /destination to evaluate the combined influence of these three variables on route choice.

The transportation sector continues to be a primary source of greenhouse gas (GHG) emissions, contributing more than any other sector in the United States in 2017. Medium-duty and heavy-duty trucks trail only passenger cars as the largest GHG contributor in this sector [1]. The intense operating requirements of these vehicles create a reliance on the diesel engine that is projected to last for many decades. Therefore, it is vital that the efficiency and environmental sustainability of diesel engines continue to be advanced.<br><br>Cylinder deactivation (CDA) is a promising technology to improve diesel engine fuel efficiency and aftertreatment thermal management for emissions reduction. This work presents original experimental results demonstrating fuel efficiency improvements of CDA implemented on a modern engine at idle operating conditions through testing of various CDA configurations. Idle calibration optimizations result in up to 28% fuel consumption reduction at steady-state unloaded idle operation and 0.7% fuel consumption reduction over HD-FTP drive cycles at equivalent emissions levels. The low-load thermal management performance of CDA is also investigated through creep and extended idle transient cycles, during which CDA is shown to reduce fuel consumption by up to 40% with similar thermal management performance and reduced NOx and soot emissions. <br><br>Variants of CDA implementation are explored through an experimental comparison of deactivation strategies. The effort described here compares charge trapping strategies through examination of in-cylinder pressures following deactivation because: (1) choice of trapping strategy dictates the in-cylinder pressure characteristics of the deactivated cylinders, and (2) deactivated cylinders can affect torque, oil consumption, and emissions upon reactivation. Results discussed here suggest no significant differences between the strategies. As an example, the in-cylinder pressures of both trapping strategies are shown to converge as quickly as 0.8 seconds after deactivation.<br><br>Finally, the NVH effects of CDA are characterized through studies of torsional vibration, linear vibration, and acoustics. CDA causes frequency content at reduced frequencies compared to conventional operation, which has effects on all aspects of NVH. This creates possible constraints on achievable fuel efficiency and thermal management performance by restricting CDA usage. An alternate form of CDA, dynamic cylinder activation (DCA), is explored as a possible option of avoiding undesirable frequency output while maintaining the desired engine performance. <br>

Reducing automobile-based gasoline consumption has been a major U.S. public policy issue recently. A key driving force behind policymakers' desire is the concern of environmental externalities and national security. Currently, there are three public policies towards reducing automobile gasoline consumption: raising federal gasoline tax, raising the Corporate Average Fuel Economy (CAFE) Standards and vehicle scrappage subsidies of government to retirement of old vehicles. My research studies the effectiveness of these policies in the United States. Among all polices, economists often argue that higher gasoline tax would be more effective in improving fuel economy efficiency. In my first chapter, I ask how gasoline prices influence households' automobile replacement decisions and thus market fuel economy efficiency, which is measured by average mileage per gallon in a city. I specify and estimate a structural dynamic model of consumer preference for new and used vehicles following the methodology proposed by Gowrisankaran and Rysman (2009). Since gasoline costs accounts for 65% of total operating costs, the current and future gasoline price must need to be taken into consideration for rational forward-looking consumers when they are making vehicle choices. Besides, the replacement decision for vehicles is dynamic as well: facing depreciation as the automobile ages and the improving features for new products, consumers need to decide whether to replace the vehicle in the current period or later. Therefore, a dynamic model of consumer choice would be crucial to correct policy evaluation of fuel economy efficiency, while previous literature fails to consider the dynamics. By taking dynamics into consideration, I am able to capture the inherent dynamic nature of a forward-looking consumer's decision, with rational expectation on the evolution of vehicle attributes and retail gasoline prices. I estimate the model using a rich dataset combing vehicle registration data on different cities, vehicle characteristic data, average gasoline price, etc. Although a high gasoline tax is never put in practice in the U.S. and may not be political feasible, I further conduct an experiment of raising gasoline tax to test how fuel economy efficiency is affected based on my model estimates. Experiments suggest that keeping a $4 gasoline price would result in a steady trend for a city's fleet fuel efficiency increase, while doubling current rate will only increase fuel efficiency in the first several years, but experience drops over time. The Corporate Average Fuel Economy (CAFE) are regulations in the United States that intended to improve the average fuel economy of cars and light trucks sold in the US. However, it is long been realized that with a more fuel efficiency car, consumers may be induced to drive more which partially offsets the original energy saving by the policy. Therefore, to assess the effectiveness of CAFE standards, it is crucial to ask: how fuel economy efficiency, which is measured by mileage per gallon (MPG), affects households' vehicle mileage traveled and its distribution. In my second chapter, I answer the question by estimating a structural model for joint determination of vehicle fuel efficiency choice and vehicle mileage traveled each year with a detailed micro-level data of National Household Travel Survey 2001. I further study the distributional effects on vehicle miles of fuel efficiency using instrumental quantile regression. Comparison on results and tests of weak instruments between my method and literature suggest that my model and choice of instruments provide consistent estimates, while using choice probabilities as instruments is not valid. My results support some earlier findings of rebound effects with a more precise quantitative estimation. In addition, I find new evidence that costs associated with raising CAFE standards vary across different quantiles of annual mileage driven and are especially high for those with below-average vehicle mileage driven. These findings also provide rationale in support of a tax on mileage, which is more effective in reducing gasoline consumptions, comparing to the costs of CAFE standards. My third chapter focus on 2009 CARS Program (Cash-for-Clunker). The 2009 CARS program attempted to boost the sale of new fuel efficient vehicles to replace old gas guzzlers. The program established a two-tier incentive system depending on whether buyers purchased a passenger vehicle or an SUV. The result is that many of the new purchased vehicles are indeed SUVs. The CARS program collected information about the old scrapped vehicles and linked it to the actual purchase of the new vehicles. It is thus possible to analyze the effect of preference inertia in choices by comparing the characteristics of old and new vehicles. The fact that effective prices that consumers face are determined by the mileage class of the old car also allows us to evaluate the distribution of valuation trade-offs between mileage and other characteristics such as size, performance, and vehicle class. My findings suggest that the 2009 Cash-for-Clunker is not very effective in terms of affecting consumers' choice of SUVs and big cars. For transactions under the program, consumers still prefer SUVs and large cars. The extra $1000 rebates actually increase consumers' tastes towards SUVs. / text

This thesis aims at increased knowledge in two fields of tribological research; both related to making currently used combustion engines greener. The first field regards the possibilities of using a boric acid fuel additive to increase fuel efficiency. The second field is about the severe wear phenomenon scuffing, which can become problematic when cargo ships are operated on low-sulphur fuel to reduce sulphuric emissions. Tribological tests were developed and performed to simulate the applications. Advanced surface analysis was performed to understand changes occurring on the outermost surface of sliding components, which affect friction and wear. Samples from engines were studied to verify the relation between the lab tests and the applications. In the case of boric acid, the coefficient of friction was below 0.02 for large parts of the tests, but varied with test parameters. The corresponding reduction in friction was up to 78% compared with tests without the additive. As an attempt to assess if the substantial fuel savings found in field tests with passenger cars (6%) can be explained by friction reduction in boundary and mixed lubricated parts of the piston assembly, assumptions were presented that would lead to fuel savings close to these 6%. Boric acid was detected on surfaces after the tests, and the tribofilm appearance depended on test parameters. The tribofilms were shown to be affected by storage time and test temperature; a finding that is vital for future studies. In the case of scuffing, mechanisms were studied and accumulation of wear debris had a significant role on scuffing initiation in the lab scale scuffing tests. Regarding the possibility to test materials scuffing resistance, there was a large scatter in the results, and thereby difficult to draw conclusions. Two new piston ring materials were identified to perform somewhat better than the currently used. In conclusion, findings that could facilitate immediate improvement of fuel efficiency of today’s combustion engine vehicles as well as findings that strengthen available hypotheses on scuffing mechanisms are presented. The latter offers improved understanding of scuffing and thereby give possibilities to counteract the higher risk associated with operation on cleaner fuel.

With the automotive industry ever striving to push the limits of fuel efficiency, the Shell EcoMarathon offers a glimpse into this energy conserving mindset by challenging engineering students around the world to design and build ultra-efficient vehicles to compete regionally. This requires synchronization of engineering fields to ensure that the vehicle and powertrain system work in parallel to achieve similar goals. The goal for Cal Poly – San Luis Obispo’s EcoMarathon vehicle for the 2015 competition is to analyze the unique operating mode that the powertrain undergoes during competition and improve their current package to increase fuel efficiency. In this study, fuel delivery, ignition timing and engine temperature are experimentally varied to observe trends in steady state fuel consumption. A developmental simulation is then implemented with these trends to analyze potential differences in transient and steady state tuning targets. The engine is then tuned to finalized tuning targets and performance compared with benchmark values.

The present paper describes an innovative electro-hydraulic system developed for automated side loaders. The system is based on Intelligent Flow Control (IFC), a concept where open circuit electric displacement controlled pumps are coupled with EH directional control valves. IFC was selected in order to achieve the level of performance required, in terms of efficiency and productivity (i.e. cycle times), and also to provide the best possible control of the side loader arm. The paper describes the system layout and the basics of the controls: from the alghorithms of the arm actuators to the vehicle on board telemetry and diagnostic. The paper reports the comparison between the IFC system (implemented on the vehicle) and a more traditional approach based on a Load Sense Flow Sharing concept. The benefits of the IFC solution are highlighted focusing on the energy efficiency (very important especially in the case of CNG engines, where the torque available at idle is significantly lower than diesel engines), but also in terms of controlability and response (due to the lack of load sensing signal lines).