Дисертації з теми "Vehicle fleet emissions"
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Giacosa, Matteo. "Carbon dioxide abatement options for heavy-duty vehicles and future vehicle fleet scenarios for Finland, Sweden and Norway." Thesis, KTH, Energisystemanalys, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-226144.
Повний текст джерелаBassène, Stéphane (Stéphane Alfred) 1977. "Potential for reducing fuel consumption and greenhouse gas emissions from the U.S. light-duty vehicle fleet." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/16794.
Повний текст джерелаIncludes bibliographical references (leaves 66-68).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Greenhouse gases, such as carbon dioxide, trap solar heat in the atmosphere, raising its temperature. While comprising only about 5% of global population, the U.S. is responsible for nearly one fourth of global annual CO2 emissions. Transportation accounts for a third of all carbon dioxide emissions in the country, and about one fourth worldwide. U.S. passenger cars and light trucks accounting for nearly two thirds of the net carbon equivalent emissions from transportation, any successful national strategy to reduce greenhouse gas emissions would need to address transportation sector emissions. Building upon a vehicle technology assessment conducted at MIT ("On the Road in 2020", Weiss et al., 2000), this study assesses the potential for reducing the U.S. light duty vehicle fleet fuel consumption and energy use. The vehicles technologies considered are an evolving gasoline-fueled baseline vehicle with steadily decreasing fuel consumption, and a gasoline internal combustion engine hybrid vehicle with an advanced body design. Using a vehicle fleet turnover model, the impact on the light-duty fleet of various technology penetration scenarios is assessed. The effects of other factors including the light-duty vehicle stock growth, the increasing per-vehicle annual distance traveled and the sales share of light-duty trucks are evaluated as well. The reduction of new vehicle fuel consumption achieved on the evolving baseline and advanced ICE-Hybrids vehicles provides the most significant savings in fleet energy use over all the other considered measures. Actions aiming at reducing the stock and the total distance traveled growth rate appear to have significant effects on fleet fuel consumption as well, while an increasing share of light-duty trucks will have only a modest impact. Finally, various policy options are discussed. Actions will need to be taken by the Federal Government and the other stakeholders if significant petroleum and greenhouse gas emissions reductions are to be achieved.
by Stéphane Bassène.
S.M.
Khusid, Michael. "Potential of electric propulsion systems to reduce petroleum use and greenhouse gas emissions in the U.S. light-duty vehicle fleet." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62769.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 74-78).
In the summer of 2008, the United States of America experienced an oil shock, first of a kind since 1970s. The American public became sensitized to the concerns about foreign oil supply and climate change and global warming, and to the role of transportation in emissions of carbon dioxide and other greenhouse gases (GHG). Several proposed federal policies impose stringent limits on the transportation sector, in terms of fuel consumption and GHG emissions. Within transportation sector, light duty vehicles (LDVs) - cars, light trucks and SUVs - currently emit the most GHGs. Hybrid technology emerged as a promising option to address several of these challenges. A modern hybrid electric vehicle (HEV) offers significantly better fuel economy together with lower levels of pollutant and CO2 emissions. HEVs are currently categorized as Advanced Technology Partial Zero Emission Vehicles (AT-PZEV) by California Air Resource Board. Recently, a new generation of vehicles, plug-in hybrid electric vehicles (PHEV), has been announced in the immediate future by major auto manufacturers. While HEVs have a relatively small battery that is recharged by the engine or by regenerative braking, a larger battery of a PHEV and a charger allows a vehicle owner to recharge the battery from the electric grid. The plug-in technology further increases fuel economy and reduces emissions from the tailpipe. For example, a Chevrolet Volt PHEV is expected to be launched as 2011 model with 40 mile allelectric travel with no tailpipe emissions. However, there are multiple challenges associated with the new technology. HEVs and PHEVs incur higher costs due to additional components, such as electric motors and motor controllers, and a battery. Today's batteries provide energy storage density hundred times lower than that of gasoline. Electricity consumed by hybrids is generated by coal and other fossil fuel power plants that emit harmful chemicals and greenhouse gases. The infrastructure for electric cars is at the infancy stage. Some government policies designed to introduce all-electric cars, such as the California ZEV mandate of the late 1990s, failed to introduce a sustained number of electric vehicles to the market. To provide an integrated approach to the causes and effects of electrified powertrains, two plausible scenarios of advanced vehicle market penetration were developed. Federal policies and consumer preferences were considered as primary drivers. Biofuels were considered alongside fossil fuels as primary energy sources for transportation. Rapid adoption of PHEVs was found to cause a perceptible, but not a significant increase in electric power demand. The scenarios demonstrated ability to achieve fuel economy milestones and quantified the challenge of achieving 80% reduction in greenhouse gas emissions by 2050.
by Michael Khusid.
S.M.in Engineering and Management
Wagner, Christopher. "Regression Model to Project and Mitigate Vehicular Emissions in Cochabamba, Bolivia." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1501719312999566.
Повний текст джерелаSamoylov, Alexander V. "Improvement of the efficiency of vehicle inspection and maintenance programs through incorporation of vehicle remote sensing data and vehicle characteristics." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50410.
Повний текст джерелаKeogh, Diane Underwood. "Development of a particle number and particle mass emissions inventory for an urban fleet : a study in South-East Queensland." Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/30297/1/Diane_Keogh_Thesis.pdf.
Повний текст джерелаKeogh, Diane Underwood. "Development of a particle number and particle mass emissions inventory for an urban fleet : a study in South-East Queensland." Queensland University of Technology, 2009. http://eprints.qut.edu.au/30297/.
Повний текст джерелаCestau, Cubero Silvia. "Sostenibilidad técnica, económica y ambiental de flotas comerciales de vehículos eléctricos." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/286233.
Повний текст джерелаEsta tesis analiza si el vehículo eléctrico es sostenible técnica, económica y ambientalmente y puede sustituir a un vehículo de combustión interna, estudiando la flota de vehículos eléctricos de una empresa que tiene un servicio de carsharing contratado para el desplazamiento de sus comerciales. Para ello, se han examinado los trayectos de ocho vehículos eléctricos en seis ciudades españolas a través de los datos obtenidos de su CAN bus mediante el UCV (equipo embarcado) durante los años 2012 y 2013. Además, se han realizado medidas de la carga de la batería, para conocer su comportamiento (autonomía, autodescarga y envejecimiento) y sus consumos energéticos. El objetivo es estudiar su ciclo de vida, valorando su eficiencia y efectos ambientales (emisiones de CO2 y ruido), y concluir cuantificando su impacto económico (combustibles y coste total de la propiedad) y otras posibles ventajas asociadas al vehículo eléctrico (responsabilidad social corporativa, exención de impuestos, etc).
Isak, Eklöv. "Energieffektivisering inom transportsektorn : En fallstudie på ett företagsfordonspark." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-435080.
Повний текст джерелаWhitehead, Jake. "Making the Transition to a ‘Green’ Vehicle Fleet : An analysis of the choice and usage effects of incentivising the adoption of low-emission vehicles." Licentiate thesis, KTH, Transport- och lokaliseringsanalys, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-131296.
Повний текст джерелаÖvergången till en ”grön” fordonsflotta är en betydelsefull strävan för samtliga beslutsfattare. När de globala utsläppen av växthusgaser ständigt ökar råder det ingen tvekan om att samtliga åtgärder som kan bidra till en hållbar utveckling bör implementeras. Vid utformandet av sådana åtgärder är det dock viktigt ordentliga kostnads-nyttoanalyser utförs, så att hänsyn tas till potentiellt negativa "rebound" och förestålse fås för vilka individer som påverkas. I två artiklar analyserar denna avhandling effekterna på val och användning av ett undantag för fordon med låga utsläpp (LEV) från Stockholms trängselskatt system. Ambitionen med denna studie har varit att förstå: i vilken utsträckning detta undantag i politik påverkade efterfrågan på LEVs, vilka personer som den riktade sig till, om politiken lett till några "rebound" effekter (ökad LEV användning), och slutligen vad effekten var i termer av utsläpp. Artikel I använder en MNL modell för att undersöka demografin av de personer som köpt en LEV i Stockholm under 2008 samt i vilken utsträckning undantaget påverkade denna efterfrågan. Det konstaterades att de ägare som bor inom avspärrningen men som pendlade över gränsen hade den högsta benägenheten att köpa en undantagen LEV. Undantagen från tränselskatt visade sig ha haft en väsentlig inverkan på efterfrågan på undantagna LEVs, andelen av dessa fordon ökade med 1,9% till 18,9% totalt eller ytterligare 550 LEV inköp under 2008. I artikel II beräknas skillnaderna i årlig användning mellan LEV och konventionella fordon med demografiskt liknande ägare genom "propensity score matching" i syfte att kontrollera för potentiell självselektion. Genom detta förfarande fanns de direkta utsläppen från fordonsägare som övergått till en LEV ha minskat med 52,4%. Även om undantaget från tränselskatt var delvis ansvarigt för att öka antalet LEVs verkar det också ha uppmuntrat en ökad årlig användning, vilket ledde till "rebound" effekter som motverkade den potentiella utsläppsminskningen (ökning i LEV användning för ägare som åkte över gränsen var 12,2% för dem som levde inom och 8,5 % för dem som bodde utanför). I denna avhandling har effekterna av en incitament baserad politik i Stockholm på både efterfrågan och användning av LEVs lyfts fram. Fördelarna liksom de möjliga komplikationerna av detta initiativ har också diskuterats i hopp om att upplysa beslutsfattare så att de potentiella utsläppsminskningarna från liknande politiska initiativ i framtiden kan maximeras. Personliga fordon kommer sannolikt fortsatt dominera andelen hem-arbete resor under de kommande åren och det är därför nödvändigt att städerna fortsäter sina ansträngningar förberömvärd att uppmuntra övergången till en "grön" fordonsflotta. Det är dock viktigt att dessa ansträngningar leder till incitament baserad politik som är balanserad, rimlig och utformade för att minimera de potentiellt betydande "rebound" effekter.
QC 20131025
Fomunung, Ignatius Wobyeba. "Predicting emissions rates for the Atlanta on-road light-duty vehicular fleet as a function of operating modes, control technologies, and engine charateristics." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/20834.
Повний текст джерелаRamírez, Roa Leonardo Andrés. "Contribution to the Assessment of the Potential of Low Viscosity Engine Oils to Reduce ICE Fuel Consumption and CO2 Emissions." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/73068.
Повний текст джерела[ES] Actualmente la industria de la automoción vive uno de los periodos de cambio más vertiginosos de las últimas décadas, marcado por un creciente interés en reducir los impactos medioambientales negativos generados por el consumo de combustibles fósiles y sus consecuentes emisiones nocivas de dioxido de carbono (CO2) generados durante el funcionamiento del motor de combustión interna alternativo (MCIA). Teniendo en cuenta que el proceso de sustitución de la flota actual por una totalmente independiente de los combustibles fósiles puede tomar varias décadas, y ante la urgencia inmediata de reducir las emisiones de CO2, se puede decir que actualmente es más urgente hacer una optimización de los vehículos con motorizaciones convencionales. Entre las soluciones técnicas que se han desarrollado para mejorar la eficiencia del MCIA destaca la utilización de aceites de baja viscosidad como un método efectivo y de bajo coste de implementación que brinda reducciones del consumo entre el 0.5% y el 5%. Durante el desarrollo de esta tesis se ha llevado a cabo un plan de ensayos enfocado en determinar valores concretos de ahorro de combustible esperados cuando se utilizan aceites de baja viscosidad en vehículos de trabajo ligero y pesado. El plan de estudios se dividió en tres partes; la primera se centró en el estudio de MCIA de vehículos de trabajo ligero, utilizando un motor Diesel representativo del mercado Europeo y llevando a cabo pruebas comparativas en arrastre, puntos de funcionamiento estacionarios y ciclos transitorios de homologación. La segunda parte del estudio consta de otro ensayo comparativo, esta vez utilizando una flota de vehículos de trabajo pesado. El estudio se realizó con la flota de autobuses urbanos de la ciudad de Valencia, incluyéndose 3 modelos de autobuses, con 2 tipos de motorización diferente. La tercera parte del estudio se centró en el comportamiento del coeficiente de friction en los pares tribológicos del motor haciendo ensayos comparativos con tribómetros especializados; uno de movimiento alternativo para simular las condiciones de la interfaz piston-camisa y un "bola y disco" para simular la lubricación en el sistema de distribución, específicamente en la interfaz leva-taqué. Los diversos estudios comparativos han servido para analizar como es la respuesta general de la fricción y el consumo de combustible cuando se usan aceites de baja viscosidad, tanto a nivel de motor como para la totalidad del vehículo, encontrando diferencias de par en los ensayos de arrastre, de consumo específico de combustible en los ensayos de motor en estado estacionario y diferencias totales de consumo de combustible en los ensayos en régimen transitorio y en flota, que a su vez han permitido estimar la reducción esperada en la huella de carbono.
[CAT] Actualment la indústria de l'automoció viu un dels períodes de canvi més vertiginoses de les últimes dècades, marcat per un creixent interès en reduir els impactes mediambientals negatius generats pel consum de combustibles fòssils i els seus conseqüents emissions nocives de diòxid de carboni (CO2) generats durant el funcionament del motor de combustió interna alternatiu (MCIA). Tenint en compte que el procés de substitució de la flota actual per una totalment independent dels combustibles fòssils pot prendre diverses dècades, i davant la urgència immediata de reduir les emissions de CO2, es pot dir que actualment és més urgent fer una optimització dels vehicles amb motoritzacions convencionals. Entre les solucions tècniques que s'han desenvolupat per millorar l'eficiència del MCIA destaca la utilització d'olis de baixa viscositat com un mètode efectiu i de baix cost d'implementació que brinda reduccions del consum entre el 0.5% i el 5%. Durant el desenvolupament d'aquesta tesi s'ha dut a terme un pla d'assajos enfocat a determinar valors concrets d'estalvi de combustible esperats quan s'utilitzen olis de baixa viscositat en vehicles de treball lleuger i pesat. El pla d'estudis es va dividir en tres parts; la primera es va centrar en l'estudi de MCIA de vehicles de treball lleuger, utilitzant un motor dièsel representatiu del mercat Europeu i portant a terme proves comparatives en arrossegament, punts de funcionament estacionaris i cicles transitoris d'homologació. la segona part de l'estudi consta d'un altre assaig comparatiu, aquest cop utilitzant una flota de vehicles de treball pesat. L'estudi es va realitzar amb la flota d'autobusos urbans de la ciutat de València, incloent-se 3 models d'autobusos, amb 2 tipus de motorització diferent. La tercera part de l'estudi es va centrar en el comportament del coeficient de friction en els parells tribològics del motor fent assajos comparatius amb tribómetros especialitzats; Un acció reciprocante per simular les condicions del piston camisa i un bola i disc per simular la lubricació en el sistema de distribució. Els diversos estudis comparatius han servit per analitzar com és la resposta general de la fricció i el consum de combustible quan es fan servir olis de baixa viscositat, tant a nivell de motor com la totalitat del vehicle, trobant diferències de bat a els assajos d'arrossegament, de consum específic de combustible en els assajos de motor en estat estacionari i diferències totals de consum de combustible en els assajos en règim transitori i en flota, que al seu torn han permès calcular la reducció en la petjada de carbono.
Ramírez Roa, LA. (2016). Contribution to the Assessment of the Potential of Low Viscosity Engine Oils to Reduce ICE Fuel Consumption and CO2 Emissions [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/73068
TESIS
Bruni, Antonio de Castro. "Critérios para identificação de veículos leves do ciclo Otto com elevadas emissões, utilizando dispositivo de sensoriamento remoto." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/6/6134/tde-19042018-120404/.
Повний текст джерелаApproximately 600,000 deaths occur worldwide annually for children up to five years of age. Pneumonia is the leading cause and more than 50 per cent of these deaths are attributed to air pollution. It is still responsible for increased risk of respiratory infections, asthma, adverse neonatal conditions and congenital anomalies. Air pollution also affects the cognitive development of children and induces future development of chronic diseases in adulthood. In order to define criteria based on remote sensing measurements to identify Otto cycle light duty vehicles (LDV) with high emissions of carbon monoxide, hydrocarbons or nitric oxide it was used secondary data produced by Remote Sensing do Brasil Ltda, from which 179,142 inuse vehicles were selected, that belongs to the city of São Paulos current fleet. All those vehicles had complete measurements of emission of carbon monoxide (CO), hydrocarbons (HC) and nitric oxide (NO), and also speed and acceleration of the vehicle during measurements, and slope of the track at the place chosen for the measurements. Statistical models of the Generalized Additive Models for Location, Scale and Shape (GAMLSS) class were adjusted to test the influence of fuel type, Vehicle Specific Power (VSP) and of the Brazilian Vehicle Emission Control Program [Proconve] phases on CO, HC and NO emissions, measured using Remote Sensing Device (RSD). The emissions were then conceptually subdivided into two groups: vehicles with normal and abnormal emission, for the various pollutants in vehicles of L3, L4 and L5 phases of Proconve, which were of interest for the air quality management. Latent variables were defined to indicate the distribution of vehicles in relation to those groups and phases. The algorithm Expectation Maximization (EM) was employed to identify all parameters of the distributions. We use the 98 per cent percentiles of the statistical distribution set, for vehicles of groups with normal emissions to determine the limit values for vehicles with high emissions of pollutants and Proconve Phase. Therefore, the Type I Error was set at 2 per cent and this percentage was established considering the Type II Error to point the vehicle as having normal emission when in fact it is a high emitter. Through this approach, the indicative values of vehicles with high emissions according to the pollutant and the Proconve Phase were determined. Results of emissions measured with the RSD technique indicated a decrease in CO and HC emissions according to the Proconve Phase. For the NO, the emissions behavior did not follow the reductions imposed by the Proconve Phases. It was found that newer vehicles year model from 2005 to 2009 exclusively gasohol-powered vehicles, were the ones that presented the highest NO emissions. Several possible causative factors of this differential behavior of NO were discussed in this study. A significant increase in the environmental concentrations of Nitrogen Oxides (NOx) was detected in 2007, when this parameter was monitored in the winter period. This may indicate the influence of the high emitter vehicles, but it requires a more in-depth cause-effect study for confirmation of this behavior.
"Projection of PM2.5, BC, NOx and VOCs from the Future Vehicle Fleet: Impact of Alternative Vehicle Penetration Versus Continual Reductions in Emissions from Traditional Vehicles." Master's thesis, 2020. http://hdl.handle.net/2286/R.I.56959.
Повний текст джерелаDissertation/Thesis
Masters Thesis Civil, Environmental and Sustainable Engineering 2020
Musti, Sashank. "Evolution of the household vehicle fleet : anticipating fleet compostion, plug-in hybrid electric vehicle (PHEV) adoption and greenhouse gas (GHG) emissions in Austin, Texas." Thesis, 2009. http://hdl.handle.net/2152/ETD-UT-2009-12-681.
Повний текст джерелаtext
Paul, Binny Mathew. "Anticipating the impacts of climate policies on the U.S. light-duty-vehicle fleet, greenhouse gas emissions, and household welfare." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-05-3630.
Повний текст джерелаtext
Maduro, Miguelangel. "Well-to-wheel greenhouse gas emissions and energy use analysis of hypothetical fleet of electrified vehicles in Canada and the U.S." Thesis, 2010. http://hdl.handle.net/10155/141.
Повний текст джерелаUOIT
Min-YouTsai and 蔡旻侑. "A Heuristic Algorithm for Heterogeneous Fleet Feeder Vehicle Routing Problem Considering Carbon Emission." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/7x2zav.
Повний текст джерела國立成功大學
工業與資訊管理學系
107
With the booming of e-commerce, the demand for delivery has gradually increased. Delivery operators want to enhance competitiveness and reduce transportation costs. Therefore, there is a new model called Feeder Vehicle Routing Problem (FVRP), which is the extension of VRP. It mainly uses the cooperation of trucks and motorcycles to carry out delivery service. When motorcycles are out of commodity, it can directly find trucks for reloading. This reloading method can reduce overall travel costs and speed up delivery efficiency. Besides, as air pollution problems become more severe, the restrictions on carbon emission become stricter, which is a challenge for delivery operators. Therefore, this thesis adds carbon emission and electric motorcycle considerations, and proposes a Heterogeneous Fleet Feeder Vehicle Routing Problem Considering Carbon Emission (EFVRP). Then formulate a mathematical model and proposes a simulated annealing (SA) method for solving EFVRP. The objective of EFVRP is to minimize the total cost consisting of travel cost, carbon penalty cost, and fixed vehicle cost. The problem was solved by the optimization software Gurobi and the SA method respectively. The results show that SA is outperforming than Gurobi. For sensitivity analysis, the carbon emission penalty cost of motorcycle and the travel cost of an electric motorcycle is not significant.
Garcia, Rita Pinheiro. "Dynamic Fleet-Based Life-Cycle Assessment: Addressing Environmental Consequences of the Introduction of Electric Vehicles in Portugal." Doctoral thesis, 2016. http://hdl.handle.net/10316/30192.
Повний текст джерелаElectric vehicles (EVs) have been promoted as an alternative to reduce greenhouse gas (GHG) emissions, fossil fuel dependence, and urban pollution caused by the transportation sector; however, a large scale adoption of EVs faces significant challenges. A number of studies have assessed the effects of EVs in the electricity system and the environmental impacts of different scenarios of evolution of the transportation sector. However, few studies integrating both electricity and fleet displacement effects have been performed. A dynamic fleet-based life-cycle perspective is thus necessary to understand the consequences and determine the extent to which the introduction of EVs in the fleet can actually reduce rather than simply shift environmental impacts of personal transport. This thesis presents a dynamic fleet-based life-cycle framework to assess the effects on environmental impacts of the introduction of EVs in a fleet. The framework combines fleet analysis and dynamic life-cycle modelling of vehicles to investigate the displacement of conventional vehicles over time, and consequential life-cycle assessment of electricity to assess the changes induced in the electricity system due to EV charging. The analysis focused on the case of introducing battery electric vehicles (BEVs) in the Portuguese light-duty fleet and focused on GHG emissions. A comprehensive life-cycle assessment of electricity generation and supply in Portugal was also performed to identify the main drivers of impacts, how impacts change over time, and how charging time influences BEV GHG emissions. Reducing fleet-wide GHG emissions by displacing internal combustion engine vehicles (ICEVs) by BEVs in Portugal depends mostly on the GHG intensity of the Portuguese electricity system, on the degree of reduction in fuel consumption of new ICEVs, and on the level of penetration of BEVs. In order to achieve significant reductions compared to an increasingly more efficient ICEV fleet, a high BEV market share and electricity GHG intensity similar or lower to the current mix (485 g CO2 eq kWh-1) need to be realized. The response of the electricity system to BEV demand, regarding the changes in electricity generation by the various sources and corresponding GHG emissions, may thus determine the benefits of BEVs over conventional technologies. Electricity GHG emissions in Portugal vary significantly between years and throughout the year. As a result of the temporal variability in electricity generation and, in particular, in the marginal supply, the time of charging can have a major influence on the GHG benefits of ii BEVs. What has been considered, in general, the most favorable charging time from the economic and operation of the electricity system perspective (off-peak hours), may not be so from an environmental standpoint. In Portugal, simply encouraging charging during the night may increase emissions from the electricity system as a result of the fossil-based marginal electricity supply (mostly coal). Therefore, charging control strategies should ensure that surplus renewable energy use by BEVs is maximized so that environmental impacts can be reduced. However, interactions with other strategies to enable renewable energy sources, such as electricity storage, may be important and should be accounted for. When the electricity system includes significant storage of energy, for instance through pumped hydro storage (PHS), the effects of introducing BEVs go beyond the straightforward displacement of ICEVs and increase in electricity demand, to include significant indirect effects from the dynamics of storage. Such indirect effects may decrease or even offset the GHG benefits of ICEV displacement. However, the net effects on GHG emissions are very dependent on the technologies displaced both by PHS and by BEVs, so that detailed analysis is needed for any specific energy system, allowing for future technological improvements. The dynamic fleet-based life-cycle framework developed in this thesis provides a comprehensive environmental assessment of the adoption of a new technology, because it enables explicit assessment of changes in technologies and background systems over time in a fleet perspective, as well as indirect effects related to the existing system. In particular, this framework can be used to assess the effects on environmental impacts of other electricity-using products in a fleet perspective, and of measures that improve the energy efficiency of end-use applications or that shift the use of electricity. The change-oriented approach pursued can also aid in understanding the consequences of policies and strategies that enable and promote the use of electricity over other fuels.
Os veículos elétricos (EVs) têm sido apontados como alternativa para reduzir as emissões de gases com efeito de estufa (GEE), a dependência de combustíveis fósseis e a poluição em meio urbano causadas pelo sector dos transportes, mas a sua adoção enfrenta importantes desafios. Vários estudos avaliaram os efeitos dos EVs no sistema elétrico e os impactes ambientais de diferentes cenários de evolução do setor dos transportes, mas poucos analisaram em conjunto os efeitos ambientais sobre o sistema elétrico e aqueles relativos à substituição de veículos de combustão interna (VCIs). Deste modo, para perceber as consequências e determinar se a introdução de EVs na frota reduz efetivamente os impactes ambientais associados ao transporte individual ou se apenas os transferem para outras partes do sistema é necessário adotar uma perspetiva dinâmica de ciclo de vida (CV). Esta tese apresenta uma abordagem dinâmica de CV com base em modelos de frota para avaliar os efeitos ambientais da introdução de EVs numa frota. A abordagem combina análise de frotas e modelação dinâmica de CV de veículos com o objetivo de avaliar os efeitos da substituição de VCIs por EVs ao longo do tempo, e avaliação consequencial de CV de sistemas elétricos para avaliar as alterações induzidas no sistema elétrico devido ao carregamento dos EVs. A análise incidiu sobre a introdução de EVs a baterias (BEVs) no parque automóvel ligeiro português e focou-se na avaliação das emissões de GEE. Foi ainda realizada uma avaliação abrangente de CV da geração de eletricidade em Portugal com o objetivo de identificar os fatores que mais contribuem para os impactes, de que forma variam os impactes ao longo do tempo e qual a influência do horário de carregamento nas emissões de GEE dos BEVs. A redução total das emissões de GEE da frota automóvel em resultado da substituição de VCIs por BEVs em Portugal depende da intensidade de GEE do sistema elétrico português, do grau de redução no consumo de combustível dos novos VCIs e no nível de penetração de BEVs. De modo a alcançar reduções significativas em comparação com uma frota de VCIs cada vez mais eficientes, é necessário que a quota de mercado dos BEVs seja alta e que a intensidade de GEE do sistema elétrico seja inferior ou semelhante à atual (485 g CO2 eq kWh-1). A resposta do sistema elétrico à procura dos BEVs, relativamente à variação na geração de eletricidade pelas várias fontes e correspondente variação nas emissões de GEE, determina os benefícios dos BEVs relativamente aos VCIs. iv As emissões de GEE da eletricidade em Portugal variam significativamente de ano para ano e ao longo do ano. Devido à variabilidade temporal na geração de eletricidade e, em particular, na geração marginal, o horário de carregamento tem uma grande influência nas emissões de GEE causadas pelos BEVs. Aquele que tem sido considerado, em geral, o período mais favorável para o seu carregamento do ponto de vista da operação do sistema elétrico (horas de vazio), pode não o ser do ponto de vista da redução dos impactes ambientais. Em Portugal, incentivar o carregamento durante a noite pode resultar num aumento das emissões do sistema elétrico, uma vez que a tecnologia marginal é na maioria do tempo carvão. Deste modo, as estratégias de controlo dos carregamentos devem ser implementadas de forma a garantir a maximização da utilização da energia renovável em excesso para reduzir os impactes ambientais. No entanto, é preciso ter em conta a interação entre os BEVs e outras estratégias de utilização de energia renovável intermitente, como é o caso dos sistemas de armazenamento de eletricidade. Quando o sistema elétrico permite o armazenamento de quantidades significativas de eletricidade, por exemplo através de barragens hidroelétricas com sistemas de bombagem, os efeitos da introdução de BEVs vão além da simples substituição de VCIs e aumento da procura por eletricidade, para incluir efeitos indiretos significativos associados à dinâmica de armazenamento. Tais efeitos podem diminuir ou mesmo anular os benefícios em termos de emissões de GEE associados à substituição de VCIs. No entanto, o efeito líquido sobre as emissões de GEE depende muito das tecnologias substituídas tanto pelos BEVs como pelos sistemas de armazenamento, pelo que é necessário efetuar uma análise detalhada para cada sistema energético, tendo em conta melhorias tecnológicas futuras. A abordagem desenvolvida nesta tese permite avaliar de forma integrada os impactes ambientais causados pela adoção de uma nova tecnologia, uma vez que possibilita avaliar explicitamente alterações no sistema ao longo do tempo bem como efeitos indiretos. Em particular, a abordagem desenvolvida pode ser usada para avaliar os efeitos ambientais de outros produtos que consomem eletricidade numa perspetiva de frota, bem como de medidas para melhorar a eficiência energética. A abordagem consequencial implementada permite ainda ajudar a compreender as consequências de políticas e estratégias que promovam a utilização de eletricidade em substituição de outros combustíveis.
FCT - SFRH/BD/51299/2010
Kubis, Christian Alexander. "Upstream emissions for battery electric vehicles in the U.S. fleet regulation: environmental implications and carbon dioxide abatement potential." Master's thesis, 2017. http://hdl.handle.net/10362/22287.
Повний текст джерелаAlhajeri, Nawaf Salem. "Assessing the sustainability of transportation fuels : the air quality impacts of petroleum, bio and electrically powered vehicles." Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-05-934.
Повний текст джерелаtext