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Energy and environmental contexts of cities, transportation systems, and emerging vehicle technologies : how plug-in electric vehicles and urban design influence energy consumption and emissionsNichols, Brice G. 19 March 2014 (has links)
This thesis is divided into two parts. The first evaluates the role of the built environment in life-cycle energy consumption, by comparing different neighborhood and city styles. Through a holistic modeling and accounting framework, this work identifies the largest energy-consuming sectors, among residential and commercial buildings, personal vehicles and transit trips, and supporting infrastructure (roads, sidewalks, parking lots, water pipes, street lighting). Life-cycle energy calculations include operational energy use (e.g., gasoline for vehicles, electricity and natural gas for buildings) and embodied energy used to produce materials and construct buildings and infrastructure. Case study neighborhoods in Austin, Texas, and larger-scale regional models suggest that building energy demands comprise around 50% of life-cycle energy demands, while transportation demands (from driving and infrastructure alike) contribute around 40%, across all cases. However, results also suggest that population density and average residential unit size play a major role in defining per-capita energy consumption. Operational demands made up about 90% of life-cycle energy demands, suggesting that v most urban energy savings can be obtained from reduced personal vehicle trips and more efficient vehicles and buildings. Case study comparisons suggest that neighborhoods and regions with greater density and higher share of multi-family housing units tend to reduce operational (and thus life-cycle) energy demands with less travel demand and decreased home and work energy use, per capita. The second part of this modeled plug-in electric vehicle (PEV) emissions impacts in Texas, by considering four possible vehicle adoption scenarios (where PEVs make up 1, 5, 10, and 25% of total passenger vehicles). The analysis anticipates PEV electricity demand and emissions rates, based on current Texas power grid data. Results indicate that PEV emissions depend significantly on which specific power plants are used to power the vehicles, but that PEVs' average per-mile emissions rates for NO[subscript x], PM, and CO₂ are all likely to be lower than today's average passenger car, when today's average mix is used. Power produced from 100% coal plants could produce 14 times as much NO[subscript x], 3,200 times as much SO₂, nearly 10 times as much CO₂ and CO₂eq, 2.5 times as much PM₁₀, and VOCs, and nearly 80 times the NO₂ compared to a grid with 100% natural gas plants. / text
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Sustainable green infrastructure and operations planning for plug-in hybrid vehicles (PHEVs) : a Tabu Search approachDashora, Yogesh 27 January 2011 (has links)
Increasing debates over a gasoline independent future and the reduction of greenhouse gas (GHG) emissions has led to a surge in plug-in hybrid electric vehicles (PHEVs) being developed around the world. Due to the limited all-electric range of PHEVs, a daytime PHEV charging infrastructure will be required for most PHEVs’ daily usage. This dissertation, for the first time, presents a mixed integer mathematical programming model to solve the PHEV charging infrastructure planning (PCIP) problem. Our case study, based on the Oak Ridge National Laboratory (ORNL) campus, produced encouraging results, indicates the viability of the modeling approach and substantiates the importance of considering both employee convenience and appropriate grid connections in the PCIP problem. Unfortunately, the classical optimization methods do not scale up well to larger practical problems. In order to effectively and efficiently attack larger PCIP problems, we develop a new MASTS based TS algorithm, PCIP-TS to solve the PCIP. The results from computational experiments for the ORNL campus problem establish the dominant supremacy of the PCIP-TS method both in terms of solution quality and computational time. Additional experiments with simulated data representative of a problem that might be faced by a small city show that PCIP-TS outperforms CPLEX based optimization.
Once the charging infrastructure is in place, the immediate problem is to judiciously manage this system on a daily basis. This thesis formally develops a mixed integer linear program to solve the daily the energy management problem (DEM) faced by an organization and presented results of a case study performed for ORNL campus. The results from our case study, based on the Oak Ridge National Laboratory (ORNL) campus, are encouraging and substantiate the importance of controlled PHEV fleet charging and realizing V2G capabilities as opposed to uncontrolled charging methods. Although optimal solutions are obtained, the solver requires practically unacceptable computational times for larger problems. Hence, we develop a new MASTS based TS algorithm, DEM-TS, for the DEM models. Results for ORNL campus data set prove the dominant computational efficiency of the DEM-TS. For the simulated extended sized problems that resemble the complexity of a problem faced by a small city, the results prove that DEM-T not only achieves optimality, but also produces sets of multiple alternate optimal solutions. These could be very helpful in practical settings when alternate solutions are necessary because some solutions may not be deployable due to unforeseen circumstances. / text
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Intelligent Infrastructures for Charging Reservation and Trip Planning of Connected Autonomous Electric VehiclesShaikh, Palwasha Waheed 24 September 2021 (has links)
For an environmentally sustainable future, electric vehicle (EV) adoption rates have been growing exponentially around the world. There is a pressing need for constructing smart charging infrastructures that can successfully integrate the large influx of connected and autonomous EVs (CAEVs) into the smart grids. To fulfill the aspiration of massive deployment of autonomous mobility on demand (AMoD) services, the proposed fast and secure framework will need to address the long charging times and long waiting times of static charging. It will also need to consider dynamic wireless charging as a viable solution for the CAEVs on the move. In this thesis, a novel three-layer charging system design of static and dynamic wireless charging that can operate with the existing wired charging infrastructure and standards for Intelligent Transportation System (ITS) is presented. This internet of things (IoT) application is accompanied by a proposed handshake protocol with light-weight request message frames. It employs vehicle to infrastructure (V2I) and vehicle to grid (V2G) communications for fulfilling charging requests of CAEVs with the shortest possible route to the destination. The charging requests of the CAEV users are fulfilled by dynamically distributing the request over the three different types of charging equipment. Further, the requests are serviced and billed privately and securely using two different proposed payment schemes with the encrypted virtual currency. The hardware independent system can detect misalignment of the CAEVs on the wireless charging pads and the speed issue errors in dynamic wireless charging systems as well as avoid free-riders. Additionally, the proposed dynamic wireless charging network (DWCN) design specification tool is analyzed. The suggestions made by the tool for building a DWCN can enable implementers to achieve the desired charging delivery performance at the lowest cost possible. Finally, the presented system is simulated, and this verified and validated simulator is revealed to make reservations and plan trips with minimum waiting times, travel costs, and battery consumption per vehicle trip. The system results proved 90.25% charge delivery efficiency. This system is then compared with alternative system designs to help showcase its ability to aid implementers and analysts in making design choices with the simulation.
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Are multi-car households better suited for battery electric vehicles? – Driving patterns and economics in Sweden and GermanyJakobsson, Niklas, Gnann, Till, Plötz, Patrick, Sprei, Frances, Karlsson, Sten 21 December 2020 (has links)
Battery electric vehicles (BEVs) could reduce CO2 emissions from the transport sector but their limited electric driving range diminishes their utility to users. The effect of the limited driving range can be reduced in multi-car households where users could choose between a BEV and a conventional car for long-distance travel. However, to what extent the driving patterns of different cars in a multi-car household’s suit the characteristics of a BEV needs further analysis. In this paper we analyse the probability of daily driving above a fixed threshold for conventional cars in current Swedish and German car driving data. We find second cars in multi-car households to require less adaptation and to be better suited for BEV adoption compared to first cars in multi-car households as well as to cars in single-car households. Specifically, the share of second cars that could fulfil all their driving is 20 percentage points higher compared to first cars and cars from single-car households. This result is stable against variation of driving range and of the tolerated number of days requiring adaptation. Furthermore, the range needed to cover all driving needs for about 70% of the vehicles is only 220 km for second cars compared to 390 km for the average car. We can further confirm that second cars have higher market viability from a total cost of ownership perspective. Here, the second cars achieve a 10 percentage points higher market share compared to first cars, and to cars in single-car households for Swedish economic conditions, while for Germany the corresponding figure is 2 percentage points. Our results are important for understanding the market viability of current and near-future BEVs.
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Investigation of a Novel Vapor Chamber for Efficient Heat Spreading and Removal for Power Electronics in Electric VehiclesPatel, Anand Kishorbhai 05 1900 (has links)
This work investigated a novel vapor chamber for efficient heat spreading and heat removal. A vapor chamber acting as a heat spreader enables for more uniform temperature distribution along the surface of the device being cooled. First, a vapor chamber was studied and compared with the traditional copper heat spreader. The thickness of vapor chamber was kept 1.35 mm which was considered to be ultra-thin vapor chamber. Then, a new geometrical model having graphite foam in vapor space was proposed where the graphite foam material was incorporated in vapor space as square cubes. The effects of incorporating graphite foam in vapor space were compared to the vapor chamber without the embedded graphite foam to investigate the heat transfer performance improvements of vapor chamber by the high thermal conductivity graphite foam. Finally, the effects of various vapor chamber thicknesses were studied through numerical simulations. It was found that thinner vapor chamber (1.35 mm thickness) had better heat transfer performance than thicker vapor chamber (5 mm thickness) because of the extreme high effective thermal conductivities of ultra-thin vapor chamber. Furthermore, the effect of graphite foam on thermal performance improvement was very minor for ultra-thin vapor chamber, but significant for thick vapor chamber. The GF could help reduce the junction temperature by 15-30% in the 5-mm thick vapor chamber. Use of GF embedded vapor chamber could achieve 250-400 Watt per Centimeter square local heat removal for power electronics. The application of this is not only limited to electronic devices but actuator and avionics cooling in aircrafts, thermal management of electronics in directed energy weapon systems, battery thermal management for electric and hybrid vehicles, smart phones cooling, thus covering a wide gamut of heat flux applications.
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A Hybrid Energy Storage System Using Series-Parallel Reconfiguration TechniqueTu, Chia-Hao January 2016 (has links)
Technology advancements enable and encourage higher system electrifications in various applications. More electrified applications need more capable and higher performing sources of energy in terms of power delivery, power regeneration, and energy capacity. For example, in electric, hybrid electric, and plug-in hybrid electric vehicle applications (EVs, HEVs, and PHEVs), the power and energy ratings of the vehicle energy storage system (ESS) have a direct impact on the vehicle performance. Many researchers investigated and studied various aspects of hybrid energy storage systems (HESS) wherein multiple ESSs are combined together to share system loads, increase ESS capabilities, and cycle life. Various configurations and their application specific topologies were also proposed by other researchers; the potential of HESS has been proven to be very promising.
In this research, the goal is to present the theory of a HESS configuration that
has not been discovered thus far. This HESS configuration is called a series-parallel
reconfigurable HESS (SPR-HESS) since it is capable of recombining multiple storage
systems into different series, parallel, or series-parallel configurations, via power electronic converters, to accommodate different operation modes and load requirements. Simulations, as well as experimental verifications, are presented in this thesis. / Thesis / Doctor of Philosophy (PhD)
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The different perceptions toward hybrid vehicles between United States and ChinaChun-Hsiung, Jim Chang 01 January 2007 (has links)
The purpose of this study was to determine Chinese and U.S. consumers' attitudes and perceptions toward hybrid cars and the likelihood of purchasing one in the future.
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Electric Vehicles and the Utility Distribution Grid: An Impact StudyMatthew Brian Campbell (18086248) 01 March 2024 (has links)
<p dir="ltr"><b><i>Background</i></b><b>:</b> The increase in EV deployment is presenting numerous energy challenges to the utility distribution infrastructure. The energy demands created by EV charging sessions and the growing call to develop a network of DCFC charging facilities increases operational risk to the utilities in the ability to provide safe and reliable electricity to all customers.</p><p dir="ltr"><b><i>Purpose:</i></b> The purpose of this study is to identify the extent of impact to the utility distribution grid from an increasing EV (electric vehicle) adoption.</p><p dir="ltr"><b><i>Setting</i></b><b>: </b>In total, there were 3,020 rows of distribution circuit feeder data collected from the PG&E DIDF and National Grid NY System Reporting Tool between 2022 – 2023. Additionally, 48 documents, engineering reports, rate filings, articles, research studies, and utility whitepapers were examined.</p><p dir="ltr"><b><i>Research Design:</i></b> Impact analysis using a mixed methodology.</p><p dir="ltr"><b><i>Data Collection and Analysis:</i></b> A single research question was used to formulate an impact analysis to the utility distribution infrastructure under a mixed methodology. A quantitative analysis to determine circuit burden based on historical feeder capacity data and conduct hypothetical impact testing based on a set of ten variables. A qualitative analysis was administered to support these results and further design recommendations for the utility system under a logic model.</p><p dir="ltr"><b><i>Findings:</i></b> The PG&E and Utility National Grid EV and Circuit Impact Analysis demonstrated high susceptibility to overburden under a moderate number of level 2 EV chargers and significantly more when the loading impact was the result of DCFC facilities. The additional exploratory research yielded a consistent theme of mitigation strategies applicable to all electric utilities.</p><p><br></p><p dir="ltr"><b><i>Conclusions</i></b><i>:</i> Portions of the electric distribution infrastructure, operated by hundreds of utilities across the United States must be analyzed, upgraded, and adequately managed under systematic programs which promote facility upgrades, energy management, technology integration, such as AMI. Further, the execution of regulatory strategies for smart policy development and investment into hosting capacity tools are critical to reducing EV impact to the utility.</p><p dir="ltr"><b><i>Keywords</i></b><i>: </i>EV, electric utility, EV grid impacts, EV grid analysis, EV managed charging, EV AMI infrastructure.</p>
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Metodologia de dimensionamento do sistema de tração para veículos elétricos. / Methodology of propulsion system design of electric vehicles.Tanaka, Carlos Naomi 10 December 2012 (has links)
O interesse por veículos elétricos voltou a crescer nos últimos anos, principalmente, devido às questões ambientais e de eficiência energética. Aliado ao desenvolvimento de fontes e acumuladores de energia com densidades de energia e potência maiores que viabilizam a utilização de veículos elétricos em substituição parcial dos veículos com motores a combustão interna, já surgem comercialmente no mercado alguns modelos de veículos elétricos. Neste contexto, também cresce a necessidade de recursos humanos capacitados e ferramentas auxiliares para o dimensionamento dos componentes dessa nova geração de veículos automotores. Este trabalho apresenta uma metodologia simples e direta de dimensionamento do sistema de tração para veículos elétricos autônomos, bem como os resultados de uma aplicação prática da utilização desta metodologia no desenvolvimento de veículos elétricos fora de estrada para transporte de pessoas e de material. A comparação entre os resultados práticos obtidos com os cálculos realizados mostra que a metodologia, com o equacionamento completo e abrangente apresentado, fornece resultados com excelente exatidão. / The interest in electric vehicles is growing again in recent years, mainly due to environmental concerns and energy efficiency issues. Combined with the development of energy storage devices with higher power and energy densities that enable the use of electric vehicles, some models already appear commercially in the market replacing vehicles with internal combustion engines in specific applications. In this context, it also increases the need for trained human resources and auxiliary tools for designing the components of this new vehicles generation. This dissertation presents a simple and direct methodology of propulsion system design for autonomous electric vehicles as well as the results of a practical application of using this methodology in the development of off-road electric vehicles for people and material transport. The comparison between the practical results obtained with the calculations shows that the methodology, with the complete and comprehensive equations presented, provides results with excellent accuracy.
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Metodologia de dimensionamento do sistema de tração para veículos elétricos. / Methodology of propulsion system design of electric vehicles.Carlos Naomi Tanaka 10 December 2012 (has links)
O interesse por veículos elétricos voltou a crescer nos últimos anos, principalmente, devido às questões ambientais e de eficiência energética. Aliado ao desenvolvimento de fontes e acumuladores de energia com densidades de energia e potência maiores que viabilizam a utilização de veículos elétricos em substituição parcial dos veículos com motores a combustão interna, já surgem comercialmente no mercado alguns modelos de veículos elétricos. Neste contexto, também cresce a necessidade de recursos humanos capacitados e ferramentas auxiliares para o dimensionamento dos componentes dessa nova geração de veículos automotores. Este trabalho apresenta uma metodologia simples e direta de dimensionamento do sistema de tração para veículos elétricos autônomos, bem como os resultados de uma aplicação prática da utilização desta metodologia no desenvolvimento de veículos elétricos fora de estrada para transporte de pessoas e de material. A comparação entre os resultados práticos obtidos com os cálculos realizados mostra que a metodologia, com o equacionamento completo e abrangente apresentado, fornece resultados com excelente exatidão. / The interest in electric vehicles is growing again in recent years, mainly due to environmental concerns and energy efficiency issues. Combined with the development of energy storage devices with higher power and energy densities that enable the use of electric vehicles, some models already appear commercially in the market replacing vehicles with internal combustion engines in specific applications. In this context, it also increases the need for trained human resources and auxiliary tools for designing the components of this new vehicles generation. This dissertation presents a simple and direct methodology of propulsion system design for autonomous electric vehicles as well as the results of a practical application of using this methodology in the development of off-road electric vehicles for people and material transport. The comparison between the practical results obtained with the calculations shows that the methodology, with the complete and comprehensive equations presented, provides results with excellent accuracy.
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