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1

Brown, Gareth D. "Assessing the greenhouse gas emissions of transport biofuels." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9823.

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Many fuel cycle greenhouse gas (GHG) emissions assessments of varying scope, detail and methodology have been carried out for various biofuels in recent years, and these have largely concluded that biofuels provide GHG reduction benefits as substitutes for fossil fuels. As more attention is focused on biofuels, however, doubts have been raised about the reliability of previous GHG assessments of these fuels. From a scientific perspective, three main observations give reason to doubt these assessments: 1. There are widely varying results for what appear to be identical fuels. 2. The assessment methodologies involve inherently subjective elements. 3. There is still significant scientific uncertainty in characterisations of important processes that need to be accounted for in most GHG assessments of biofuels. For accurate determination of the GHG emissions impacts of biofuels, there is a need for further development of standardised, demonstrably reliable assessment methods. This research investigates methods used for assessing net GHG emissions from biofuels. It identifies remaining methodological deficiencies that prevent the generation of definitive results. A methodological framework is developed for optimising the reliability of biofuel GHG assessments within the limits of currently available knowledge and methods, and the most important developments required for extending those limits are identified. A new calculation tool and database are developed to facilitate the carrying out of biofuel GHG assessments with optimal reliability. It is concluded that uncertainties associated with existing GHG assessments can significantly limit our ability to draw firm conclusions from comparisons of GHG impacts among biofuels and between biofuels and fossil fuels. Reliable GHG assessments of biofuels require very precise specifications of the systems being described, with clear definitions of the limitations of applicability of the assessment results, explanations of the methodological choices adopted and their implications, and acknowledgement of the limits set by all relevant scientific uncertainty.
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Mongoma, Thabo. "Regulatory uncertainty and transport biofuels investments in South Africa." Diss., University of Pretoria, 2015. http://hdl.handle.net/2263/52262.

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This paper investigates the impact of regulatory uncertainty on the development of the South African transport biofuels industry. A qualitative research methodology was used to study investor behavior in response to conditions of continued regulatory uncertainty. The sample included key members of the South African transport biofuels value chain, including; major oil companies, biofuels manufacturers and the applicable government agencies. The collected field data was analysed against literature on investments under conditions of uncertainty, the South African petroleum products pricing principles and global best practices in the transport biofuels sector. Amongst others, the results revealed that continued regulatory uncertainty impacts investor confidence negatively, delays investments and where investors have considerable market power, they do not conform to institutional pressure.
Mini Dissertation (MBA)--University of Pretoria, 2015.
ms2016
Gordon Institute of Business Science (GIBS)
MBA
Unrestricted
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3

Martin, Michael A. "Sustainable transportation with Biofueled Public Transport : Stockholm example and Application of Biofuels in a French Municipality." Thesis, KTH, Industriell ekologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32800.

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Solutions to the current calamity of fossil fuels are becoming more urgent with each moments passing. It is not news for those in technical professions as well as many others, that reserves of oil are diminishing and prices for petroleum based products are increasing. A most transparent option exists today, and is becoming exploited by many countries worldwide. This solution answers to the title of biofuels, consisting of gases, liquids and even biomass for various energy requirements. Two biofuels in particular hold precedence with regard to transportation fuels, namely biodiesel and ethanol, and have been studied in the following report. The said fuels are produced by transesterification of oils and fermentation of sugar based crops respectively, for use in transport fleets worldwide. Stockholm, Sweden is in the forefront for use of the said fuels in their public transportation sector, with nearly the entire fleet fueled with ethanol. Persistence, extensive research and unprecedented environmental support equate to the success of this fuel, which is used competitively to petroleum diesel, while including reduced environmental impacts. Other cities in Europe also have similar capacities to utilize biofuels, although some have failed to hold to this technology. Troyes, France, the home of CREIDD (Center of Research and Interdisciplinary Studies on Sustainable Development) and UTT (University of Technology of Troyes), has been further studied to produce the relative measures needed for biofuel implementation in this municipality, while generating the impacts toward the environment and municipality in the form of costs, emissions and savings. Surprisingly, and hereafter, it has been concluded that the use of biodiesel, and not ethanol like Stockholm, offers the best course of action for Troyes both economically and environmentally. Cities throughout Europe can follow suit and discover the biofuel most applicable to their locality and promote further sustainability, although the question still arises of whether biofuels are indeed sustainable.
www.ima.kth.se
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4

Ersson, Carolina. "Conditions for resource-efficient production of biofuels for transport in Sweden." Licentiate thesis, Linköpings universitet, Industriell miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-106651.

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Transportation has continued to increase worldwide and fossil-fuel dependency is strong which leads to a number of problems, e.g. increased emissions of green-house gases (GHG) and risks related to energy security. Biofuels have until now been one of the few renewable alternatives which have been able to replace fossil fuels on a large scale. The biofuel share in relation to the total use of fuel in the transportation sector is still small, but in many places in the world political targets are set to increase the share of renewable fuels, of which biofuels are supposed to be an important part. Within the European Union targets for renewable energy have been set, including within the transportation sector, where 10% shall come from renewable sources by 2020 according to the EU Renewable Energy Directive (EU RES). Biofuels also need to fulfill the sustainability criteria in the EU RES, to be regarded as renewable. Depending on how biofuels are produced their resource efficiency varies, and the differences in environmental and economic performance can for instance be significant. The aim of this thesis is to describe and analyze conditions for a development towards increased and more resource-efficient production of biofuels in Sweden. The conditions have been studied from a regional resource perspective and from a biofuel producer perspective since it has been assumed that the producers are in possession of important knowledge, and potentially will play an important role in future biofuel development. The concept of resource efficiency used in this thesis includes an environmental and economic perspective as well as an overall societal dimension to some extent. The region of Östergötland in Sweden was used for the assessment of the resourcefocused biofuel potential for the year 2030, where two scenarios based on assessments regarding socio-technical development in relation to regional resources were used. The scenarios were based on semi-structured interviews with biofuel actors, literature studies and information from experts in the field. In the EXPAN (Expansion) scenario a continued development in line with the current one was assumed, but also an increased availability of feedstock primarily within the agricultural and waste sectors (also including byproducts from industry) for biofuel production. In the INNTEK (Innovation and Technology development) scenario greater technological progress was assumed to also enable the use of some unconventional feedstock besides increased available arable land and improved collection/availability of certain feedstock. Biomass feedstock from four categories was included in the potential: waste, agriculture, forestry and aquatic environments. One important feedstock which was not included in this study, but which is often included in studies of potential, is lignocellulosic material from the forest. This choice was also supported by the regional actors who judged it as less probable that there will be any large-scale use of such feedstock for biofuels in this region within the given timeframe. Regarding arable land available for biofuel production a share of 30% was assumed at maximum in the region, of which 15% is already used for cereal production for ethanol fuel. On these additional 15% assumed to be available for biofuel production year 2030, ley cropping for production of biogas was assumed in this study. Aquatic biomass is often not included in biofuel potentials. Here, algae were assumed to be a potentially interesting substrate for biogas production since harvesting algae in for instance the Baltic Sea could be seen as a multifunctional measure, i.e., contributing additional environmental benefits such as reducing eutrophication. Based on the assumption that the energy need in the transportation sector will be the same in 2030 as in 2010, up to 30% could be substituted with biofuels in the EXPAN scenario and up to 50% in the INNTEK scenario, without seriously conflicting with other interests such as food or feed production. In the study of potential, production systems for biogas production were   prioritized since such systems were judged to have a large potential for resource efficiency. This is because they have a big capacity to utilize by-products and waste as feedstock, and also because they can contribute to closing the loops of plant nutrients, seen as an important goal in society, if the digestate is returned to arable land. The utilization of by-products and waste however in many cases requires cooperation between different actors in society. Within the research field of industrial symbiosis, cooperation regarding material and energy flows is studied from different perspectives, e.g. how such cooperation between actors evolves and to what extent such cooperation can contribute to improving the environmental and economic performance of systems. Both these perspectives are interesting in relation to biofuels since production often involves a large number of energy- and material flows at the same time as resource efficiency is important. How the producers organize the production when it comes to feedstock, energy, by-products and products and what influences this is therefore interesting to study. In this thesis four biofuel producers of three different biofuels (ethanol, biodiesel and biogas) on the Swedish market were studied, focusing on how they organize their biofuel production in terms of e.g. their material and energy flows, and how they intend to organize it in the future. The study is based on semi-structured interviews with the biofuel producers as well as literature studies. In all the cases, a number of areas of material and energy flow cooperation were identified and it could also be concluded that there had been some change regarding these patterns over time. Looking into the future a clear change of strategy was identified in the ethanol case and partly also in the biodiesel case where a development towards improved valorisation and differentiation of by-product flows was foreseen. If such a “biorefinery” strategy is realized, it can potentially improve the economic viability and resource efficiency in these biofuel producers. In the biogas cases, instead a strategy to lower the costs for feedstock through the use of lower quality feedstock was identified. This strategy also has a potential to increase economic viability and improve the resource efficiency. However, the success of this strategy is to a large extent dependent on how the off-set of the biofertilizer can be arranged regarding the economic challenges that the biogas producers’ experience, and yet no strategy for implementation regarding this was identified. The EU Renewable Energy Directive was mentioned in relation to most cooperation projects and therefore regarded as an important critical factor. All of the studied companies also struggle to be competitive, for which reason the importance of the direct economic aspects of cooperation seems to increase.
Transporterna i världen ökar kontinuerligt och det fossila beroendet är fortsatt stort vilket medför flera problem, bl. a. ökade utsläpp av växthusgaser och en osäkerhet kring framtidens energiförsörjning. Biodrivmedel har hittills varit ett av de få förnyelsebara alternativ som kunnat ersätta fossila drivmedel i stor skala. Andelen biodrivmedel av den totala bränsleanvändningen inom transportsektorn är dock fortfarande liten, men på många håll i världen finns nu politiska mål för att öka andelen förnyelsebara drivmedel av vilka biodrivmedel förväntas utgöra en viktig del. Inom EU har mål för förnybar energi satts upp bl. a. inom transportsektorn där 10% skall komma från förnybara energikällor senast år 2020 enligt EUs förnybarhetsdirektiv. Biodrivmedel måste dessutom, om de ska räknas som förnyelsebara, uppfylla direktivets hållbarhetskriterier. Beroende på hur biodrivmedel produceras är de olika resurseffektiva, med exempelvis betydande skillnader avseende miljömässig och ekonomisk prestanda. Syftet med den här avhandlingen är att beskriva och analysera förutsättningarna för en utveckling mot ökad och mer resurseffektiv produktion av biodrivmedel i Sverige. Förutsättningarna har studerats med ett regionalt resursperspektiv samt från ett  biodrivmedelsproducentperspektiv eftersom producenterna sitter på viktiga kunskaper och sannolikt spelar en betydande roll för den framtida utvecklingen. Resurseffektivitetsbegreppet som används i den här avhandlingen inkluderar ett miljömässigt och ett ekonomiskt perspektiv liksom ett övergripande samhälleligt perspektiv. När det gäller ett regionalt resursperspektiv har Östergötland använts för att med hjälp av två scenarier för år 2030 ta fram en biodrivmedelspotential utifrån en bedömning av en socio-teknisk utvecklingspotential i förhållande till regionala resurser. Scenarierna togs fram med hjälp av semistrukturerade intervjuer med aktörer i branschen, litteraturstudier och i vissa fall med hjälp av sakkunniga. I scenario EXPAN (expansionsscenario) antogs en fortsatt teknikutveckling i linje med den hittills-varande och en samtidig ökning av tillgängligheten av potentiella resurser inom framförallt jordbrukssektorn och avfallssektorn (inkluderat också restproduktsresurser inom industrin) för biodrivmedelsproduktion. I scenario INNTEK (Innovations och teknikutvecklingsscenario) har utöver ytterligare antagen tillgänglig jordbruksmark också större tekniksprång antagits som möjliggör användning av icke konventionella råvaror för biodrivmedelsproduktion, samt förbättrad insamling/tillgängliggörande av vissa råvaror. I potentialen har biomassa från fyra olika sektorer inkluderats; avfall, jordbruk, skogsbruk och akvatiska miljöer. En viktig biomassaresurs som inte inkluderats i denna potentialstudie, men som vanligen inkluderas i potentialstudier, är lignocellulosarika material från skogen. Detta var ett val som också stöddes av de regionala aktörerna som i den här studien bedömde det som mindre sannolikt att någon storskalig användning av sådana råvaror kommer att finnas i regionen inom den aktuella tidsramen. När det gäller jordbruksmark som kan utnyttjas för bioenergiproduktion så har en andel på 30% antagits, varav 15% redan idag utnyttjas till spannmålsodling för produktion av etanol. På de ytterligare 15% som antas kunna tas i anspråk för biodrivmedelsändamål år 2030, har vallodling för biogasändamål antagits i denna studie. Akvatisk biomassa ingår ofta inte i bioenergipotentialstudier, men har inkluderats här eftersom alger skulle kunna vara ett intressant substrat för biogasproduktion, men också för att algskörd i akvatiska miljöer skulle kunna ses som en multifunktionell åtgärd med ytterligare miljönytta som t.ex. minskad övergödning i Östersjön. Med antagandet att energibehovet inom transportsektorn blir lika stort år 2030 som år 2010, skulle upp till 30% av de fossila drivmedlen kunna ersättas av biodrivmedel i scenario EXPAN och upp till 50% i scenario INNTEK, utan att större intressekonflikter skulle uppstå i förhållande till andra behov såsom mat eller foderproduktion. I potentialstudien har vidare produktionssystem för biogas prioriterats eftersom sådana system bedömdes ha stor potential när det gäller resurseffektivitet. Först och främst för att de har stor kapacitet när det gäller användning av restprodukter, men också för att de kan bidra till att sluta kretsloppet av växtnäringsämnen om rötresten återförs till åkermark. Nyttiggörande av restprodukter och avfall kräver emellertid i många fall samarbete mellan olika aktörer i samhället. Inom forskningsfältet industriell symbios studerar man bl. a. hur samarbeten kring energi- och materialflöden mellan aktörer uppstår och i vilken utsträckning samarbetsgraden kan bidra till att förbättra miljöprestandan och ekonomiska prestanda i systemen. Dessa perspektiv är intressanta i förhållande till biodrivmedel eftersom produktionen av dessa är förknippad med ett stort antal energi- och materialflöden samtidigt som resurseffektiviteten är viktig. Hur biodrivmedelsproducenterna organiserar produktionen när det gäller råvaror, energi, biprodukter och produkter och vad som styr detta är därför intressant att studera. I den här avhandlingen studerades hur fyra svenska biodrivmedelsproducenter för tre olika biodrivmedel (etanol, biodiesel och biogas) på den svenska marknaden har organiserat sin produktion, med fokus på energi- och materialflöden, samt hur de planerar att organisera den framöver. Studien baseras framförallt på semi-strukturerade intervjuer med aktörerna samt litteraturstudier. I samtliga fyra fall kunde ett antal samarbeten kring bl.a. material och energiflöden kartläggas samt hur dessa förändrats över tiden. När det gäller framtiden kunde en tydlig strategiomläggning ses i etanolfallet och delvis i biodieselfallet mot en valorisering och diversifiering av rest-/bi-produktflöden. Om denna ”bioraffinaderistrategi” lyckas kan den bidra till bättre lönsamhet och bättre resurseffektivitet. I biogasfallen fanns istället strategier för att försöka sänka råvarukostnader genom att hitta råvaror av lägre kvalitet. Också denna strategi kan öka lönsamheten och förbättra resurseffektiviteten, men detta förutsätter att avsättningen av biogödsel också kan lösas på ett lönsamt sätt. Detta är en fortsatt stor utmaning för biogasproducenterna. En av de viktigaste kritiska faktorerna för de olika samarbetsprojekten var EUs förnybarhetsdirektiv som nämndes i samband med de flesta samarbetsprojekt och som här sågs som en miljömässig drivkraft. Också det långsiktiga byggandet av gröna varumärken verkar vara en drivkraft, åtminstone när det gäller vissa samarbetsprojekt. Samtliga biodrivmedelsproducenter kämpar idag med lönsamheten varför också de ekonomiska aspekterna kring samarbeten är mycket väsentliga.
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Alex, Ansu. "Comparison study of various current and potential liquid biofuels in road freight transport : Application on a case study on Transport Centralen in Halmstad." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-33914.

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The role of liquid biofuels in transportation to minimize the effects of climate change is  evident and has led to a number of studies on finding effective solutions to replace fossil fuels. Liquid biofuels are especially important for heavy duty transports as the effective ‘green’ alternatives are not as many compared to light duty vehicles; for which for e.g. electrification is an option. This thesis presents a comparison study of 8 liquid biofuels with a total of 13 different fuel pathways for use in road freight transports; both current and potential future fuels are assessed in terms of their environmental effects, fuel properties and compatibility with the heavy duty vehicle engines (see Table 10, page 36). Furthermore, a case study is performed to assess the practicality of the results of the study.  Hydro-treated vegetable oil, Bio Dimethyl ether, Liquefied Bio Methane/ ED95 are identified as fuels with considerable potential in the shorter term. Algal biofuel and Biomass to liquid (BTL) fuels from synthesis gas, if realized commercially would be a breakthrough for biofuels in overall transportation sector. However, life cycle analysis has to be performed for the different fuel pathways to completely understand the various impacting factors.
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Magnusson, Mimmi. "Energy systems studied of biogas : Generation aspects of renewable vehicle fuels in the transport system." Doctoral thesis, KTH, Energiprocesser, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105120.

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The transport sector is seen as particularly problematic when concerns about climate change and dependency on fossil energy are discussed. Because of this, bioenergy is strongly promoted for use in the transport sector, both on a European level and nationally in Sweden. Even though bioenergy is considered one of the key solutions, it is generally agreed that both supply- and demand-side measures will be needed to achieve a change to a more sustainable transport system. One of the reasons for this is the limited availability of biomass, especially agricultural feedstocks competing with food or feed production. Woody biomass, however more abundant, is also exposed to tough competition from other sectors. In this thesis, the role of biogas as a vehicle fuel in a future sustainable transport system is discussed together with the prerequisites needed to realise such a transport system. Biogas is a biofuel that could be produced in several different ways: by anaerobic digestion, which is a first-generation production route, by gasification, which is a second-generation process, and by catalytic reduction of carbon dioxide, a third-generation technology. The main focus in this thesis is on biogas produced by anaerobic digestion and the results show that there is a significant potential for an increase compared to today’s production. Biogas from anaerobic digestion, however, will only be able to cover a minor part of the demand in the Swedish transport sector. Considering biogas of the second and third generations, the potential for production is more uncertain in a mid-term future, mainly due to competition for feedstock, the possibility to produce other fuels by these processes, and the present immaturity of the technology. The limited potential for replacing fossil vehicle fuels, either by biogas or other renewable fuels, clearly shows the need for demand-side measures in the transport system as well. This thesis shows the importance of technical and non-technical means to decrease the demand for transport and to make the transport as efficient as possible. The results show that both energy-efficient vehicles and behavioural and infrastructural changes will be required. Policies and economic incentives set by governments and decision-making bodies have a prominent role to play, in order to bring about a shift to a more sustainable transport system, however, measures taken on individual level will also have a great impact to contribute to a more sustainable transport system.

QC 20121116

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Islam, M. Munirul. "A review and analysis of sustainable issues related to liquid biofuels." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-260678.

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Most of the time when developing policies for the promotion of future biofuel, the social dimension of sustainable development is neglected. But it is important to incorporate both social and economic issues along with environmental issues for a successful sustainability strategy because sustainable development depends on all three aspects of sustainability. This paper focuses on the sustainable development of liquid biofuel for the transport sector.The global transport sector is booming as is the need for energy. With the growing concern about climate change, governments of developed countries have been implementing different policy directives to promote biofuel as an alternative source of energy. But strategies implemented to fulfill the target of mitigating effects of climate change have exposed negative effects of liquid biofuels on both environment and society. This paper reviewed information on liquid biofuels and their effects on environment, society and economy and analyzed them from a sustainable development point of view. Although scientists have developed biofuels through advanced technology that seem to have less negative effects than traditional biofuels, they are still on a trial basis. In addition to this the effects of these biofuels are also need to be tested on a commercial basis in order to ensure their sustainability. Due to these considerations the process of switching from traditional biofuel to advanced biofuels will require time. It is imperative to develop sustainable ways of production and use of available biofuels which do not harm nature or exploit vulnerable communities. Biofuel policies also need to be studied thoroughly in order to find weaknesses and pitfalls. Although numerous studies related to specific issue like indirect land use change, GHG emission, biofuel policies or the biofuel market etc. have been conducted, it is rare to find a study that takes into consideration of all three aspects (economy, society and environment) of sustainable development. After reviewing and analyzing the literature, this thesis has come to a conclusion that the potential of liquid biofuel in the future transport sector is unlimited. But due to the negative effects on environment and society it has not achieved sustainability. Moreover the expense of production and lack of investment in the sector has made it economically unsustainable. But, it is possible to change the scenario by implementing proper policies in a way that the social and environmental issues that happened in the past do not happen again and the sector can achieve sustainability.
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Lönnqvist, Tomas. "Biogas in Swedish transport – a policy-driven systemic transition." Doctoral thesis, KTH, Energiprocesser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-206578.

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The thesis analyzes the conditions for biogas in the Swedish transport sector. Biogas can contribute to the achievement of Sweden’s ambitious targets of decreased emissions of greenhouse gases and an increased share of renewables in the transport sector, a sector that encompasses the major challenges in the phase-out of fossil fuels. Biogas development has stagnated during recent years and there are several factors that have contributed to this. The use of biogas in transport has developed in niches strongly affected by policy instruments and in this thesis, the progress is understood as a policy-driven systemic transition. Biogas has (started to) become established at the regime level and has begun to replace fossil fuels. The major obstacles for continued biogas development are found to be the stagnated vehicle gas demand, the low predictability of Swedish policy instruments, and electric car development. Moreover, the current prolonged period of low oil prices has also contributed to a lack of top-down pressure. A large share of the cheap and easily accessible feedstock for conventional biogas production is already utilized and an increased use of vehicle gas could enable a commercial introduction of forest-derived methane. However, the technologies to produce forest-derived methane are still not commercial, although there are industrial actors with technological know-how. Future biogas development depends on how the policy framework develops. Policy makers should consider the dynamics of biogas as a young sociotechnical system where different system fronts develop at a varying pace. Currently the demand side is lagging behind. However, it is necessary to maintain predictable policy support throughout the entire biogas value chain, since the system fronts that lag can vary over time. The low predictability of Swedish policy instruments indicates that policy makers should exercise care in their design to create a more robust policy framework moving forward.

QC 20170508

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Forsberg, Göran. "Assessment of bioenergy systems : an integrating study of two methods /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5857-9.pdf.

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Nordin, Elin, and Emma Thiede. "Jämförelse mellan olika biodrivmedel för den kollektiva busstrafiken i Gävleborgs län : Miljö- och potentialbedömning av biodiesel, biogas och eldrift." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-21702.

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Fossila drivmedel ger en negativ påverkan på miljö och klimat. Men frågan är om biodrivmedel är bättre. Det kan skilja stort mellan olika drivmedel beroende på vilken råvara och framställningsprocess som används. Syftet med studien är att göra en sammanställning av fördelar och nackdelar med olika fossilfria drivmedel som används och kan komma att användas i kollektivtrafiken i Gävleborgs län. I samråd med X-trafik, den regionala kollektivtrafikmyndigheten, har det framkommit att det främst är biodiesel (HVO - hydrogenerade vegetabiliska oljor), biogas och el som är intressanta att analysera. Rapporten kommer att redogöra hur användningen ser ut i andra delar av landet och i världen för att kunna anpassa kunskaperna till Gävleborgs län. I studien ingår även en granskning av produktionspotentialen för dessa drivmedel i länet. Det slutgiltiga resultatet av studien kommer att bidra till utvecklingen av en fossilfri fordonsflotta i regionen. Genom intervjuer med närproducenter av biogas (Gästrike Ekogas AB) och biodiesel (Colabitoil AB) samt med X-trafik inhämtades kunskap om hur produktionen ser ut i länet och vilka behov som finns. Detta tillsammans med en litteraturstudie gav resultatet. X-trafik har huvudansvaret för kollektivtrafiken och utför den genom entreprenörer som fått uppdragen genom upphandling. HVO har många fördelar mot andra dieselbränslen och kan tankas direkt i fordonen utan att dessa behöver modifieras. Dessutom görs den HVO som Colabitoil distribuerar och kommer börja producera på restavfall. En av X-trafiks entreprenörer har slutit ett avtal med Colabitoil vilket betyder att all fossil diesel som bussarna kör på idag kommer att bytas ut mot biodiesel. I Gävle stad kör bussarna på biogas och gasen produceras på avloppsreningsverket Duvbacken. Denna produktion täcker upp 60 % av behovet och resten är fossil gas. Med den nya anläggningen som Gästrike Ekogas håller på att bygga kommer behovet mer än väl täckas upp. Biogasen är även den gjord på restavfall. I den nya biogasanläggningen kommer de också få en utmärkt biogödsel fri från föroreningar, som kan KRAV-märkas och användas till odling för att ersätta konstgödsel. Elbussar är något som diskuteras av X-trafik och kan vara bra alternativ på vissa linjer dock är tekniken under utveckling fortfarande och investeringskostnaden är hög. Det finns potential att kollektivtrafiken i Gävleborgs län kan köra på 100 % miljövänligt, hållbara och närproducerade drivmedel inom en snar framtid.
The purpose of this study is to make a summary of the advantages and disadvantages of various non-fossil fuels that are used and can be used in public transport in the county. In consultation with X-trafik, it has emerged that it is mainly biodiesel (in the form of  HVO - hydrogenated vegetable oils), biogas and electricity that are interesting to analyse. The report will describe the use in other parts of the country and the world to adapt the knowledge to the county. The study also includes an investigation of the production potential of these fuels within the county. The final results of the study will contribute to the development of a fossil free fleet in the region. Through interviews with local producers of biogas (Gästrike Ekogas AB) and biodiesel (Colabitoil AB) and X-trafik information was collected about how the production is performed in the county and what the needs are. This, together with a literature review yielded the results. X-trafik has the main responsibility for the public transport and carries it out through contractors with assignments through procurement. HVO has many advantages compared to other diesel fuels and can be refueled directly in vehicles without modifications of these. Additionally, the HVO that Colabitoil distributes and will begin producing is made of residual waste. One of X-Trafik's contractors has signed a contract with Colabitoil which means that all fossil diesel the buses run on today will be replaced with biodiesel. In Gävle city the buses run on biogas and the gas is produced at the sewage treatment plant. This production covers 60% of the need and the rest is fossil gas. The new facility, which Gästrike Ekogas is building, will produce more than the public transport needs. Biogas is also made from residual waste. The new facility will also yield a by-product in the form of an excellent bio-fertilizer free of contaminants that can be KRAV labelled and used for cultivation to replace chemical fertilizers. Electric buses are something that is discussed, and may be a good option on certain routes, however, the technology is still under development and the investment cost is high. There is great potential that the public transport in the county can run on 100% eco-friendly, sustainable and locally produced fuels in the near future.
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Rodríguez, Morales Jorge Ernesto, and López Fernando Rodríguez. "Regulation, agro-energy policy and market evolution for renewable fuels in Brazil." Pontificia Universidad Católica del Perú, 2015. http://repositorio.pucp.edu.pe/index/handle/123456789/116056.

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The costs of oil dependence, the environmental external costs of fossil fuels, or the promotion of agricultural development, has justified a number of measures of state intervention to expand the domestic market of biofuels, assuming that state intervention is necessary and sufficient condition for achieving this aim. After analyzing the political and economic elements in the Brazilian ethanol sector in historical perspective, in this article we argue that the expansion or contraction of the market should not be understood as an effect of a particular policies determined by the regulatory state. Regarding this, we argue the trends on the market development reflect the effects of aprevious underlying relationship, which is determined by the convergence or divergence over time of the opportunity costs of government and agribusiness. Our analysis shows that the effectiveness of a policy of energy diversification as the promotion of biofuels depends on the economic benefits and political rents generated by expanding the use of ethanol. These restrictions can be extrapolated as part of the cost-effectiveness analysis of public policies related to the sector in other countries.
Los costes de la dependencia del petróleo, los costes externos medioambientales de los combustibles fósiles, o la promoción del desarrollo agrícola, han justificado una serie de medidas de intervención estatal para expandir el mercado interno de los biocarburantes, en el supuesto de que la intervención del Estado es condición necesaria y suficiente para lograr este objetivo. Después de analizar en perspectiva histórica los elementos políticos y económicos en el sector del etanol de Brasil, en este artículo se argumenta que la expansión o contracción del mercado no debe entenderse como el efecto de unas políticas determinadas por el Estado regulador. En este sentido, sostenemos que las tendencias en el desarrollo del mercado reflejan los efectos de una relación subyacente anterior, que está determinada por la convergencia o divergencia en el tiempo de los costos de oportunidad del gobierno y de la agroindustria. Nuestro análisis muestra que la eficacia de una política de diversificación energética como la promoción de los biocombustibles depende de los beneficios económicos y de las rentas políticas generadas por la expansión del uso de etanol. Estas restricciones se pueden extrapolar como parte del análisis de costo-efectividad de las políticas públicas relacionadas con el sector en otros países.
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12

Nordström, Eeva-Liisa. "Fossilfri kollektivtrafik : En företags- och samhällsekonomisk kostnadsjämförelse av förnybara drivmedel för stadsbussar i Uppsala utifrån tre skattescenarier." Thesis, KTH, Energi och klimatstudier, ECS, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168393.

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13

Fischer, Robert. "Investigation into sustainable energy systems in Nordic municipalities." Licentiate thesis, Luleå tekniska universitet, Energivetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-78091.

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Municipal energy systems in Nordic environments face multiple challenges: the cold climate, large-scale industries, a high share of electric heating and long distances drive energy consumption. While actions on the demand side minimize energy use, decarbonization efforts in mining, industries, the heating and the transport sector can increase the consumption of electricity and biofuels. Continued growth of intermittent wind and solar power increases supply, but the planned phase out of Swedish nuclear power will pose challenges to the reliability of the electricity system in the Nordic countries. Bottlenecks in the transmission and distribution grids may restrict a potential growth of electricity use in urban areas, limit new intermittent supply, peak electricity import and export. Environmental concerns may limit growth of biomass use. Local authorities are committed in contributing to national goals on mitigating climate change, while considering their own objectives for economic development, increased energy self-sufficiency and affordable energy costs. Given these circumstances, this thesis investigates existing technical and economic potentials of renewable energy (RE) resources in the Nordic countries with a focus on the northern counties of Finland, Norway and Sweden. The research further aims to provide sets of optimal solutions for sustainable Nordic municipal energy systems, where the interaction between major energy sectors are studied, considering multiple objectives of minimizing annual energy system costs and reducing carbon emissions as well as analyzing impacts on peak electricity import and export. This research formulates an integrated municipal energy system as a multi-objective optimization problem (MOOP), which is solved by interfacing the energy system simulation tool EnergyPLAN with a multi-objective evolutionary algorithm (MOEA) implemented in Matlab. In a first step, the integration or coupling of electricity and heating sectors is studied, and in a second step, the study inquires the impacts of an increasingly decarbonized transport sector on the energy system. Sensitivity analysis on key economic parameters and on different grid emission factors is performed. Piteå (Norrbotten County, Sweden) is a typical Nordic municipality, which serves as a case study for this research. The research concludes that significant techno-economic potentials exist for the investigated resources. Optimization results show that CO2 emissions of a Nordic municipal energy system can be reduced by about 60% without a considerable increase in total energy system costs and that peak electricity import can be reduced by up to 38%. The outlook onto 2030 shows that the transport sector could be composed of high electrification shares and biofuels. Technology choices for optimal solutions are highly sensitive to electricity prices, discount rates and grid emission factors. The inquiries of this research provide important insights about carbon mitigation strategies for integrated energy sectors within a perspective on Nordic municipalities. Future work will refine the transport model, develop and apply a framework for multi-criteria decision analysis (MCDA) enabling local decision makers to determine a technically and economically sound pathway based on the optimal alternatives provided, and analyze the existing policy framework affecting energy planning of local authorities.
Kommunala energisystem i nordiska miljöer möter flera utmaningar: det kalla klimatet, storskaliga industrier, en stor andel elvärme och långa distanser driver energiförbrukningen. Medan åtgärder vidtas på efterfrågesidan för att minimera energianvändningen, kan utsläppsminskande åtgärder inom gruvdrift, industrier, uppvärmningen och transportsektorn öka förbrukningen av el och biobränslen. Fortsatt tillväxt av intermittent vind- och solkraft ökar elproduktion, men den planerade avvecklingen av svensk kärnkraft kommer att utmana tillförlitligheten i elsystemet i de nordiska länderna. Flaskhalsar i överförings- och distributionsnäten kan begränsa en potentiell tillväxt av elanvändningen i stadsområden, begränsa ny intermittent utbud, och påverka elutbyte mellan länderna. Miljöhänsyn kan begränsa ökad användning av biomassa. Lokala myndigheter är engagerade i att bidra till nationella klimatmål, samtidigt som de följer sina egna mål för ekonomisk utveckling, ökad självförsörjning av energi och överkomliga energikostnader. Mot bakgrund av dessa omständigheter undersöker denna avhandling befintliga tekniska och ekonomiska potentialer för förnybar energi i Norden med fokus på de nordliga länen i Finland, Norge och Sverige. Forskningen syftar vidare till att utveckla optimala lösningar för hållbara nordiska kommunala energisystem, där samspelet mellan stora energisektorer studeras, med tanke på att minimera årliga energisystemkostnader och samtidigt minska koldioxidutsläppen samt analysera påverkan på elimport till och export från kommunen. Denna forskning formulerar ett integrerad kommunalt energisystem som multimåloptimeringsproblem (multi-objective optimisation problem - MOOP), som löses genom att kombinera simuleringsverktyget EnergyPLAN med en evolutionär algoritm implementerad i Matlab. I ett första steg studeras kopplingen av el- och värmesektorerna, och i ett andra steg effekterna av en integrerad och alltmer förnybar transportsektor på energisystemet. Känslighetsanalys på viktiga ekonomiska parametrar och på olika utsläppsfaktorer utförs. Piteå (Norrbottens län, Sverige) är en typisk nordisk kommun som fungerar som en fallstudie för detta arbete. Forskningens slutsatser innebär att det finns betydande teknisk-ekonomiska potentialer för de undersökta förnybara resurserna. Optimeringsresultaten visar att koldioxidutsläppen från ett nordiskt kommunalt energisystem kan minskas med cirka 60% utan en avsevärd ökning av de totala energisystemkostnaderna och att den högsta elimporten kan minskas med upp till 38%. Resultat för år 2030 visar att transportsektorn kan ha en mycket hög elektrifieringsgrad och samtidigt används biobränslen i tunga fordon. Optimala lösningar är mycket känsliga för elpriser, räntor och utsläppsfaktorer. Detta arbete ger viktiga insikter om strategier för koldioxidminskning för integrerade energisektorer i ett perspektiv på nordiska kommuner. Min framtida forskning kommer att förfina transportmodellen, utveckla och tillämpa ett ramverk för beslutsanalys med flera kriterier (multi-criteria decision analysis - MCDA) som ska stödja lokala myndigheter att fastställa tekniskt och ekonomiskt hållbara lösningar i deras energiplanering.
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14

Shirvani, Tara. "The role of catalysts and algae in forming a sustainable solution for a global food and fuel crisis." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:30af0957-1ed6-4ea7-949b-f120606ab22e.

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This thesis undertakes three separate lifecycle analyses to determine the emissions and fossil energy demand required to process algae biomass into renewable fuel and animal feed. A complete well-to-wheel fuel-cycle analysis is conducted for the production of biodiesel and jet biofuel from algae biomass. The environmental impacts of algae-based fuels for the road transportation and aviation industry are benchmarked against analogue conventional fossil fuels. This thesis demonstrates that algae biofuel production can only realize its inherent environmental advantage of reduced GHG emissions, once every step of the production chain is fully optimized and decarbonized. This includes smart co-product utilization, offsetting fertilizers through wastewater recycling, reusing exhaust gases as additional CO2 source and using decarbonized electricity, heat and indirect energy. The definition of a Catalyst Sensitivity Index (CSI) demonstrates how catalytic efficiency increases can impact the fossil energy consumption and the greenhouse gas emissions balance of catalyst-dependent processes. The CSI will allow the industry to highlight 'best practice catalysts' and draw conclusions for what efficiency gains one could anticipate with higher performance catalysts. For countries where a decarbonized electricity and heat grid is not available to guarantee low-carbon algae fuel production and the looming resource scarcity around marine feed production has become more pressing, the alternative use of algae for aquafeed production is recommended. This thesis analyses major routes towards the future cost-competitive production of microbial biomass as sustainable fish meal and oil source to meet a global demand for depleting fish feed supplies. A comprehensive economic cost analysis and lifecycle assessment demonstrates the feasibility of replacing global fish meal and fish oil supplies with low-carbon and affordable algae feed by the year 2030. This research reveals how algae feed production has the potential to transform a pressing resource tipping point into a turning point.
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15

Nilsson, Daniel. "Analysis and simulation of systems for delivery of fuel straw to district heating plants /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5721-1.pdf.

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16

Rodrigues, Sérgio Bezerra de Menezes. "Avaliação das alternativas de transporte de etanol para exportação na região Centro-Sul." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-07042008-114034/.

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O etanol, produto proveniente da indústria sucroalcooleira, um dos setores mais importantes da economia brasileira, atrai a atenção dos países desenvolvidos. O aumento de sua demanda em todo o mundo, motivado por razões econômicas e ambientais, impulsiona sua exportação. O volume exportado passou de 750 milhões de litros em 2003 para 3,5 bilhões de litros em 2006 e os produtores estimam que em cinco anos este volume alcance 6,5 bilhões de litros. Diante da perspectiva de acréscimo nas exportações, e do fato de quase 90% da produção brasileira concentra-se no Centro-Sul, esta dissertação tem por objetivo analisar as alternativas de transporte de etanol para exportação no médio prazo, baseado no plano de investimentos proposto pelo projeto do corredor de exportação de etanol da Transpetro, um dos investimentos propostos para melhorar a eficiência logística do transporte de etanol. Tais investimentos pretendem atender a demanda instalada pelo mercado internacional de forma satisfatória, garantindo o suprimento do combustível e prevenindo o surgimento de gargalos logísticos motivados por falta de infra-estrutura suficiente para o escoamento da produção. Foram avaliadas três alternativas de transporte que representam a movimentação de etanol das unidades produtoras aos portos: alternativa rodoviária, alternativa rodo-dutoviária, e alternativa rodo-hidro-dutoviária. Definidas as alternativas, foram identificadas as trinta principais zonas produtoras de etanol e analisadas as alternativas específicas para cada uma. Assim, foi possível identificar as principais vantagens competitivas das alternativas de transporte por região produtora e verificar os ganhos derivados do transporte por dutos e pela hidrovia no escoamento da produção de etanol até os principais portos.
Ethanol, a product originated from the sugarcane and ethanol industry, one of the most important sectors in the brazilian economy is attracting the interest of the developed countries. The exportation of ethanol is stimulated by the increasing worldwide demand driven by economic and environmental reasons. The exported volume increased from more than 750 million liters in 2003 to 3.5 billion liters in 2006 and, in the next five years, the brazilian producers expect that this volume will reach 6.5 billion liters. Because of this expectation in increasing exportations of ethanol, and being aware that the center-south region of Brazil produces almost 90% of the brazilian ethanol, the objective of this dissertation is to analyze the alternatives of transportation of ethanol for exportation in the medium term. This study is based in the Transpetro´s corridor of ethanol exportation investment plan, which is one of the proposed investments to increase the logistic efficiency of the transportation of ethanol. These investments intend to satisfactorily fulfill the demand of the international market, guaranteeing the supply of ethanol and preventing the appearance of logistic gaps due to lacks of infra-structure for transporting the product. Three alternatives of transportation were evaluated, representing the transportation of ethanol from the manufacturing units to the ports: roadway alternative, road-pipeline alternative and road-waterway-pipeline alternative. After the definition of these alternatives, the thirty major manufacturing zones of ethanol were defined and each zone had these alternatives analyzed. As a result, the major competitive advantages of the transportation alternatives by zone were identified. Also, the potential gains of transporting ethanol to the major seaports by pipelines and waterways were evaluated.
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17

Nicol, Christopher. "Understanding the innovation process towards the development of a biofuel transport system /." Umeå : Umeå School of Business, Umeå University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22884.

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18

Jambo, Moono. "Illustrative scenarios of biofuel policiesfor transport sector in a developingcountry; A case study of Zambia." Thesis, KTH, Energiteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101485.

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The increasing demand for transportion fuels has led most countries around the world to look for alternatives to the predominant fossil fuels in the sector. Furthermore, the needs for security of energy supply, social – economic and sustainable development are among the factors driving the search for alternative fuels with regard to the fact that most oil producing countries are politically unstable. Developing countries are not an exception and are also formulating policies that will enhance development of alternatives to fossil fuels.   This study analyses the opportunities and consequences of the development of the biofuels industry in Zambia from a local, regional and global perspective with regard to policy, technical, socio – economic, environment and sustainability considerations. From analysis of global, regional and local situation, the development of biofuels in Zambia is simulated using Long – range Energy Alternatives Planning system (LEAP) under different policy assumptions with consideration of current and future demands. Furthermore, the socio – economic and environmental consequences are modelled in LEAP using these policies and other assumptions which include demand – cost projections. The environmental loadings are also simulated for the period with the assumption that biofuels are zero net emitters of green house gases. Land requirements are then estimated from these results for the simulated period. A model of illustrative scenarios for implementation of different biofuels policies is developed which can be used to monitor and analyse their consequences by adjusting the major parameters depending on varying circumstances.   The results of this study show that there is considerable potential for feedstock, land, water and mature technology for production of both biodiesel and bioethanol to meet blending demands for the simulated period. There is considerable potential for production of bioethanol from sugar cane and sweet sorghum using the well established fermentation processes. Biodiesel can be produced from jatropha and other oil bearing plants. Most of the current fleet of vehicles in Zambia was manufactured after 1990, thus there is little or no modification required on engines to run on low biofuel blends considered in the simulations. It is clear from the results of the simulation that biofuel demand for blends of 5% in 2015 rising to 10% in 2030 with current yields required for both can be achieved with the available land ad water resources. To achieve the 10% blending target set in the simulated period for bioethanol and biodiesel from sugar cane and jatropha, land required is 4,480Ha and 47,000Ha respectivey for growing this feedstock at current yields for the region. The GHG reduction would be equivalent to the 10% in 2030 if we assume that biofuels are zero net emitters. However, policies have to be formulated and implemented which should include manadatory blending targets and incentives on tax and investments.
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Aaman, Sophia, and Lundberg Johan Henrik Hessel. "Setting the seeds for a green growth -A Study of biofuel development in Indonesia’s transport sector." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-219906.

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Moktan, Uttam. "Biofueled Public Transport for sustainable transportation: A case study of Stockholm and possibility in Kathmandu." Thesis, Stockholms universitet, Kulturgeografiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-92321.

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Uttam Moktan, Biofueled Public Transport for sustainable transportation: Case Study of Stockholm and possibility in KathmanduHuman Geography, advanced level, master thesis for master exam in Geography, 30 ECTS creditsSupervisor: Lennart TonellLanguage: EnglishDue to the hotly debated issues of global warming and climate change, the world is constantly looking for a replacement for fossil fuels which have less impact on the environment. Biofuels in recent years has been considered a great solution to this problem. The transport sector has been experimented with these biofuels and Sweden is one of the leading nations in using biofuels in transportation sector. The purpose of this study was to study if the Stockholm‟s Biofueled public transportation has been able to meet its objectives of sustainable transportation and what lessons can a third world city like Kathmandu learn from the experience of Stockholm‟s biofueled public transportation. Semi-structured interviews were used to collect information from the stakeholders both in Stockholm and Kathmandu. The study showed the importance of tax exemption policy and government support for the biofuels industry. Kathmandu can learn to develop a democratic and accountable public transportation system for a sustainable transportation. Study showed that biofuels promotion is a complicated process and needs lots of social and infrastructural changes. Kathmandu needs to develop an effective tax policies, technological experimentation, social awareness and investment. Kathmandu is not in the position of promoting biofuels itself. So, donor assistance can be a great support to promote biofuels in public transportation in Kathmandu and other third world cities to globally reduce the effect of climate change.Key Words: climate change, biofuels, public transportation, sustainable transportation, tax exemption, Stockholm, Kathmandu
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Jenkins, Rhodri. "Renewable liquid transport fuels from microbes and waste resources." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655722.

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In order to satisfy the global requirement for transport fuel sustainably, renewable liquid biofuels must be developed. Currently, two biofuels dominate the market; bioethanol for spark ignition and biodiesel for compression ignition engines. However, both fuels exhibit technical issues such as low energy density, poor low temperature performance and poor stability. In addition, bioethanol and biodiesel sourced from first generation feedstocks use arable land in competition with food production, and can only meet a fraction of the current demand. To address these issues it is vital that biofuels be developed from truly sustainable sources, such as lignocellulosic waste resources, and possess improved physical properties. To improve and control the physical properties of a fuel for specific application, one must be able to tailor the products formed in its production process. All studies within this thesis, therefore, have the aim of assessing the fuels produced for their variability in physical property, or the aim of directing the process considered to specific fuel molecules. In Chapter 2, spent coffee grounds from a range of geographical locations, bean types and brewing processes were assessed as a potential feedstock for biodiesel production. While the lipid yield was comparable to that of conventional biodiesel sources, the fatty acid profile remained constant irrespective of the coffee source. Despite this lack of variation, the fuel properties varied widely, presumably due to a range of alternative biomolecules present in the lipid. Though coffee biodiesel was produced from a waste product, the fuel properties were found to be akin to palm oil biodiesel, with a high viscosity and pour point. The blend level would therefore be restricted. In Chapter 3 the coffee lipid, as well as a range of microbial oils potentially derived from renewable sources were transformed into a novel aviation and road transport fuel through cross-metathesis with ethene. Hoveyda-Grubbs 2nd generation catalyst was found to be the most suitable, achieving 41% terminal bond selectivity under optimum conditions. Metathesis yielded three fractions: an alkene hydrocarbon fraction suitable for aviation, a shorter chain triglyceride fraction that upon transesterification produced a short chain biodiesel fuel, and a multifunctional volatile alkene fraction that could potentially have application in the polymer industry. Though there was variation for the road transport fuel fraction due to the presence of long chain saturates, the compounds fell within the US standard for biodiesel. The aviation fraction lowered the viscosity, increased the energy density, and remained soluble with Jet A-1 down to the required freezing point. Oleaginous organisms generally only produce a maximum of 40% lipid, leaving a large portion of fermentable biomass. In Chapter 4, a variety of ethyl and butyl esters of organic acids – potentially obtainable from fermentation – were assessed for their suitability as fuels in comparison to bioethanol. One product, butyl butyrate, was deemed suitable as a Jet A-1 replacement while four products, diethyl succinate, dibutyl succinate, dibutyl fumarate and dibutyl malonate, were considered as potential blending agents for diesel. Diethyl succinate, being the most economically viable of the four, was chosen for an on-engine test using a 20 vol% blend of DES (DES 20) on a chassis dynamometer under pseudo-steady state conditions. DES20 was found to cause an increase in fuel demand and NOx emissions, and a decrease in exhaust temperature, wheel force, and CO emissions. While fermentation is generally directed to one product, producing unimolecular fuels, they do not convert the entirety of the biomass available. An alternative chemical transformation is pyrolysis. In Chapter 5, zeolite-catalysed fast pyrolysis of a model compound representative of the ketonic portion of biomass pyrolysis vapour – mesityl oxide – was carried out. The aim of this study was to understand the mechanistic changes that occur, which could lead to improved bio-oil yields and more directed fuel properties of the pyrolysis oil. While HZSM-5 and Cu ZSM-5 showed no activity for hydrogenation and little activity for oligomerisation, Pd ZSM-5 led to near-complete selective hydrogenation of mesityl oxide to methyl isobutyl ketone, though this reduced at higher temperatures. At lower temperature (150-250 °C), a small amount of useful oligomerisation was observed, which could potentially lead to a selective pyrolysis oligomerisation reaction pathway.
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Galbieri, Rodrigo 1977. "O transporte rodoviário de passageiros no Brasil : estratégias de mitigação do consumo energético e da emissão de CO2." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264173.

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Orientador: Andre Felipe Simões
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: O presente Estudo possui como objetivo principal realizar uma análise quantitativa dos impactos sobre o consumo de combustíveis e das emissões de CO2 de medidas de eficiência energética e aumento no uso de biocombustíveis para o setor de transportes rodoviário brasileiro de passageiros (veículos leves, motocicletas e ônibus) - de forma isolada e conjunta - entre os anos 2010 a 2030. Concomitantemente, visa oferecer uma "cesta" de opções para os tomadores de decisões (esferas políticas) para o setor de transportes brasileiro de passageiros nas áreas de eficiência energética, combustíveis alternativos e medidas de gestão da demanda. A citada "cesta" de opções envolve aspectos qualitativos e quantitativos dessas medidas de mitigação. Para se atingir o objetivo proposto realizou-se uma análise do potencial técnico-econômico de tecnologias relacionadas à mitigação do consumo de combustíveis e das emissões de CO2, no horizonte de tempo 2010 a 2030. Já a metodologia utilizada na análise quantitativa estima a frota de veículos circulantes no Brasil, o consumo de combustíveis e as emissões de CO2 do setor de transportes rodoviário de passageiros adotando uma abordagem bottom-up. Adotou-se, como premissa, que o ano de início da implementação das medidas mitigatórios para os Cenários Alternativos seria 2015. Foi criado um Cenário Tendencial (denominado BAU - Business-as-Usual) e mais 3 grupos de cenários alternativos - modelados com diferentes padrões de aumento de eficiência energética e/ou uso de biocombustíveis (etanol anidro, etanol hidratado e biodiesel), incluindo a conversão da frota de ônibus a óleo Diesel para etanol aditivado. De acordo com os resultados apresentados pelas projeções desse Estudo, mantidas as tendências atuais até o ano de 2030, o crescimento projetado das emissões de CO2 no Cenário BAU, entre os anos de 2010 e 2030, foi de expressivos 120%. Contudo, os resultados das simulações, revelam possibilidades de mitigações das emissões de CO2 entre 5% a 48% para o caso dos cenários propostos, em relação ao Cenário BAU. Os resultados do presente Trabalho permitem intuir que as atuais políticas para promoção do uso de biocombustíveis de primeira geração no Brasil, combinadas com programas de eficiência energética veicular, incluindo hibridização, formam uma estratégia robusta de mitigação. Tais estratégias se mostram factíveis às questões envolvendo a problemática e tênue relação entre ("produção" e uso de) energia e meio ambiente, principalmente no que se refere ao uso do solo (desmatamentos e produção de alimentos). Apesar de não ter sido quantificado, em virtude das limitações do modelo escolhido, medidas de gerenciamento da demanda por transporte devem fazer parte das políticas públicas na área de transporte, pois o potencial de mitigação dessas medidas, conforme os exemplos analisados são substanciais
Abstract: The present thesis has, as the mains goal, to provide a quantitative analysis of the impacts on fuel consumption and CO2 emissions of energy efficiency measures and increased use of biofuels for the Brazilian road transport passenger sector (light vehicles, motorcycles and buses) - separately and together - between the years 2010 and 2030. Concomitantly, it aims to provide a "basket" of options to policymakers in the areas of energy efficiency, alternative fuels and demand management measures. The aforementioned "basket" of options involves qualitative and quantitative aspects of these mitigation measures. To achieve the proposed objectives, it was performed an analysis of the technical and economic potential for the mitigation technologies related to fuel consumption and CO2 emissions, considering the timeline from 2010 to 2030. It's opportune to mention that the methodology used in the quantitative analysis estimates the fleet of vehicles circulating in Brazil, fuel consumption and CO2 emissions from the transportation sector by road by adopting a bottom-up approach, as recommended by the Intergovernmental Panel on Climate Change - IPCC The results of this work indicate that current policies for promoting the use of first generation biofuels in Brazil, combined with vehicular energy efficiency programs, including hybridization, form a robust mitigation strategy. Such strategies appeared feasible to issues involving the problematic and tenuous relationship between ("production" and use of) energy and the environment, particularly with regard to land use (deforestation and food production, mainly). Despite not being quantified, due to limitations of the choose model, demand management measures should be part of public policies in the area of transportation. After all, the potential for mitigation measures, such as the analyzed examples, are substantial. In fact, the results of the simulations reveal possibilities of CO2 emission mitigation among 5% to 48% for the case of the proposed sceneries, in relation to the business as usual scenario
Mestrado
Planejamento de Sistemas Energeticos
Doutor em Planejamento de Sistemas Energéticos
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Souto, Silvia Barroso Gomes. "Caracterização e análise da logística de transporte do etanol nas regiões potenciais ao desenvolvimento do setor sucroalcooleiro no Estado do Tocantins." Universidade Federal do Tocantins, 2013. http://hdl.handle.net/11612/544.

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O presente estudo objetivou caracterizar a logística de transporte do Estado do Tocantins, para a distribuição do etanol levando em consideração o modal rodoviário e ferroviário. Para atender a este objetivo, esta pesquisa quanto aos fins foi do tipo descritiva. O procedimento de coleta de dados foi dividido em duas etapas: a primeira etapa consistiu na realização de pesquisa bibliográfica e documental, que deram apoio ao desenvolvimento do referencial teórico e análise dos resultados do trabalho. Na segunda etapa deste trabalho foi realizada a pesquisa de campo, onde foram aplicados questionários junto a profissionais especializados na área e feitas entrevistas a gestores públicos. No que se refere à análise dos dados e interpretação dos resultados realizou-se uma abordagem qualitativa. Os resultados apresentaram enfoque regional, compreendendo a caracterização da logística do modal rodoviário e ferroviário e a caracterização da logística de transporte das regiões potenciais identificadas por Collicchio (2008). Descrevendo os principais parâmetros referentes à produção agroindustrial da cana-de-açúcar e os parâmetros referentes à logística de transporte de etanol. Concluiu-se que o modal rodoviário é o mais utilizado para a movimentação da logística do setor agrícola em estudo, no entanto, o sistema ferroviário depois de concluído será um importante modal para o transporte de etanol no Tocantins. A caracterização da logística se mostrou importante instrumento para conhecer a região em estudo e para identificar quais os fatores que interferem na logística local, possibilitando ações de melhoria. Espera-se que os estudos na área da logística do setor sucroalcooleiro para produção de etanol ainda possam viabilizar muitas melhorias ao sistema como um todo, minimizando os custos logísticos e contribuindo para o desenvolvimento do setor.
The present study aimed to characterize the transport logistics of the State of Tocantins, for the distribution of ethanol taking into account the modals road and rail. To meet this goal, this research as the purpose was descriptive. The procedure for data collection was divided into two stages: the first stage consisted of literature and documents, which have supported the development of the theoretical analysis and the results of the work. In the second stage of this work was carried out field research where questionnaires were administered with professionals specialized in the area and made interviews with public managers. As regards the analysis of data and interpretation of the results was carried out a qualitative approach. The results showed regional focus, including the characterization of logistics modal road and rail and the characterization of the transport logistics of the potential regions identified by Collicchio (2008). Describing the main parameters for agroindustrial production of cane sugar and the parameters related to the logistics of transporting ethanol. It was concluded that road transport is the most used for handling the logistics of the agricultural sector in the study, however, the rail system will be completed after a major modal to transport ethanol in Tocantins. The characterization of the logistics proved important tool to explore the region under study and to identify the factors that affect the local logistics, enabling improvement actions. It is hoped that studies in logistics sector sugarcane for ethanol production may still facilitate many improvements to the system as a whole, minimizing logistics costs and contributing to the development of the sector.
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Nicola, Andrea Oliveira. "Avaliação econômica e energética de alternativas de transportes do etanol destinado à exportação na região Centro-Sul." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-11022015-085803/.

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O crescente interesse por fontes alternativas de energia, sobretudo por aquelas que consigam mitigar as emissões de gases causadores do efeito estufa (GEE), tem feito com que a produção de biocombustíveis aumentasse significativamente. Neste cenário o etanol produzido a partir da cana de açúcar, tem apresentado vantagem em relação a outros biocombustíveis, uma vez que a energia produzida é relativamente alta quando comparada com a consumida em seu processo produtivo. Neste contexto, as exportações brasileiras, principalmente as da região Centro-Sul, tentam suprir as necessidades mundiais através da produção excedente de etanol no país. No entanto, há gargalos logísticos na distribuição deste produto e isso tem feito que o transporte rodoviário fosse excessivamente utilizado na movimentação do etanol desde a usina até o porto. Diante destes aspectos, esta pesquisa busca investigar alternativas intermodais para a movimentação do etanol destinado à exportação, considerando a viabilidade econômica e energética empregada na cadeia logística deste biocombustível. Para isso, foram gerados quatro cenários utilizando os modos rodoviário, ferroviário, dutoviário e hidroviário. Através dos resultados obtidos, o cenário rodo-ferroviário apresentou uma estimativa de custo da ordem de R$ 654 milhões, valor da mesma ordem de grandeza do cenário rodoviário de referência, que foi de R$ 653 milhões. Já os cenários rodo-dutoviário e rodo-hidro-dutoviário, apresentaram custos maiores, respectivamente da ordem de R$ 661 milhões e R$ 674 milhões respectivamente. Em contrapartida, na análise de mínimo consumo energético o cenário rodo-hidro-dutoviário apresentou um gasto de energia da ordem de 533 mil MJ, cerca de 60% a menos que o consumido no cenário rodoviário, estimado em 1,45 milhões de MJ. Para o cenário rodo-dutoviário obteve-se uma estimativa de 680 mil MJ e para o cenário rodo-ferroviário de 764 mil MJ. Em relação ao porto de destino, São Sebastião foi o que apresentou sistematicamente, a melhor opção para quase todos os cenários analisados.
The growing interest in alternative energy sources, especially for those who can mitigate the emissions of gases causing the greenhouse gases (GHG), has made the production of biofuels increased significantly. In this scenario the ethanol produced from cane sugar, has shown advantages over other biofuels, since the energy generated is relatively high when compared with the consumed in the production process. In this context, brazilian exports, especially the South-Central region, try to supply the global requirements through ethanol production surplus in the country. However, there are logistical bottlenecks in the distribution of this product and it has done that the road transport were excessively used in the ethanol transportation from the plant to the port. Considering these aspects, this research seeks to investigate alternatives to the intermodal transportation of ethanol for export, considering the economic viability and energy used in this biofuel chain logistics. For this, four scenarios were generated using road, rail, pipeline and waterway modes. From the results obtained, the road-rail scenario presented an estimated cost of R$ 654 million, the same order of magnitude of road reference scenario, which was R$ 653 million. Already, the scenarios road-pipeline and road-hydro-pipeline, had higher costs respectively in the order of R$ 661 million and R$ 674 million respectively. In contrast, the analysis of minimum energy consumption the road-hydro-pipeline scenario presented an energy expenditure of approximately 533 thousand MJ, about 60% unless consumed in road scenario, estimated at 1.45 million MJ. For road-pipeline scenario yielded an estimate of 680 thousand MJ and the road-rail scenario of 764 thousand MJ. In relation to the port of destination, São Sebastião was systematically presented, the best option for almost all scenarios analyzed.
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Lindfeldt, Erik G. "A trinity of sense : Using biomass in the transport sector for climate change mitigation." Doctoral thesis, KTH, Energiprocesser, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9292.

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This thesis analyses two strategies for decreasing anthropogenic carbon dioxide (CO2) emissions: to capture and store CO2, and to increase the use of biomass. First, two concepts for CO2 capture with low capture penalties are evaluated. The concepts are an integrated gasification combined cycle where the oxygen is supplied by a membrane reactor, and a hybrid cycle where the CO2 is captured at elevated pressure. Although the cycles have comparatively high efficiencies and low penalties, they illustrate the inevitable fact that capturing CO2 will always induce significant efficiency penalties. Other strategies are also needed if CO2 emissions are to be forcefully decreased. An alternative is increased use of biomass, which partially could be used for production of motor fuels (biofuels). This work examines arguments for directing biomass to the transport sector, analyses how biofuels (and also some other means) may be used to reduce CO2 emissions and increase security of motor fuel supply. The thesis also explores the possibility of reducing CO2 emissions by comparatively easy and cost-efficient CO2 capture from concentrated CO2 streams available in some types of biofuel plants. Many conclusions of the thesis could be associated with either of three meanings of the word sense: First, there is reason in biofuel production – since it e.g. reduces oil dependence. From a climate change mitigation perspective, however, motor fuel production is often a CO2-inefficient use of biomass, but the thesis explores how biofuels’ climate change mitigation effects may be increased by introducing low-cost CO2 capture. Second, the Swedish promotion of biofuels appears to have been governed more by a feeling for attaining other goals than striving for curbing climate change. Third, it seems to have been the prevalent opinion among politicians that the advantages of biofuels – among them their climate change mitigation benefits – are far greater than the disadvantages and that they should be promoted. Another conclusion of the thesis is that biofuels alone are not enough to drastically decrease transport CO2 emissions; a variety of measures are needed such as fuels from renewable electricity and improvements of vehicle fuel economy.
QC 20100823
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Nordhammer, Caroline, and Amanda Stenberg. "Etanol som drivmedel : En analys av etanolbränslets minskade användning och dess framtidsutsikter." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-253896.

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The use of biofuels within the Swedish transport sector has increased, although the use of ethanolhas decreased considerably since 2011. The purpose of this report is to examine why and onwhat grounds this decrease has occurred. Furthermore the report aims to discuss whether thisdevelopment is beneficial to reaching the climate goals of Sweden. The study focuses solely onethanol as a high proportion blend of E85 for road transportation and its future within theSwedish transport sector. The following questions have therefore been formulated: Why has thesale of ethanol (E85) decreased? Can ethanol (E85) be a tool for Sweden in order to reach itsclimate goals? In order to answer these questions, 12 interviews were conducted with different stakeholdersrelated to ethanol fuel. Stakeholders represented in this report are: organizations, authorities, fueldistributors, car manufacturers, scientists and purchasers. From the interviews, a number offactors that are assumed to have impacted the use of E85 were identified. The identified factorswere: the debate around the land use for ethanol production and its connection to increased foodprices and climate benefit, technical problems, increased operating costs, political means ofcontrol and pricing, and limited sales of new cars. It is probable that no single factor caused thedecrease in the use of E85, but that it was rather a combination of all of the aforementionedfactors over a certain period of time that lead to the decrease. In order for Sweden to reach its climate goals, three factors are significant: energy efficiency, adecrease in transportation and increased usage of renewable fuels must be implemented. E85could be part of the solution in order to reach these goals. There currently exists an infrastructurefor E85, which means that the goals can be reached in the short term, compared to electrification,which is considered to be a long term solution. Political means of control are crucial to the roleof the biofuel in the transition that is required to reach the goals, since they decide how E85 willbe able to compete on the fuel market going forward.
Användningen av biodrivmedel inom den svenska transportsektorn har ökat, däremot haretanolanvändningen minskat kraftigt sedan 2011. Syftet med denna rapport är att undersökavarför och på vilka grunder denna minskning har skett. Därutöver ämnar även rapporten attredogöra för en diskussion kring huruvida denna utveckling är gynnsam för att nå Sverigesuppsatta klimatmål eller inte. Studien avser endast att studera etanol som höginblandning i E85för vägtransporter och dess framtid inom den svenska transportsektorn. Följande frågeställningarhar formulerats: Varför har försäljningen av etanol (E85) som drivmedel minskat? Kan etanol(E85) utgöra ett medel för att Sverige ska nå sina uppsatta klimatmål? För att besvara frågeställningarna genomfördes 12 intervjuer med olika aktörstyper som ärrelaterade till etanolbränsle. Aktörstyper som representeras i denna rapport är:intresseorganisationer, myndigheter, drivmedelsdistributörer, biltillverkare, forskare samtupphandlare. Utifrån intervjuerna identifierades faktorer som antas ha påverkat användningen avE85. De faktorer som identifierades var: debatten kring etanolproduktionens markanvändningoch dess koppling till höjda livsmedelspriser samt klimatnytta, tekniska problem, högredriftkostnader, politiska styrmedel och prisbildning samt begränsad nybilsförsäljning. Det ärsannolikt att det inte var en enskild faktor som gav upphov till minskningen utan att det iställetrörde sig om en kombination av samtliga påverkansfaktorer under en viss tidsperiod. För att Sverige ska kunna nå landets klimatpolitiska mål är en förutsättning att det sker enenergieffektivisering, en minskning av transporter samt en ökad användning av förnybaradrivmedel. E85 kan utgöra en del av lösningen för att nå målen. Idag finns en tillgängliginfrastruktur för E85 vilket medför att målen kan nås på kort sikt i jämförelse med enelektrifiering som anses vara en långsiktig lösning. Politiska styrmedel är avgörande förbiobränslets roll i omställningen som krävs för att nå målen. Detta eftersom dessa avgör hur E85kommer att kunna konkurrera på marknaden för drivmedel fortsättningsvis.
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Molnar, Istvan, David Lopez, Jennifer Wisecaver, Timothy Devarenne, Taylor Weiss, Matteo Pellegrini, and Jeremiah Hackett. "Bio-crude transcriptomics: Gene discovery and metabolic network reconstruction for the biosynthesis of the terpenome of the hydrocarbon oil-producing green alga, Botryococcus braunii race B (Showa)*." BioMed Central, 2012. http://hdl.handle.net/10150/610020.

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BACKGROUND:Microalgae hold promise for yielding a biofuel feedstock that is sustainable, carbon-neutral, distributed, and only minimally disruptive for the production of food and feed by traditional agriculture. Amongst oleaginous eukaryotic algae, the B race of Botryococcus braunii is unique in that it produces large amounts of liquid hydrocarbons of terpenoid origin. These are comparable to fossil crude oil, and are sequestered outside the cells in a communal extracellular polymeric matrix material. Biosynthetic engineering of terpenoid bio-crude production requires identification of genes and reconstruction of metabolic pathways responsible for production of both hydrocarbons and other metabolites of the alga that compete for photosynthetic carbon and energy.RESULTS:A de novo assembly of 1,334,609 next-generation pyrosequencing reads form the Showa strain of the B race of B. braunii yielded a transcriptomic database of 46,422 contigs with an average length of 756 bp. Contigs were annotated with pathway, ontology, and protein domain identifiers. Manual curation allowed the reconstruction of pathways that produce terpenoid liquid hydrocarbons from primary metabolites, and pathways that divert photosynthetic carbon into tetraterpenoid carotenoids, diterpenoids, and the prenyl chains of meroterpenoid quinones and chlorophyll. Inventories of machine-assembled contigs are also presented for reconstructed pathways for the biosynthesis of competing storage compounds including triacylglycerol and starch. Regeneration of S-adenosylmethionine, and the extracellular localization of the hydrocarbon oils by active transport and possibly autophagy are also investigated.CONCLUSIONS:The construction of an annotated transcriptomic database, publicly available in a web-based data depository and annotation tool, provides a foundation for metabolic pathway and network reconstruction, and facilitates further omics studies in the absence of a genome sequence for the Showa strain of B. braunii, race B. Further, the transcriptome database empowers future biosynthetic engineering approaches for strain improvement and the transfer of desirable traits to heterologous hosts.
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Žaglinskis, Justas. "Dyzelinių variklių, dirbančių antros kartos biodegalų mišiniais,eksploatacinių charakteristikų tyrimai." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20141217_125818-22450.

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Disertacijos tyrimų aktualumą lemia energijos panaudojimo efektyvumo didinimas bei aplinkos taršos mažinimas transporto sektoriuje. Darbe sprendžiami eksperimentiniai, matematinio modeliavimo ir metodologiniai uždaviniai, siekiant kompleksiškai ištirti dyzelinių variklių, dirbančių II kartos RRME, alkoholio ir dyzelino mišiniais, eksploatacinius darbo rodiklius. Disertacijoje analizuotas ir įvertintas degalų mišinių panaudojimo lengvųjų automobilių ir pagalbiniame laivo dyzeliniuose varikliuose efektas. Tiriamojo darbo problematika, tikslas, uždaviniai suformuoti išanalizavus transporto sektoriaus sandarą, svarbą oro taršos ir energijos sunaudojimo srityse bei ES strateginius planus. Laboratorijos bei eksploatacijos sąlygomis ištirti I, II kartos biodegalų ir dyzelino mišiniai. Tyrimams panaudotuose varikliuose išbandyti butanolio ir metanolio su rapso metil/butilesteriais bei dyzelino 2 ir 3 komponentų mišiniai. Išbandyti II kartos RRME mišiniai: Sėjamosios judros (lot. Camelina sativa) kartu su kiaulienos RRME ir mikro dumblių (lot. Clorella sp.). Atlikti dyzelino ir mišinių palyginamieji variklinių savybių tyrimai. Panaudojant mišinius, energijos panaudojimo efektyvumas didėja ~1–4 %; esant šiek tiek išaugusiai NOX koncentracijai, CO, CH koncentracijos sumažėjimas siekia iki 20 %, o deginių dūmingumas – 55–85 %. Įvertinti terminės ir mechaninės apkrovos kriterijai, indikuojantys variklio konstrukcinį patikimumą dirbant dyzelinu ir degalų mišiniais. Ištirta biodyzelinų... [toliau žr. visą tekstą]
The relevance of dissertation research is determined increasing efficiency of energy use and reduction of environmental pollution in the transport sector. In order to accomplish the complex research of diesel engines (running on 2nd generation FAME, alcohol and diesel blends) performance indicators the experimental, simulation and methodological tasks are solved in dissertation. The analysis and evaluation of effect of fuel blends use in passenger car and vessel auxiliary diesel engines is presented in dissertation. The problem, aim, tasks of research work formulated after analysis of transport sector structure, the importance of air pollution and energy consumption and the EU's strategic plans. The blends of 1st and 2nd generation biofuels were investigated using laboratory equipment and in the exploitation conditions. 2 and 3 component blends of diesel, methanol, butanol, rape methyl/butyl esters were tested in diesel engines. Tested 2nd generation FAME blends: False flax (lat. Camelina sativa) with pork lards FAME and sea algae (lat. Clorella sp.). The comparable research of parameters while engine ran on diesel and blends was carried out. In the case of blends use the energy efficiency increases ~1–4%; at slightly increased NOX concentration the CO and CH concentrations decreased up to 20% and exhaust smoke, and smokiness decreased – 55–85%. The evaluation of thermal and mechanical load criteria which indicate 1.9 TDI 1Z engine reliability operating on diesel fuel and... [to full text]
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Silva, Bruno Tiago Angelo da. "UtilizaÃÃo de Materiais Alternativos para a ConstruÃÃo de Pavimentos Urbanos na RegiÃo Metropolitana de Fortaleza." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7788.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
A escassez de matÃria-prima natural nos grandes centros urbanos incentiva o estudo de materiais alternativos. No que diz respeito à geraÃÃo de resÃduos da construÃÃo e demoliÃÃo (RCD), a problemÃtica ultrapassa as barreiras econÃmicas e a sua disposiÃÃo irregular resulta em transtornos à populaÃÃo das formas mais diversas: proliferaÃÃo de vetores de doenÃas, enchentes, obstruÃÃo de vias, dentre outras. Pesquisas realizadas no exterior e no Brasil mostram a possibilidade de reaproveitamento destes resÃduos na Ãrea de pavimentaÃÃo. No Brasil, jà existem trechos de rodovias executados com a aplicaÃÃo do RCD como agregado. No estado do CearÃ, na Ãrea da RegiÃo Metropolitana de Fortaleza (RMF), foco desta pesquisa, dois solos foram estudados: um arenoso e um argiloso. Esses solos foram estabilizados granulometricamente com um RCD puro, de dimensÃes graÃdas, em trÃs taxas distintas (40%, 50% e 60% de agregado reciclado). As anÃlises de laboratÃrio envolveram ensaios de caracterizaÃÃo, ambientais, ensaios mecÃnicos de resistÃncia e anÃlise da imprimaÃÃo betuminosa. No que diz respeito à imprimaÃÃo betuminosa, o estado do Cearà utiliza, predominantemente, o asfalto diluÃdo de cura mÃdia (CM-30) Os asfaltos diluÃdos tÃm sua utilizaÃÃo questionada em diversos paÃses que possuem uma legislaÃÃo ambiental mais rÃgida, devido à utilizaÃÃo do querosene como diluente. Este derivado do petrÃleo libera volÃteis e atinge os lenÃÃis freÃticos, causando danos ambientais. Tendo por base este pressuposto, a pesquisa propÃs a substituiÃÃo do diluente convencional pelo biodiesel de soja, em uma composiÃÃo de um asfalto diluÃdo denominada CAP/BIO. O biodiesel à um biocombustÃvel, produzido a partir de Ãleos vegetais, gordura animal e Ãleos residuais, que possui, entÃo, uma grande versatilidade no que diz respeito à sua produÃÃo. Este trabalho avalia o comportamento da imprimaÃÃo betuminosa em corpos de prova simulando bases granulares constituÃdas de solos estabilizados com RCD a partir da utilizaÃÃo dos dois ligantes supracitados (CM-30 e CAP/BIO) em trÃs taxas distintas (0,8 L/mÂ; 1,0 L/mÂ; 1,2 L/mÂ). Os corpos de prova foram preparados para diferentes misturas de RCD nos teores de umidade de compactaÃÃo. Os resultados experimentais mostraram que tanto a estabilizaÃÃo dos solos da RMF com RCD, como o material testado (CAP/BIO) podem ser alternativas viÃveis a serem aplicadas na Ãrea de pavimentaÃÃo. Os resultados apresentaram valores satisfatÃrios em praticamente todos os cenÃrios, sendo as misturas de solo com adiÃÃo de 50% de RCD as mais indicadas, para ambos os solos, moldadas à energia inter-modificada de compactaÃÃo.
The shortage of natural raw materials in large urban centers encourages the study of alternative materials. With regard to the generation of waste from construction and demolition waste (CDW) the problem goes beyond the economic barriers and their irregular arrangement results in disturbances to the population in many different ways: proliferation of vectors, flooding, obstruction of roads, among others. Several researches we carried out abroad and in Brazil to show the possibility of reuse of waste in the pavement area. In Brazil, there are stretches of road running with the application of the RCD as an aggregate. The state of CearÃ, in the Fortaleza Metropolitan Region (RMF), researchâs focus, have two poor soils, a sandy and a clay, granulometric stabilized with RCD pure, at three different rates (40 %, 50% and 60% of recycled aggregate). The experimental program includes characterization tests, environmental tests and mechanical resistance. Allied to this, there is a perceived need to decrease the environmental impacts of paving works around the world. In the case of bituminous primer, the state of Cearà uses predominantly asphalt diluted medium-cure (CM-30) The diluted asphalt have its use questioned in several countries with rigid environmental legislation due to use of kerosene as diluent. This petroleum-derived compound causes untold environmental damages. Based on this assumption, the research proposes to replace the conventional solvent by biodiesel, resulting in a composition of asphalt diluted called CAP/BIO. It should be noted that biodiesel is a biofuel produced from vegetable oils, animal fats and waste oils, with a great versatility with regard to their production. This study evaluates the behavior of bituminous primer on specimens simulating bases consisting of granular soils and CDW, with the use CM-30 and CAP/BIO at three different rates (0.8 L/mÂ; 1.0 L/mÂ, 1.2 L/mÂ). The experimental results showed that both the stabilization of the soil in RMF with CDW and the material tested (CAP/BIO) can be interesting alternative materials to be used, but only if the peculiarities and eccentricities of each material were respected.
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30

Millinger, Markus. "Systems assessment of biofuels: Modelling of future cost and greenhouse gas abatement competitiveness between biofuels for transport on the case of Germany." 2017. https://ul.qucosa.de/id/qucosa%3A33246.

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Biofuels are a renewable alternative for reducing the climate impact of transport. Due to the versatility of biomass and complexity of economics and impacts, biofuels are part of a complex system, which is here analysed from a systems perspective. Several models are developed in order to assess the competitiveness of various crop based biofuel options as part of a system, using different economic and environmental functional units. The scope is set to Germany until 2050. The capital and feedstock costs were revised to higher levels compared to common assumptions. The different functional units result in different merit orders for the biofuel options. Currently used biofuels, rape seed based biodiesel and starch crop based bioethanol, were found not to be competitive when considering differentiated and increasing feedstock costs. Advanced liquid fuels were only competitive at extreme assumptions, contrary to common expectations. Instead, sugar beet based ethanol dominated for most of the time span when comparing energetic cost, whereas Synthetic Natural Gas (SNG) was competitive on a greenhouse gas abatement (GHG) cost basis, especially at a rapid decarbonisation of the power mix. With a land use GHG abatement functional unit, silage maize based biomethane was the best, with SNG converging only at very high renewables shares of the background systems. Switching from current practise to higher yielding biofuel options can treble the abatement per land area for the present day, and potentially increase it by a factor five in the future. A focus on GHG abatement per area of arable land results in the land passenger transport sector to be of the highest priority due to the suitability of higher yielding biofuel options, followed by land goods transport, shipping and finally aviation. If gaseous fuels are not possible to introduce on a large scale, sectors where liquefied gaseous fuels are suitable become the priority, i.e. goods transport and shipping. The current practise of applying admixture quotas to sub-sectors of land transport renders a significantly lower climate benefit compared to an overall optimal usage, and a large societal transition is required before aviation biofuels become the climate optimal biomass usage. The direct importance of land use has thus far not received enough attention in terms of the economics of biofuels from dedicated crops, as well as for the greenhouse gas emissions policy. Biofuels produced from arable land can provide a strong GHG benefit if an expansion of arable land is hindered through redirecting land use, which requires a holistic policy approach.:Abstract ix Acknowledgments xi List of Publications xiii List of Acronyms xv I Introductory chapters 1 1 Background 3 1.1 Biofuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Technological Change and Modelling . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Aim and objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Methodology 9 2.1 Systems modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2 Model description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3 Results and discussion 17 3.1 Biofuel techno-economic potential and competitiveness . . . . . . . . . . . . 17 3.2 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.1 Resource base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.2 Biomass climate benefit in other sectors . . . . . . . . . . . . . . . . 20 3.2.3 Other renewable fuel options . . . . . . . . . . . . . . . . . . . . . . 21 3.2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.2.5 Applicability of results to other regions . . . . . . . . . . . . . . . . 22 4 Conclusions 25 4.1 Future research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Bibliography 29 Contribution to Appended Papers 33 Curriculum Vitae 35 CONTENTS II Appended papers 37 1 Competitiveness of advanced and conventional biofuels: Results from least-cost modelling of biofuel competition in Germany 39 2 Biomass price developments inhibit biofuel investments and research in Germany: The crucial future role of high yields 51 3 Relative greenhouse gas abatement cost competitiveness of biofuels in Germany 63 4 Climate optimal deployment of biofuels from crops in Germany 85
Biokraftstoffe sind eine erneuerbare Alternative zur Verringerung der Klimaauswirkungen des Verkehrs. Aufgrund der Vielseitigkeit der Biomasse und der Komplexität der Ökonomie und der Auswirkungen sind Biokraftstoffe Teil eines komplexen Systems, das hier aus einer Systemperspektive analysiert wird. Es werden mehrere Modelle entwickelt, um die Wettbewerbsfähigkeit verschiedener biogener Biokraftstoffoptionen als Teil eines Systems unter Verwendung verschiedener wirtschaftlicher und ökologischer Funktionseinheiten zu bewerten. Der Umfang ist auf Deutschland bis 2050 festgelegt. Die Kapital- und Rohstoffkosten wurden im Vergleich zu herkömmlichen Annahmen auf ein höheres Niveau angepasst. Die verschiedenen Funktionseinheiten führen zu unterschiedlichen Merit Order für die Biokraftstoffoptionen. Die derzeit verwendeten Biokraftstoffe, Raps-Saatgut-Biodiesel und Stärkepflanzen-Bioethanol, erwiesen sich als nicht wettbewerbsfähig, wenn man differenzierte und steigende Rohstoffkosten in Betracht zieht. Fortschrittliche flüssige Kraftstoffe waren nur unter extremen Annahmen wettbewerbsfähig, entgegen den üblichen Erwartungen. Stattdessen dominierte Ethanol auf Zuckerrübenbasis für einen Großteil der Zeitspanne beim Vergleich der Energiekosten, während synthetisches Erdgas (SNG) auf der Basis der Treibhausgasvermeidungskosten wettbewerbsfähig war, insbesondere bei einer schnellen Dekarbonisierung des Strommixes. Mit einer Funktionseinheit zur Reduzierung der Treibhausgasemissionen war Silagemais-basiertes Biomethan die beste Option, wobei SNG bei sehr hohen Anteilen an erneuerbaren Energien der Hintergrundsysteme konvergierte. Der Wechsel von der derzeitigen Praxis zu ertragreicheren Biokraftstoffoptionen kann die Verringerung pro Landfläche für die Gegenwart verdreifachen und in Zukunft möglicherweise um den Faktor fünf erhöhen. Die Fokussierung auf die Reduzierung von Treibhausgasen pro Ackerfläche führt dazu, dass der Landpersonenverkehr aufgrund der Eignung ertragreicherer Biokraftstoffoptionen, gefolgt von Landverkehr, Schifffahrt und schließlich Luftfahrt, höchste Priorität genießt. Wenn es nicht möglich ist, gasförmige Kraftstoffe in großem Maßstab einzuführen, werden Sektoren, in denen verflüssigte gasförmige Kraftstoffe geeignet sind, zur Priorität, d.h. Güterverkehr und Schifffahrt. Die aktuelle Praxis der Anwendung von Beimischungsquoten für Teilbereiche des Landverkehrs führt zu einem deutlich geringeren Klimanutzen im Vergleich zu einer insgesamt optimalen Nutzung, und es ist ein großer gesellschaftlicher Wandel erforderlich, bevor Biokraftstoffe aus der Luftfahrt zur klimaoptimalen Biomassenutzung werden. Die direkte Bedeutung der Landnutzung hat bisher nicht genügend Beachtung gefunden, sowohl in Bezug auf die Wirtschaftlichkeit von Biokraftstoffen aus Sonderkulturen als auch in Bezug auf die Treibhausgasemissionen. Biokraftstoffe, die von Anbaubiomasse hergestellt werden, können einen starken Treibhausgasvorteil bieten, wenn eine Ausweitung der Ackerfläche durch eine Neuausrichtung der Landnutzung behindert wird, was einen ganzheitlichen politischen Ansatz erfordert.:Abstract ix Acknowledgments xi List of Publications xiii List of Acronyms xv I Introductory chapters 1 1 Background 3 1.1 Biofuels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Technological Change and Modelling . . . . . . . . . . . . . . . . . . . . . . 6 1.3 Aim and objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2 Methodology 9 2.1 Systems modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2 Model description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3 Results and discussion 17 3.1 Biofuel techno-economic potential and competitiveness . . . . . . . . . . . . 17 3.2 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.1 Resource base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.2.2 Biomass climate benefit in other sectors . . . . . . . . . . . . . . . . 20 3.2.3 Other renewable fuel options . . . . . . . . . . . . . . . . . . . . . . 21 3.2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.2.5 Applicability of results to other regions . . . . . . . . . . . . . . . . 22 4 Conclusions 25 4.1 Future research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Bibliography 29 Contribution to Appended Papers 33 Curriculum Vitae 35 CONTENTS II Appended papers 37 1 Competitiveness of advanced and conventional biofuels: Results from least-cost modelling of biofuel competition in Germany 39 2 Biomass price developments inhibit biofuel investments and research in Germany: The crucial future role of high yields 51 3 Relative greenhouse gas abatement cost competitiveness of biofuels in Germany 63 4 Climate optimal deployment of biofuels from crops in Germany 85
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31

Murphy, Thomas Eugene. "Radiant and thermal energy transport in planktonic and benthic algae systems for sustainable biofuel production." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-05-2756.

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Biofuel production from microalgal biomass offers a clean and sustainable liquid fuel alternative to fossil fuels. In addition, algae cultivation is advantageous over traditional biofuel feedstocks as (i) it does not compete with food production, (ii) it potentially has a much greater areal productivity, (iii) it does not require arable land, and (iv) it can use marginal sources of water not suitable for irrigation or drinking. However, current algae cultivation technologies suffer from (i) low solar energy conversion effiencies, (ii) large thermal fluctuations which negatively affect the productivity, and (iii) large evaporative losses which make the process highly water intensive. This thesis reports a numerical study that address these key issues of planktonic as well as benthic algal photobioreactor technologies. First, radiant energy transfer in planktonic algal photobioreactors containing cells with different levels of pigmentation was studied. Chlamydomonas reinhardtii and its truncated chlorophyll antenna transformant tla1 were used as model organisms. Based on these simulations guidelines are derived for scaling the size and microorganism concentration of photobioreactors cultivating cells with different levels of pigmentation to achieve maximum photosynthetic productivity. To achieve this, the local irradiance obtained from the solution of the radiative transport equation (RTE) was coupled with the specific photosynthetic rates of the microorganisms to predict both the local and total photosynthetic rates in a photobioreactor. For irradiances less than 50 W/m2, the use of genetically modified strains with reduced pigmentation was shown to have negligible effect on increasing photobioreactor productivity. However, at irradiances up to 1000 W/m2, improvements of up to 30% were possible with cells having 63% less pigment concentration. It was determined that the ability of tla1 to transmit light deeper into the photobioreactor was the primary mechanism by which a photobioreactor using the modified strain can achieve greater productivity. Furthermore, it was determined photobioreactors using each strain have dead zones in which the local photosynthetic rate is negligible due to nearly complete light attenuation. These dead zones occur at local optical thicknesses greater than 169 and 275 in photobioreactors using the wild strain and the genetically modified strain, respectively. In addition, a thermal model of an algae biofilm photobioreactor was developed to assess the thermal fluctuations and evaporative loss rate of these novel photobioreactors under varying outdoor conditions. The model took into account air temperature, irradiance, relative humidity, and wind speed as inputs and computed the temperature and evaporative loss rate as a function of time and location in the photobioreactor. The model was run for a week-long period in each season using weather data from Memphis, TN. The range of the daily algae temperature variation was observed to be 13.2C, 12.4C, 12.8C, and 9.4C in the spring, summer, winter, and fall, respectively. Furthermore, without active cooling, the characteristic evaporative water loss from the system is approximately 6.3 L/m2-day, 7.0 L/m2-day, 4.9 L/m2-day, and 1.5 L/m2-day in the spring, summer, fall, and winter, respectively.
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32

Ho, Chun-Cheng, and 賀鈞鉦. "Study on Directive 2003/30/EC of 8 May 2003 on the promotion of the use of biofuels or other renewable fuels for transport." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/19656393571669389215.

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碩士
雲林科技大學
科技法律研究所
96
The Commission was requested to prepare proposals for the development of a reinvigorated European Energy Policy. One important element of such an approach would be means to address Europe’s over-dependency on imported oil and gas and to develop a coherent approach, based on a robust economic, environmental and social impact analysis, on how to progressively reduce this dependency. The biofuels play an important role in the European Union’s energy policy. European Union has passed directive 2003/30/EC which is concerning the promotion of the use of biofuels or other renewable fuels for transport on 8 May 2003(abbreviate as “Biofuel Directive 2003/30/EC of European Union”).The biofuels directive(2003/30/EC)expressed the clear intention of “promoting the use of biofuels… in each Member State, with a view to contributing to objectives such as meeting climate change commitments, environmentally friendly security of supply and promoting renewable energy sources” The biofuels directive sets indicative targets for the biofuel share of all transport fuels at 2 % by 2005, and 5.75 % by 2010..According to Article 4(2) of this directive, European Commission shall draw up an evaluation report for the European Parliament and for the Council on the progress made in the use of biofuels and other renewable fuels in the Member States by 31 December 2006 at the latest, and every two years thereafter. On the basis of this regulation, European Commission handed in the first report of execution situation and effect evaluation of biofuel directive 2003/30/EC. Referring the Biofuel Directive 2003/30/EC of European Union as the framework to the correlation policy as reference.Reviewing of the European Union’s biofuel obligations adaptability for Taiwan and see if our country’s policy in accordance with the principle of proportionality. These archives will be the main references in this paper. Expectedly, the research results can be need as the suggestions and responses of green energy promoting policy and legal measures in our country in the near future.
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33

Murphy, Thomas Eugene. "Artificial Leaf for Biofuel Production and Harvesting: Transport Phenomena and Energy Conversion." 2013. http://hdl.handle.net/2152/21581.

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Microalgae cultivation has received much research attention in recent decades due to its high photosynthetic productivity and ability to produce biofuel feedstocks as well as high value compounds for the health food, cosmetics, and agriculture markets. Microalgae are conventionally grown in open pond raceways or closed photobioreactors. Due to the high water contents of these cultivation systems, they require large energy inputs for pumping and mixing the dilute culture, as well as concentrating and dewatering the resultant biomass. The energy required to operate these systems is generally greater than the energy contained in the resultant biomass, which precludes their use in sustainable biofuel production. To address this challenge, we designed a novel photobioreactor inspired by higher plants. In this synthetic leaf system, a modified transpiration mechanism is used which delivers water and nutrients to photosynthetic cells that grow as a biofilm on a porous, wicking substrate. Nutrient medium flow through the reactor is driven by evaporation, thereby eliminating the need for a pump. This dissertation outlines the design, construction, operation, and modeling of such a synthetic leaf system for energy positive biofuel production. First, a scaled down synthetic leaf reactor was operated alongside a conventional stirred tank photobioreactor. It was demonstrated that the synthetic leaf system required only 4% the working water volume as the conventional reactor, and showed growth rates as high as four times that of the conventional reactor. However, inefficiencies in the synthetic leaf system were identified and attributed to light and nutrient limitation of growth in the biofilm. To address these issues, a modeling study was performed with the aim of balancing the fluxes of photons and nutrients in the synthetic leaf environment. The vascular nutrient medium transport system was also modeled, enabling calculation of nutrient delivery rates as a function of environmental parameters and material properties of the porous membrane. These models were validated using an experimental setup in which the nutrient delivery rate, growth rate, and photosynthetic yield were measured for single synthetic leaves. The synthetic leaf system was shown to be competitive with existing technologies in terms of biomass productivity, while requiring zero energy for nutrient and gas delivery to the microorganisms. Future studies should focus on utilizing the synthetic leaf system for passive harvesting of secreted products in addition to passive nutrient delivery.
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34

"Approaches to Engineering Synechocystis for Biofuel Production with Emphasis on Electron Transport Modifications." Doctoral diss., 2017. http://hdl.handle.net/2286/R.I.44171.

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abstract: The basic scheme for photosynthesis suggests the two photosystems existing in parity with one another. However, cyanobacteria typically maintain significantly more photosystem I (PSI) than photosystem II (PSII) complexes. I set out to evaluate this disparity through development and analysis of multiple mutants of the genetically tractable cyanobacterium Synechocystis sp. PCC 6803 that exhibit a range of expression levels of the main proteins present in PSI (Chapter 2). One hypothesis was that the higher abundance of PSI in this organism is used to enable more cyclic electron flow (CEF) around PSI to contribute to greater ATP synthesis. Results of this study show that indeed CEF is enhanced by the high amount of PSI present in WT. On the other hand, mutants with less PSI and less cyclic electron flow appeared able to maintain healthy levels of ATP synthesis through other compensatory mechanisms. Reduction in PSI abundance is naturally associated with reduced chlorophyll content, and mutants with less PSI showed greater primary productivity as light intensity increased due to increased light penetration in the cultures. Another question addressed in this research project involved the effect of deletion of flavoprotein 3 (an electron sink for PSI-generated electrons) from mutant strains that produce and secrete a fatty acid (Chapter 3). Removing Flv3 increased fatty acid production, most likely due to increased abundance of reducing equivalents that are key to fatty acid biosynthesis. Additional components of my dissertation research included examination of alkane biosynthesis in Synechocystis (Chapter 4), and effects of attempting to overexpress fibrillin genes for enhancement of stored compounds (Chapter 5). Synechocystis is an excellent platform for metabolic engineering studies with its photosynthetic capability and ease of genetic alteration, and the presented research sheds light on multiple aspects of its fundamental biology.
Dissertation/Thesis
Doctoral Dissertation Biology 2017
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35

Luk, Jason. "Pipeline Transport of Wheat Straw Biomass." Master's thesis, 2010. http://hdl.handle.net/10048/1391.

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This study experimentally evaluated wheat straw slurry pipelines. Tests were conducted to determine the particle properties of the biomass mixed in water over time. The saturated particle density of 1,060kg/m3 was reached after 24 hours, while the saturated moisture contents of 78.5% and 79.5% were later reached for particle sizes of 1/8 and 3/4" respectively. A pipeline loop was redesigned to operate with 1/8, 1/4", and 3/4" straw particle slurries at up to 30% wet basis concentrations. The modifications allowed measurements of pressure loss through a length of pipe. These measurements which show the influences of drag reducing fibre suspension. Straw particles added to water lowered the pressure loss, by suppressing turbulence at lower concentrations or higher velocities. Additional straw further improved the result, until the maximum concentration was reached. High concentrations create plugs, increasing the pressure loss. Longer straw particles can further reduce losses, but have lower maximum concentrations.
Engineering Management
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36

Abebe, Dereje Kebede. "A life cycle assessment on liquid biofuel use in the transport sector of Ethiopia." Diss., 2013. http://hdl.handle.net/10500/10601.

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Seed-oil based biodiesel production particularly biodiesel production from the nonedible oil seed bearing plant - Jatropha curcas L. - is a key strategic direction outlined in the biofuels strategy of the Government of Ethiopia. The main objective underlying the strategy include substitution of imported diesel oil used in the road transport sector while at the same time contributing to the local and global greenhouse gasses (GHG) reduction efforts. In this study the environmental benefits and costs of production and use of Jatropha biodiesel in the road transport sector of Ethiopia is assessed using a life cycle analysis (LCA) methodology. The analysis focused on determining the potential environmental impacts and net non-renewable energy saving potential of biodiesel from Jatropha oil-seeds using the following metrics: (i) Net Greenhouse Gas (GHG) reduction, and (ii) Net Energy Balance (NEB) relative to diesel oil. The study shows that the net GHG emissions reduction potential of Jatropha Methyl Ester (JME) is highly influenced by the magnitude of initial carbon loss occurring in the process of conversion of different land uses to Jatropha plantation, and less so on other unit processes of JME production system analysed. The NEB of JME relative to use of diesel oil per functional unit of one GJ is less sensitive to impacts of land use change and is generally positive. Where no land use change impacts is considered, or where Jatropha is grown on lands with low carbon stock such as grasslands, substitution of diesel oil with JME in Ethiopia can provide GHG emission reduction of about 43%, and for each MJ of JME produced the nonrenewable energy requirement will be 0,38 MJ. Production of JME by converting lands with high above ground, below ground and/or soil carbon stocks such as shrub lands or well stocked forest lands will result in net loss of carbon and require ecological carbon payback time of 50 to hundreds of years. The impact of introducing and use of JME-diesel oil blends by Anbassa City Bus Services Enterprise (ACBSE) bus fleets shows that, displacement of diesel oil with JME that have positive GHG reduction potential, will also contribute to the reduction of air pollutants and improvement of ambient air quality in Addis Ababa. Two key recommendations of this research work are that to ensure environmental sustainability of biodiesel production from Jatropha seeds (i) land availability and land suitability assessment for estimating the potential available land for Jatropha (and other oil-seed bearing plants) shall be conducted, and (ii) minimum requirements on GHG reduction and NEB requirements on biodiesel shall be established.
Environmental Sciences
M. Sc. (Environmental Management)
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37

Müller, Harald. "Biogene und fossile Kraftstoffproduktion an norddeutschen Hafenstandorten: ein ökonomischer, ökologischer und energetischer Vergleich der Wertschöpfungsketten." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-000D-EF3E-8.

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38

Chen, Shih-Wei, and 陳仕偉. "Research on the European Union Renewable Energy Law – Examples on the Sustainable Development Criteria of Biofuel in the Transport Sector." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/39174222534732991927.

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碩士
國立雲林科技大學
科技法律研究所碩士班
101
It is difficult to resolve the problem on the growing shortage of traditional fossil fuel and climate change, such as nuclear energy issue and geopolitics for energy security. Reviewing the international trend on renewable legislations and policies, the development of sustainable and alternative renewable energy has become the main energy policy objective in many countries, such as European Union, United States and other leading countries. As the largest regional economic community in the world, European Union laid down three main legislations on the renewable energy, there are “Renewable Electricity Directive”(2001/77/EC), “Promototion Biofuel Directive” (2003/30/EC) and “ Renewable Energy Directive” (2009/28/EC, RED), By Focusing the RED, this thesis will analysis regulations related to the Environmental Sustainability Criteria in RED, and introduce the proposal of amending the RED. By researching the renewable energy in the European Union, We expect there are some proper suggestions for Taiwan through this stydy
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