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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Porovnání koncepcí hybridního pohonu v režimu denního dojíždění do práce / Comparison of Hybrid Powertrain Topologies in Daily Commuting Regime

Ušiak, Michal January 2020 (has links)
The master’s thesis deals with modelling of various architectures of hybrid powertrains for three vehicle sizes in GT-SUITE and compares them in daily commuting operating mode. On top of making of the hybrid vehicle simulation models, control algorithms had to be created to manage the energy split between the internal combustion engine and the electric motor for each of the architectures. Routes to work and back were logged using the GPS and postprocessed to obtain the speed and the road grade profiles. Resulting data was used as an input in simulations of daily commuting. To compare all hybrid powertrain architectures, fuel economy and electricity consumption were evaluated for WLTP and daily commuting operating modes. Finally, the environmental impact of each topology was assessed based on an estimation of corresponding well-to-wheel emissions.
12

Konsekvenser av vätgasproduktion för fordonsdrift : klimatpåverkan och energieffektivitet för olika produktionsvägar för vätgas jämfört med fordonsgas och vindkraftsel producerat av energibolag i Östergötland / Consequenses for hydrogen production for vehicles : climate influence and energy efficiency for different hydrogen production pathways compared with biogas and electricity from windmills produced by an energy company in Östergötland

Lilja, Dennis January 2019 (has links)
Sedan 2016 har flera politiska incitament genomförts för att undersöka möjligheten för att få den nordiska vätgasmarknaden att växa. Vätgas är en energibärare med potential att användas som ett miljövänligt drivmedelsalternativ för transportflottan eftersom utsläppen vid användning med bränslecell är rent vatten och bränslecellsbilar har en hög energieffektivitet i jämförelse med bilar med traditionella förbränningsmotorer. De enda utsläppen som förknippas med vätgas är de som sker i samband med produktionen av gasen. Det finns flera olika sätt att producera vätgas ur olika substrat. Idag produceras den mesta vätgasen från naturgas på raffinaderier för användning i bensin- och dieselproduktion. Det planeras en expansion av tankstationer för vätgas i Sverige, men då det finns få producenter så finns det ett intresse för Tekniska verken i Linköping AB att undersöka vad olika produktionsvägar för vätgas har för fördelar och nackdelar i jämförelse med andra biodrivmedel som fordonsgas och elektricitet. Studiens syfte var att undersöka tekniskt lämpliga produktionsvägar för vätgas som är kompatibla med biogasproduktion eller vindkraftsel, och jämföra de olika produktionsvägarna med biogas och vindkraftsel i relation till klimatpåverkan och energieffektivitet då drivmedel för 100 km körsträcka produceras. Efter en teknisk screening av vätgasproduktion, biogasproduktion och elektricitet från vindkraft konstanterades att vätgasproduktion viaångreformering av biogas, tvåstegsrötning av organiskt avfall och PEM-elektrolys är de produktionsvägar som har bäst potential för miljövänlig vätgasproduktion hos Tekniska verken i Linköping AB. Vidare kartlades viktiga parametrar för modellering och simulering av klimatpåverkan i programvaran simaPro. För jämförelse av produktionsvägarna för vätgas från rötning av matavfall användes WTW-metodik. För jämförelsen mellan elektricitet och elektrolys användes modifierad LCA-metodik med klimatpåverkan för hela livscykeln för vindkraftverket men för resterande processteg användes endast klimatpåverkan för driften för produktionen. Resultaten för jämförelsen mellan produktion av biogas, ångreformering och tvåstegsrötning visar ingen tydlig skillnad i varken klimatpåverkan eller energieffektivitet. Studien påvisar däremot att ångreformering av fordonsgas behöver mindre mängd matavfall för produktion av drivmedel för 100 km körsträcka (38 kg/100km) i jämförelse med tvåstegsrötning (44 kg/100km) och biogas (54 kg/100 km). För jämförelsen mellan produktion av vätgas via elektrolys och vindkraftsel visades systemet för vindkraftsel (23,6 kWh/100 km) vara dubbelt så energieffektivt jämfört med systemet för elektrolys (50,9 kWh/100 km), medan systemens klimatpåverkan förhöll sig till en liknande ratio med 0,154 kg CO2-eq utsläpp/100 km i jämförelse med 0,343 kg CO2-eq utsläpp/100 km. Studien visar att vid analys av energieffektivitet och klimatpåverkan för närbesläktade produktionssystem så spelar energieffektiviteten i använd bil stor roll för resultatet. Studiens resultat är framförallt intressant för svenska energibolag som vill veta mer om vätgasproduktion och hur dess klimatnytta och energiproduktion förhåller sig till andra fossilfria drivmedel.
13

Energy input, carbon intensity, and cost for ethanol produced from brown seaweed

Philippsen, Aaron 15 January 2013 (has links)
Brown macroalgae or brown seaweed is a promising source of ethanol that may avoid the challenges of arable land use, water use, lignin content, and the food vs. fuel debate associated with first generation and cellulosic ethanol sources; however, this promise is challenged by seaweed’s high water content, high ash content, and natural composition fluctuations. Notably, lifecycle studies of seaweed ethanol are lacking in the literature. To address this gap, a well-to-wheel model of ethanol production from farmed brown seaweed was constructed and applied to the case of Saccharina latissima farming in British Columbia (BC), Canada, to determine energy return on energy invested (EROI), carbon intensity (CI), and near shore seaweed farming production potential for seaweed ethanol and to examine the production cost of seaweed ethanol. Seaweed farming and ethanol production were modeled based on current BC farming methods and the dry grind corn ethanol production process; animal feed was included as an ethanol co-product, and co-product credits were considered. A seaweed ethanol yield calculation tool that accounts for seaweed composition was proposed, and a sensitivity study was done to examine case study data assumptions. In the case study, seaweed ethanol had lower CI than sugarcane, wheat, and corn ethanol at 10.1 gCO2e/MJ, and it had an EROI comparable to corn ethanol at 1.78. Seaweed ethanol was potentially profitable due to significant revenue from animal feed sales; however, the market for seaweed animal feed was limited by the feed’s high sodium content. Near shore seaweed farming could meet the current demand for ethanol in BC, but world near shore ethanol potential is likely an order of magnitude lower than world ethanol production and two orders of magnitude lower than world gasoline production. Composition variation and a limited harvest season make solar thermal or geothermal seaweed drying and storage necessary for ethanol production in BC. Varying seaweed composition, solar thermal drying performance, co-product credits, the type of animal feed produced, transport distances, and seaweed farming performance in the sensitivity study gave an EROI of over 200 and a CI of -42 gCO2e/MJ in the best case and an EROI of 0.64 and CI of 33 gCO2e/MJ in the worst case. Co-product credits and the type of animal feed produced had the most significant effect overall, and the worst cases of seaweed composition and solar thermal seaweed drying system performance resulted in EROI of 0.64 and 1.0 respectively. Brown seaweed is concluded to be a potentially profitable source of ethanol with climate benefits that surpass current ethanol sources; however, additional research into seaweed animal feed value, co-product credits, large scale seaweed conversion, and the feasibility of solar thermal or geothermal seaweed drying is required to confirm this conclusion. / Graduate
14

Investigating The Suitability of Electrified Powertrain Alternatives for Refuse Trucks with Emphasis in The City of Hamilton

Toller, Jack 11 1900 (has links)
Refuse trucks, commonly referred to as garbage trucks are a critical component of a municipality’s waste management industry. Their primary purpose is to collect, transport and deposit waste from households or businesses to designated transfer sites or dumps. Historically, refuse trucks have been powered by diesel fuel. The consumption of diesel fuel paired with the frequent accelerations or decelerations between each residential household along a route attribute to high amounts of tailpipe emissions and noise pollution within neighbourhoods. There is significant opportunity to explore avenues of powertrain electrification in refuse trucks to reduce their emissions and improve energy efficiency. To rapidly test promising powertrains, vehicle software models were developed. To accurately model the energy usage and power requirements of refuse trucks, environments for the models to operate were created. The environments were created using on-board diagnostic and positional data collected from refuse trucks in the City of Hamilton in Ontario, Canada. The data collection was done under a research collaboration between the City of Hamilton and the McMaster Automotive Resource Centre. The approaches used to develop the drive and duty cycles for the vehicle models offer some innovative approaches without the need for invasive devices to be installed. The powertrains that were modelled includes an all-electric, ranged extended electric and conventional refuse trucks. A comparative analysis of the pump-to-wheel powertrain efficiencies were completed looking at metrics such as fuel economy, payload capacity and fuel costs. Lastly, a look at truck emissions from a well-to-wheel perspective were completed to investigate the impact of each powertrain on greenhouse gasses and the effect on air quality of their immediate surroundings. / Thesis / Master of Applied Science (MASc)
15

Impacts of Driving Patterns on Well-to-wheel Performance of Plug-in Hybrid Electric Vehicles

Raykin, Leonid 27 November 2013 (has links)
The well-to-wheel (WTW) environmental performance of plug-in hybrid electric vehicles (PHEVs) is sensitive to driving patterns, which vary within and across regions. This thesis develops and applies a novel approach for estimating specific regional driving patterns. The approach employs a macroscopic traffic assignment model linked with a vehicle motion model to construct driving cycles, which is done for a wide range of driving patterns. For each driving cycle, the tank-to-wheel energy use of two PHEVs and comparable non-plug-in alternatives is estimated. These estimates are then employed within a WTW analysis to investigate implications of driving patterns on the energy use and greenhouse gas emission of PHEVs, and the WTW performance of PHEVs relative to non-plug-in alternatives for various electricity generation scenarios. The results of the WTW analysis demonstrate that driving patterns and the electricity generation supply interact to substantially impact the WTW performance of PHEVs.
16

Impacts of Driving Patterns on Well-to-wheel Performance of Plug-in Hybrid Electric Vehicles

Raykin, Leonid 27 November 2013 (has links)
The well-to-wheel (WTW) environmental performance of plug-in hybrid electric vehicles (PHEVs) is sensitive to driving patterns, which vary within and across regions. This thesis develops and applies a novel approach for estimating specific regional driving patterns. The approach employs a macroscopic traffic assignment model linked with a vehicle motion model to construct driving cycles, which is done for a wide range of driving patterns. For each driving cycle, the tank-to-wheel energy use of two PHEVs and comparable non-plug-in alternatives is estimated. These estimates are then employed within a WTW analysis to investigate implications of driving patterns on the energy use and greenhouse gas emission of PHEVs, and the WTW performance of PHEVs relative to non-plug-in alternatives for various electricity generation scenarios. The results of the WTW analysis demonstrate that driving patterns and the electricity generation supply interact to substantially impact the WTW performance of PHEVs.

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