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A method for developing a Triple-Bottom-Line business case for the implementation of alternative fuels and technologyThiets, Robert Clyde 13 May 2008 (has links)
Alternative fuels and technologies for truckload carriers can provide significant environmental and social benefits over traditional heavy duty diesel vehicles by reducing petroleum-based fuel consumption and vehicle tailpipe emissions. These alternative fuels and technologies, however, often carry a cost premium or require significant capital investment. Dedicating vehicles, equipment, and infrastructure to an alternative fuel or technology also represents a significant risk in the extremely volatile trucking business. A Triple-Bottom-Line analysis, which includes economic, social, and environmental impacts of an alternative fuel or technology will strengthen the business case by incorporating the benefits of emissions reduction. A stronger business case will promote the use of alternative fuels and technologies while mitigating the risk.
This thesis proposes a method for identifying alternative fuels and technologies that provide the best Triple-Bottom-Line benefit and provides a structure for modeling the emissions of the target application, quantifies the value of emissions reduction, and constructs a Triple-Bottom-Line business case. The Triple-Bottom-Line business case proposed by this method is incremental. It presupposes an existing or planned truckload carrier business already exists and only investigates the changes which occur with implementation of an alternative fuel or technology. This method may be useful for any carrier business or any company with an extensive shipping and logistics network. A case study, which was created for large automotive manufacturer, details the Triple-Bottom-Line business case for an on-site compressed natural refueling system and vehicles.
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Applying alternative fuels in place of hydrogen to the jet ignition processToulson, E. January 2008 (has links)
Hydrogen Assisted Jet Ignition (HAJI) is an advanced ignition process that allows ignition of ultra-lean mixtures in an otherwise standard gasoline fuelled spark ignition engine. Under typical operating conditions, a small amount of H2 (~ 2 % ofthe main fuel energy or roughly the equivalent of 1 g/km of H2) is injected just before ignition in the region of the spark plug. By locating the spark plug in a small prechamber (less than 1 % of the clearance volume) and by employing a H2 rich mixture, the content of the prechamber is plentiful in the active species that form radicals H and OH on decomposition and has a relatively high energy level compared to the lean main chamber contents. Thus, the vigorous jets of chemically active combustion products that issue through orifices, which connect to the main chamber, burn the main charge rapidly and with almost no combustion variability (less than 2% coefficient of variation in IMEP even at λ = 2.5). / The benefits from the low temperature combustion at λ = 2 and leaner are that almost zero NOx is formed and there is an improvement in thermal efficiency. Efficiency improvements are a result of the elimination of dissociation, such as CO2 to CO, which normally occurs at high temperatures, together with reduced throttling losses to maintain the same road power. It is even possible to run the engine in an entirely unthrottled mode, but at λ = 5. / Although only a small amount of H2 is required for the HAJI process, it is difficult to both refuel H2 and store it onboard. In order to overcome these obstacles, the viability of a variety of more convenient fuels was experimentally assessed based on criteria such as combustion stability, lean limit and emission levels. The prechamber fuels tested were liquefied petroleum gas (LPG), natural gas, reformed gasoline and carbon monoxide. Additionally, LPG was employed as the main fuel in conjunction with H2 or LPG in the prechamber. Furthermore, the effects of HAJI operation under sufficient exhaust gas recirculation to allow stoichiometric fuel-air supply, thus permitting three-way catalyst application were also examined. / In addition to experiments, prechamber and main chamber flame propagation modeling was completed to examine the effects of each prechamber fuel on the ignition of the main fuel, which consisted of either LPG or gasoline. The modeling and experimental results offered similar trends, with the modeling results giving insight into the physiochemical process by which main fuel combustion is initiated in the HAJI process. / Both the modeling and experimental results indicate that the level of ignition enhancement provided by HAJI is highly dependent on the generation of chemical species and not solely on the energy content of the prechamber fuel. Although H2 was found to be the most effective fuel, in a study of a very light load condition (70 kPa MAP) especially when running in the ultra-lean region, the alternative fuels were effective at running between λ = 2-2.5 with almost zero NOx formation. These lean limits are about twice the value possible with spark ignition (λ = 1.25) in this engine at similar load conditions. In addition, the LPG results are very encouraging as they offer the possibility of a HAJI like system where a commercially available fuel is used as both the main and prechamber fuel, while providing thermal efficiency improvements over stoichiometric operation and meeting current NOx emission standards.
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Location of Refueling Stations for Alternative Fuel Vehicles Considering Driver Deviation Behavior and Uneven Consumer Demand: Model, Heuristics, and GISJanuary 2010 (has links)
abstract: Concerns about Peak Oil, political instability in the Middle East, health hazards, and greenhouse gas emissions of fossil fuels have stimulated interests in alternative fuels such as biofuels, natural gas, electricity, and hydrogen. Alternative fuels are expected to play an important role in a transition to a sustainable transportation system. One of the major barriers to the success of alternative-fuel vehicles (AFV) is the lack of infrastructure for producing, distributing, and delivering alternative fuels. Efficient methods that locate alternative-fuel refueling stations are essential in accelerating the advent of a new energy economy. The objectives of this research are to develop a location model and a Spatial Decision Support System (SDSS) that aims to support the decision of developing initial alternative-fuel stations. The main focus of this research is the development of a location model for siting alt-fuel refueling stations considering not only the limited driving range of AFVs but also the necessary deviations that drivers are likely to make from their shortest paths in order to refuel their AFVs when the refueling station network is sparse. To add reality and applicability of the model, the research is extended to include the development of efficient heuristic algorithms, the development of a method to incorporate AFV demand estimates into OD flow volumes, and the development of a prototype SDSS. The model and methods are tested on real-world road network data from state of Florida. The Deviation-Flow Refueling Location Model (DFRLM) locates facilities to maximize the total flows refueled on deviation paths. The flow volume is assumed to be decreasing as the deviation increases. Test results indicate that the specification of the maximum allowable deviation and specific deviation penalty functional form do have a measurable effect on the optimal locations of facilities and objective function values as well. The heuristics (greedy-adding and greedy-adding with substitution) developed here have been identified efficient in solving the DFRLM while AFV demand has a minor effect on the optimal facility locations. The prototype SDSS identifies strategic station locations by providing flexibility in combining various AFV demand scenarios. This research contributes to the literature by enhancing flow-based location models for locating alternative-fuel stations in four dimensions: (1) drivers' deviations from their shortest paths, (2) efficient solution approaches for the deviation problem, (3) incorporation of geographically uneven alt-fuel vehicle demand estimates into path-based origin-destination flow data, and (4) integration into an SDSS to help decision makers by providing solutions and insights into developing alt-fuel stations. / Dissertation/Thesis / Ph.D. Geography 2010
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Feasibility study of using electric vehicles for game viewing in South AfricaDinodimos, Nicolaos 10 1900 (has links)
The purpose of the study is to analyze the energy use of battery electric vehicles (BEVs), to compare their energy usage with other different vehicle technologies, and ultimately to determine their suitability for recreational use.
The possibility of applying such vehicles into South Africa’s game reserves is researched in terms of energy costs and evaluated. Calculations were made based on actual existing routes found in the Kruger National Park, and are presently used by tourists for sightseeing and to access the different camps within the park.
Calculations were made on the forces acting on a vehicle driving through the different routes and terrains. These forces were then translated into fuel or energy consumption and subsequently into fuel and energy prices. The entire exercise was performed on alternative vehicle technologies in a hypothetical scenario.
The calculations investigated the energy consumption and efficiency of a battery electric vehicle (BEV) and other vehicle technologies such as fuel cell electric vehicle (FCEV), hybrid electric vehicle (HEV), and lastly the internal combustion engine (ICEV) vehicle.
It was found that the energy consumption of each vehicle technology revealed similar trends and ranking on most routes.
However on certain routes, the energy usage difference amongst the different vehicle technologies became more pronounced. This can be attributed to the continuous demand of energy by the vehicle to maintain forward motion.
It was found that in general, irrespective of the route profile, the route surface or its total distance, the highest energy efficiency is achieved by the battery electric vehicle (BEV), followed by the fuel cell electric vehicle (FCEV) and then by the combined hybrid electric vehicle (HEV) and lastly by the internal combustion engine (ICEV) vehicle. / Electrical Engineering / M. Tech. (Electrical Engineering)
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The Transition to Alternative Fuel Vehicles (AFVs): an Analysis of Early Adopters of Natural Gas Vehicles and Implications for Refueling Infrastructure Location MethodsJanuary 2015 (has links)
abstract: Alternative fuel vehicles (AFVs) have seen increased attention as a way to reduce reliance on petroleum for transportation, but adoption rates lag behind conventional vehicles. One crucial barrier to their proliferation is the lack of a convenient refueling infrastructure, and there is not a consensus on how to locate initial stations. Some approaches recommend placing stations near where early adopters live. An alternate group of methods places stations along busy travel routes that drivers from across the metropolitan area traverse each day. To assess which theoretical approach is most appropriate, drivers of compressed natural gas (CNG) vehicles in Southern California were surveyed at stations while they refueled. Through GIS analysis, results demonstrate that respondents refueled on the way between their origins and destinations ten times more often than they refueled near their home, when no station satisfied both criteria. Freeway interchanges, which carry high daily passing traffic volumes in metropolitan areas, can be appropriate locations for initial stations based on these results. Stations cannot actually be built directly at these interchange sites, so suitable locations on nearby street networks must be chosen. A network GIS method is developed to assess street network locations' ability to capture all traffic passing through 72 interchanges in greater Los Angeles, using deviation from a driver's shortest path as the metric to assess a candidate site's suitability. There is variation in the ability of these locations to capture passing traffic both within and across interchanges, but only 7% of sites near interchanges can conveniently capture all travel directions passing through the interchange, indicating that an ad hoc station location strategy is unlikely to succeed. Surveys were then conducted at CNG stations near freeway interchanges to assess how drivers perceive and access refueling stations in these environments. Through comparative analysis of drivers' perceptions of stations, consideration of their choice sets, and the observed frequency of the use of a freeway to both access and leave these stations, results indicate that initial AFV stations near freeway interchanges can play an important role in regional AFV infrastructure. / Dissertation/Thesis / Doctoral Dissertation Geography 2015
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Performance testing of a diesel engine running on varying blends of jatropha oil, waste cooking oil and diesel fuelSinuka, Yonwaba January 2016 (has links)
Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2016. / The high cost of fossil fuels and the fact that the world has arguably reached its peak oil production, has driven the need to seek alternative fuel sources.
The main objective of the current study is to determine the performance of a laboratory-mounted diesel engine when fuelled with varying laboratory prepared biofuel and biodiesel and whether the advancement of the injection timing parameters will improve the engine power output and improve the smoke effect of these different fuel blends. The laboratory prepared biofuels used in this project range from 100% bio-fuel (BF100) to 50%, 30% and 10% biodiesel blends (BF50, BF30 and BF10, respectively). It should be noted that these blends are not commercially available, since they were blended in the laboratory specifically for these tests. The overall results of the study show that there is a distinct opportunity for using certain bio-fuel blends in specific applications as the power outputs are no more than one quarter less than that of base diesel. Concomitantly, the smoke opacity in all of the blends is lower than that of base diesel, which is a significant benefit in terms of their overall air emissions.
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O gas natural e a matriz de insumo produto / Natural gas and the imput-otput matrixCarvalho, Marcelo Luis 13 July 2006 (has links)
Orientador: Sinclair Mallet-Guy Guerra / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-07T07:08:17Z (GMT). No. of bitstreams: 1
Carvalho_MarceloLuis_M.pdf: 1235405 bytes, checksum: ae801be721ef7d6c3b5165c90f09aae5 (MD5)
Previous issue date: 2006 / Resumo: O principal objetivo deste trabalho é a avaliação das perspectivas de uso do gás natural (GN) como combustível alternativo para o mercado nacional, e, dentro das possibilidades, sintetizar as principais estimativas de seu crescimento utilizando a matriz de insumo-produto. O gás natural desempenha papel interessante em diversas matrizes energéticas mundiais e pode-se dizer que o mesmo ocorre no Brasil, onde os problemas relacionados ao racionamento de energia elétrica, levaram à opção pelo produto que, entre outras características, apresenta custo viável e baixos índices de poluição atmosférica, principalmente emissão de monóxido de carbono (CO), um dos elementos de destaque na discussão de questões ambientais / Abstract: The main objective of this work is the assessment of the perspectives of the natural gas (NG) as an alternative fuel to the national market, and according to the possibilities synthesize the estimates of his growth. Nowadays the natural gas is an important piece in several energetic matrices around the world and is possible to say that the same happens in Brazil, where the problems related to the electricity supply suggests the option for the product that presents viable cost and low indexes of atmospheric pollution, mainly carbon monoxide emission (CO), one of the prominence elements in the discussion of environmental subjects / Mestrado / Mestre em Planejamento de Sistemas Energéticos
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Přepracování fermentačních zbytků z bioplynové stanice na alternativní palivo metodou biosušení / Production of an alternative fuel from digestate using bio-drying methodRákosník, Vítězslav January 2017 (has links)
Biogas represents one of the renewable sources of energy, which has been growing on use rapidly over the past decades. Biogas is produced during anaerobic digestion of organic material in biogas plants and it is most frequently used for heat and electricity production purposes. There are still plenty of unresolved questions as it is with the other renewable sources of energy. One of the most actual topics is the question of the subsequent usage of a digestate - side product of the biogas production process. Digestate is generally applied as an organic fertilizer for farmlands, but there are tendencies to use its solid phase for another energy producing processes or eventually as farm animal bedding, which is unfortunately connected with few problematic aspects such as transportation and storing of the biologically unstable material with high amount of water in it. Answer to those challenges could be provided by the bio-drying of the digestate's solid phaze - substrate is dried up by heat produced during the microbial decomposition of organic matter and artificial aeration. The main objective of the experimental part of this thesis was to comprehensively test the process of bio-drying of unmodified solid phase of digestate from different biogas plants with agricultural origin for the purpose of...
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Liquid Nitrogen Propulsion Systems for Automotive Applications: Calculation of Mechanical Efficiency of a Dual, Double-acting Piston Propulsion SystemNorth, Thomas B. 05 1900 (has links)
A dual, double-acting propulsion system is analyzed to determine how efficiently it can convert the potential energy available from liquid nitrogen into useful work. The two double-acting pistons (high- and low-pressure) were analyzed by using a Matlab-Simulink computer simulation to determine their respective mechanical efficiencies. The flow circuit for the entire system was analyzed by using flow circuit analysis software to determine pressure losses throughout the system at the required mass flow rates. The results of the piston simulation indicate that the two pistons analyzed are very efficient at transferring energy into useful work. The flow circuit analysis shows that the system can adequately maintain the mass flow rate requirements of the pistons but also identifies components that have a significant impact on the performance of the system. The results of the analysis indicate that the nitrogen propulsion system meets the intended goals of its designers.
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Alternativní pohon zdvihového mechanismu nízkozdvižného vozíku / Alternative drives lifting mechanism for pallet truckKorčián, Michal January 2010 (has links)
This thesis discusses the design replacement solution current hydraulic actuator stroke for low-lift truck to be completely electric. The aim is to propose the most optimal compensation due to the conservation of existing properties. To use this truck transportation in industries where the emphasis on increased health protection from potential leaks operating fluids.
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