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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

La contribution de la traduction à l'expansion lexicale du sesotho / The contribution of translation to the lexical expansion of Sesotho

Sebotsa, Mosisili 22 November 2016 (has links)
Si la traduction est simplement définie comme un processus de communication bilingue dont le but général est de reproduire en langue cible un texte qui soit fonctionnellement équivalent au texte de départ (Reiss 2004 : 168-169), l’approche empruntée dans la présente thèse est celle d’une opération interculturelle et systématique qui vise à capturer le message issu d’une langue étrangère, à le décrypter en tenant en compte des nuances culturelles ou inhérentes à la discipline, et à le rendre le plus clairement possible en se servant d'éléments linguistiques et extralinguistiques compréhensibles dans la langue du locuteur cible. L'objectif est de déterminer la contribution de la traduction à l’expansion lexicale du sesotho, domaine qui demeure peu exploré par les spécialistes de cette langue. La problématique de ce travail repose sur la constatation que les néologismes en sesotho ne sont pas documentés de manière satisfaisante, si bien qu’il est difficile d'évaluer la contribution de la traduction à l’expansion lexicale. Les études antérieures sur la morphologie, la dérivation, la composition, l’emprunt et la dénomination s’appuient sur la mesure de la productivité, soulevant la question de savoir si la traduction en soi contribue à l’enrichissement terminologique du sesotho. Le point de départ de la thèse est l'hypothèse selon laquelle l’interaction avec le monde européen a nécessité de traduire de nombreux concepts qui n’existaient pas dans les systèmes traditionnels du Lesotho, ce qui a entraîné un nouveau dynamisme qui a permis de combler des lacunes terminologiques évidentes et de s’ouvrir et de s’adapter aux nouvelles réalités. Pour mettre cette hypothèse à l’épreuve et arriver à des conclusions éclairées et fiables, je cherche à répondre à trois questions : 1) Quelle est la structure des mots sesothos par rapport à celle de l’anglais en tant que langue source de traduction en sesotho, et du français en tant que langue de rédaction de la thèse ? 2) Etant donné que le sesotho est utilisé concomitamment avec l’anglais sans pour autant être la langue d'une culture inventrice en matière technologique, quel est le rôle que joue l’emprunt dans son expansion lexicale ? 3) D’un point de vue lexicologique, comment le sesotho répond-il aux besoins terminologiques dans les domaines de spécialité techno-scientifiques ? Pour y répondre, je m'appuie sur Doke (1954) et Matšela et al. (1981) pour situer le sesotho parmi les langues bantoues, préciser les fonctions du préfixe classificateur et établir la différence entre les composés sesothos d'une part et les composés anglais et français d'autre part. J’utilise ensuite la théorie avancée par Lederer (1990) pour démontrer l’influence syntaxique, sémantique et morphologique que l’anglais a sur le sesotho et pour présenter les différents procédés d’emprunt du sesotho. Diki-Kidiri (2008), Dispaldro et al. (2010) et Baboya (2008) démontrent la nécessité de faire appel aux informateurs-spécialistes pour confirmer l’hypothèse de départ. Les résultats obtenus mettent en évidence qu’en effet, la traduction a contribué à l’expansion du sesotho moderne, bien que cela n’ait pas été documenté, d’où la recommandation d'un travail collaboratif entre lexicologues au Lesotho, au Botswana, en Namibie et en Afrique du Sud, pour ouvrir de nouvelles perspectives d’études linguistiques sur le sesotho et pouvoir suivre et mesurer l’évolution de la langue. / Whilst translation is simply defined as a communication process whose main objective is to reproduce in the target language a text that is functionally equivalent to the source text (Reiss 2004: 168-169), the approach taken in this study views translation as an intercultural and systematic operation whose objective is to capture the message from the foreign language, to decrypt it taking into account cultural nuances or those inherent in the field at hand and to render it in the clearest possible manner using linguistic and extra linguistic elements which are comprehensible to the speaker of the target language. This study is aimed at determining the contribution of translation to the lexical expansion of Sesotho, an area which has been little explored by specialists of the language. The core issue is centred on the observation that Sesotho neologisms are not well documented, so that it is hard to measure the contribution of translation towards the lexical expansion of Sesotho. Analyses of morphology, derivation, compounding, borrowing and denomination are mainly focused on productivity in order to determine whether translation as a discipline contributes towards the creation of new words in the language.The study begins by positing the hypothesis that the interaction with the Western world necessitated the translation of numerous concepts which were absent from the then existing Sesotho systems. This process of interaction contributed a new dynamism that helped the language to bridge the terminological gap, to open up and adapt to new realities. In order to put this hypothesis to the test and arrive at well-researched and reliable conclusions, I attempt to probe three issues of concern: firstly, what is the structure of the Sesotho language compared to that of the English language as the source language of most translations into Sesotho and compared to that of the French language as the language in which this study is presented? Secondly, considering that Sesotho is used simultaneously with English even though it is not a techno-scientifically inventing language, what is the role played by the processes of borrowing in the lexical expansion of Sesotho? Thirdly, from the word-formation point of view, how does Sesotho respond to the terminological deficiencies in various fields of specialisation?To address these issues, Doke (1954) and Matšela et al. (1981) serve as references to situate Sesotho among the Bantu languages, to highlight the functions of the class prefix and to establish the difference between Sesotho and English and French compounding. Secondly, the theory advanced by Lederer (1990) serves as a springboard to analyse the syntactic, semantic and morphological influences that English has on Sesotho and to present the different borrowing processes. The third issue is addressed based on the theories presented by Diki-Kidiri (2008) while the theories proposed by Dispaldro et al. (2010) and Baboya (2008) led to the decision to call upon specialist informants to confirm the original hypothesis. The results obtained provide evidence that translation has, in fact, contributed to the lexical expansion of modern Sesotho, even though this has not been well documented. The study recommends collaborative work between Lesotho, Botswana, Namibian and South African linguists in order to open new avenues of linguistic studies on Sesotho with the aim to measure and monitor the evolution of the language.
312

Reducing industrial use of fossil raw materials:techno-economic assessment of relevant cases in Northern Finland

Arvola, J. (Jouko) 28 November 2011 (has links)
Abstract Climate change and global warming are currently widely discussed topics, both of which potentially impact all the nations and industries. Carbon dioxide (CO2) and other green house gases (GHG) are seen as a major challenge. This doctoral dissertation aims to conduct techno-economic calculations on the possibilities of reducing the industrial use of fossil raw materials in Northern Finland. This doctoral dissertation analyses industrial CO2 emissions from five complementary perspectives: identifying significant potential industrial plants, analysing the replacement of fossil raw materials with wood biomass, considering combining different industrial sectors, the potential of biogas as industrial raw material, and estimating the economic significance of moisture in wood fuel. The study started by analysing all the relevant 262 regional environmental permits to find the significant industrial users of synthesis gas in the studied region. Processes used by each identified case were analysed carefully to identify the most potential change possibilities. Economic calculations were conducted for these cases using true production volumes. The aim was to reach solutions that were economically sound. Five industrial sites were identified as potential cases for replacing raw materials of synthesis gas or hydrogen with renewable alternatives. These sites include the Rautaruukki steel mill, Eka Chemicals’ hydrochloric acid plant, Kemira’s formic acid plant, Kemira’s hydrogen peroxide producing plant, and Talvivaara mining’s hydrogen plant. The main implications of this dissertation include providing tips for industrial managers, regional decision makers and legislators. Managers of companies with high energy consumption and/or high usage of fossil raw materials in their products can benefit from the results of this dissertation the most. Managers should conduct similar calculations, as in this study, by using exact figures relevant to their processes and raw materials. This doctoral dissertation also suggests finding new solutions for replacing fossil raw materials by combining two different industrial sectors, e.g. steel and chemical industries. Regional decision makers may utilise the calculations presented in this doctoral dissertation when developing regional strategies. / Tiivistelmä Ilmaston muutos ja globaali lämpeneminen ovat tällä hetkellä laajasti keskusteltuja aiheita, ja ne vaikuttavat kaikkiin maihin ja kaikkiin teollisuuden aloihin. Hiilidioksidi (CO2) ja muut kasvihuonekaasut nähdään suurena haasteena. Tämä väitöskirja pyrkii teknistaloudellisten laskelmien avulla tutkimaan mahdollisuuksia vähentää fossiilisten raaka-aineiden käyttöä Pohjois-Suomen alueella. Tämä väitöskirja analysoi teollisia CO2-päästöjä viidestä toisiaan täydentävästä näkökulmasta: identifioimalla merkittäviä teollisia tuotantolaitoksia, analysoimalla fossiilisten raaka-aineiden korvaamista puubiomassalla, tutkimalla erilaisten teollisten tuotantolaitosten yhdistämistä, tutkimalla biokaasun käyttöä mahdollisena teollisuuden raaka-aineena ja arvioimalla kosteuden taloudellista merkitystä puupolttoaineessa. Tutkimus alkoi analysoimalla kaikki alueen identifioidut 262 ympäristölupaa, jotta merkittävät synteesikaasun käyttäjät tulisivat esille. Jokaisen löydetyn tapauksen tuotantoprosessit analysoitiin huolellisesti, jotta potentiaalisimmat muutosmahdollisuudet huomioitaisiin. Teknistaloudellisia laskelmia tehtiin näille tapauksille käyttämällä todellisia tuotantolukuja. Tarkoituksena oli löytää taloudellisesti kannattavia vaihtoehtoja. Viisi teollista tuotantolaitosta identifioitiin tapauksiksi, joissa synteesikaasun tai vedyn raaka-aine voitaisiin korvata uusiutuvilla raaka-ainevaihtoehdoilla. Nämä tuotantolaitokset olivat Rautaruukin terästehdas, Eka Chemicalsin kloorivetyhapon tuotantolaitos, Kemiran muurahaishappotehdas, Kemiran vetyperoksiditehdas ja Talvivaaran kaivoksen vedyn tuotantolaitos. Tärkeimmät implikaatiot tästä väitöskirjatyöstä sisältävät pohdittavia ajatuksia teollisille toimijoille, alueellisille päätösten tekijöille ja lainsäätäjille. Korkean energian kulutuksen ja/tai suurten fossiilisten raaka-ainekäyttöjen yhtiöissä päätöksentekijät voivat hyödyntää parhaiten tämän väitöskirjan tuloksia. Päätöksentekijät voisivat käyttää esimerkkeinä tämän väitöskirjan laskelmia tehdessään omia analyyseja, jolloin heidän tulisi käyttää tarkkoja lukuja yritystensä prosesseista ja raaka-ainekäytöistä. Tämä väitöskirja ehdottaa myös etsimään uusia ratkaisuja fossiilisten raaka-aineiden korvaamisessa yhdistämällä tuotannollisesti erilaisia teollisia sektoreita esimerkiksi teräksen ja kemian tuotteiden valmistuksen. Alueelliset päätösten tekijät voivat hyödyntää väitöskirjassa esitettyjä laskelmia alueellisten strategioiden kehitystyössä.
313

Stavebně technologický projekt ayurvédského pavilonu v Počátkách / Construction-technological project of Ayurvedic pavilion in Počátky

Lisý, Ondřej January 2020 (has links)
The diploma thesis deals with realization of an Ayurvedic pavilion in the premises of Saint Katerina Resort. The proposed new compound is designed to extend the leisure services of the Saint Katerina Resort in Počátky. The feasibility study of the main technological stages of the project is solved in this diploma thesis. The construction of the object is described in the technical report. Both a detailed itemized budget of the construction and a detailed timetable to show the duration of each process is elaborated for the construction technology project. Futhermore, the design of site construction equipment, design of machine assembly, time deployment of machines and staff balance is elaborated. The project includes a technological regulation of the realization of the skeleton supporting frame structure and both control and test schedule. The work safety for the assembly of the wooden building supporting frame is composed.
314

A techno-socio-economic potential assessment of organic waste-to- energy conversion through biogas technology for rural households in Vhembe District of Limpopo

Rasimphi, Thilivhali Eugene 02 February 2016 (has links)
MENVSC / Department of Ecology and Resource Management
315

Fenomén filmu - informace - společnost / Phenomenon of Film - Information - Society

Vodrážková, Katrin January 2013 (has links)
The dissertation presents an analysis of film and photographic media as two specific information systems. It is based mainly on the system theory of Niklas Luhmann, the basis upon which film is understood as a social system. The phenomenon of film is further developed as an imaging technique in the contemporary information society and electronic culture. The work shows new forms of imaging in film, but also a comparison of imaging techniques in the photographic medium. The goal of the dissertation is to contribute to a more detailed understanding of moving images and to develop the possibilities of film, which has the potential to become a future information system. Powered by TCPDF (www.tcpdf.org)
316

Economic Engineering Modeling of Liberalized Electricity Markets: Approaches, Algorithms, and Applications in a European Context: Economic Engineering Modeling of Liberalized Electricity Markets: Approaches, Algorithms, and Applications in a European Context

Leuthold, Florian U. 08 January 2010 (has links)
This dissertation focuses on selected issues in regard to the mathematical modeling of electricity markets. In a first step the interrelations of electric power market modeling are highlighted a crossroad between operations research, applied economics, and engineering. In a second step the development of a large-scale continental European economic engineering model named ELMOD is described and the model is applied to the issue of wind integration. It is concluded that enabling the integration of low-carbon technologies appears feasible for wind energy. In a third step algorithmic work is carried out regarding a game theoretic model. Two approaches in order to solve a discretely-constrained mathematical program with equilibrium constraints using disjunctive constraints are presented. The first one reformulates the problem as a mixed-integer linear program and the second one applies the Benders decomposition technique. Selected numerical results are reported.
317

An airports’ need of change to go 100% green using an energy storage system and solar power : Integration of energy storage system and photovoltaics to an existing system

Törnberg, Carl January 2022 (has links)
This thesis explores what Karlstad Airport needs to go 100% green. Photovoltaics are assumed to be installed at the facility and a Hydrogen Energy Storage System and Battery Energy Storage System will be evaluated to reduce peaks during charging of the planes. Different power peak limits are explored as well as different sized Energy Storage Systems and later evaluated economically. A method to find the cheapest possible system is created with some assumptions and is then used to evaluate throughout the whole dataset. In the end any of the different sized Energy Storage Systems reduces the profitability when considering each systems expected lifecycle.
318

Assessment of biochar potential as a land-based emission mitigation measure in Colombia

Torres Morales, Eileen Jimena January 2022 (has links)
There is an urgent need to mitigate carbon emissions to the atmosphere to reduce the negative effects of climate change. Countries have pledged national strategies to reach their climate change mitigation goals in their Nationally Determined Contributions (NDC). In the case of Colombia, the country envisions becoming carbon neutral by 2050.  A pathway to reach this goal is emission reduction through nature-based solutions (NBS). Biochar is an NBS with the potential to be used as a land-based emission mitigation technology. Records indicate that it was first used by indigenous communities in the Amazon about a thousand years ago. Biochar can be obtained through thermochemical conversion by slow pyrolysis of residual biomass. The original organic carbon present in the biomass is sequestered in the biochar as it is pyrolyzed and thus, CO2 emissions are prevented. Biochar is not yet considered in Colombia´s carbon neutrality strategy. The aim of this thesis project is to investigate the potential of biochar production in Colombia as a land-based mitigation technology (LMT). Therefore, a comprehensive assessment is performed with the purpose of identifying the status of biochar in the country. The motivation behind the assessment is to gain an understanding of the variables involved in biochar production. Factors such as the production sectors involved, feedstocks, production technologies, project costs and emission mitigation are of interest. The study explores these factors by following five methodological steps. First, the current research on the technology is mapped to understand biochar’s status at a national level. Second, experts are interviewed to collect their views regarding biochar and a PESTEL (Political, Economic, Social, Technological, Environmental & Legal) analysis is employed based on their point of view on the technology. Third, the potential sources of residual biomass which could be used to produce biochar in the agricultural sector are quantified. The approach to biochar’s potential is enriched with a focused in-person case study of biochar production from oil palm residues. Fourth, these residual biomass sources are subsequently employed to estimate the emissions sequestered in their biochar production. Lastly, project feasibility implementation is evaluated through a techno-economic to identify the project’s main cost drivers. The results are then discussed using a SWOT (Strength, Weaknesses, and Opportunities & Threats) analysis. The existing studies and the local experts’ opinion indicate that biochar potential is in the agricultural sector and that it can be thought of for soil adaptation. Biochar’s emission mitigation is considered an added value. In 2021, the agricultural sector produced near 73 million tonnes of agricultural products. The residues from agriculture could be used for biochar production. If the residues from the most produced agricultural products are transformed into biochar, about 1 to 2,2 tonne of CO2 per tonne of biochar could be avoided. The published literature and the in-person study visit confirmed that the largest advance in biochar production and use in Colombia is in the oil palm sector. Palm kernel shell, fibre and empty fruit bunches are the oil palm residues that could be used to produce biochar. From 1 tonne of these three oil palm residues, about 60 kg of biochar can be obtained. The results show that currently there is no market for trading with biochar in Colombia. High investments, transport and feedstock costs are identified obstacles. An Advanced Technology pyrolizer cost can cost around 330.000 USD while a Basic Technology one can be around 100 USD. Taxes associated with revenue from the biochar trade can negatively impact a biochar project’s feasibility. In this study, a price for biochar is estimated using break-even analysis. Under the assumptions used, the biochar price per tonne is around 200 to 1.000 USD. Price variability is explained in the technologies used for production, feedstock biomass availability and variable revenues from biochar sales. / Koldioxidutsläppen till atmosfären behöver minskas för att undvika de negativa effekterna av klimatförändringar. Olika länder har presenterat på sina nationellt fastställda bidrag (NDC) hur sina mål för begränsning av klimatförändringarna skulle kunna uppnås. I Colombia är planen att uppnå koldioxidneutralitet år 2050. Ett sätt att uppnå detta mål är att minska utsläpp genom naturbaserade lösningar (NBS). Biokol är en NBS som kan användas som landbaserade åtgärder för att minska växthusgasutsläpp eller öka koldioxidupptag. Forskning har bevisat att biokol användes i Amazonas för ungefär tusen år sedan. Biokol framställs genom långsam pyrolys av restprodukter av biomass. Kolet i biomassan binds i biokolet genom pyrolysis, vilket förhindrar koldioxidens utsläppning till atmosfären. Biokol inkluderas ännu inte i Colombias strategi för koldioxidneutralitet. Syftet med detta projekt är att undersöka biokolets produktionspotential i Colombia son ett landbaserade åtgärder (LMT). En analys gjordes för att identifiera statusen av biokol runt om i landet. Faktorer såsom berörda produktionssektorer, råvaror, produktionstekniker, projektkostnader och koldioxidutsläppen var av intresse. Studien undersöker faktorerna ovan genom att tillämpa en femstegsmetod. Först identifierades den aktuella forskningen om biokol i Colombia. Sedan intervjuades experter för att samla in deras åsikter om biokol och en PESTEL analys (Political, Economic, Social, Technological, Environmental & Legal) användes. Nästa steg i metoden var att kvantifiera potentialen av restprodukter inom jordbrukssektorn. Detta steg kompletterades med en fallstudie som fokuserade på biokolproduktion från rester från oljepalmer och sedan beräknades utsläppen som binds i biokol. Till sist utvärderades projektets genomförbarhet genom en teknoekonomisk analys som identifierade viktigaste drivkrafterna bakom kostnaderna. Resultaten diskuterades med hjälp av en SWOT analys (Strength, Weaknesses, and Opportunities & Threats). Experter och forskningsresultat om biokol i Colombia anger att det finns stor potential nom jordbrukssektor där biokol skulle kunna användas för jordförbättring, medan utsläppsminskningar endast anses vara en ytterligare fördel. År 2021 Colombias jordbrukssektor producerade nästan 73 millioner tonne av jordbruksprodukter och restprodukter från jordbruket kan användas för produktion av biokol. För varje ton biokol som produceras undviks ungefär 1 till 2,2 tonne koldioxid. Litteraturen och studiebesöket bekräftade att största framsteget inom produktion och användning av biokol i Colombia händer inom oljepalmssektorn. Palmkärnor, fibrer och tomma fruktknippar är restprodukterna som kan användas för att producera biokol. En ton av dessa tre typer av oljepalmsrester ger cirka 60 kg biokol. Resultaten visar att det inte finns en marknad för biokol i Colombia. Höga investeringskostnader, transport-och råvarukostnader är främsta hindarna som identifierades. En pyrolysanläggning med avancerad teknik kostar cirka 330 000 US-dollar, medan en pyrolysanläggning med grundläggande teknik kostar cirka 100 US -dollar. Skatter på inkomster från biokolsförsäljning kan ha en negativ effekt på genomförbarhet. Studien uppskattas ett pris för biokol med hjälp av en break-even-analys och visar att cirka 200 till 1.000 USD per tonne biokol vore ett möjligt prisintervall. Prisvariationerna förklaras av tekniken som används för produktion, tillgång på biomassa som råvara och varierande intäkter från biokolförsäljning.
319

Modeling and Optimization of Photovoltaic Installations at Urban Scale

Fuster Palop, Enrique 15 January 2024 (has links)
Tesis por compendio / [ES] El sector de la edificación representa el 20% y el 40% de la energía primaria mundial, contribuyendo al 30% de las emisiones de CO2, un desafío amplificado por el crecimiento de la población. Sin embargo, el creciente interés en las fuentes de energía renovables ya maduras, como la energía solar fotovoltaica (PV), ofrece oportunidades para mitigar los anteriores impactos, así como potenciales beneficios económicos, ambientales y sociales. El presente trabajo investiga las posibilidades y limitaciones en el despliegue masivo de sistemas de autoconsumo fotovoltaico (PVSC) en áreas urbanas desde una perspectiva de planificación urbana, considerando las limitaciones técnicas y económicas actuales. Con este fin, esta tesis emplea estrategias basadas en datos para desarrollar modelos físicos y modelos ágiles basados en regresiones como herramientas de evaluación del potencial técnico y económico de los sistemas PVSC en contextos urbanos. En primer lugar, se ha desarrollado y validado un submodelo empírico de producción fotovoltaica con mediciones climáticas y de producción recopiladas de una planta fotovoltaica de 50MW en funcionamiento. Además, se han investigado varias mejoras en el modelado del performance ratio (PR) en entornos de baja irradiancia. En la segunda etapa de esta investigación, el submodelo anterior se ha integrado en un modelo tecnoeconómico 3D basado en sistemas de información geográfica (GIS) capaz de evaluar el PVSC económico para una muestra de edificios residenciales. Además, el modelo incorpora modelos de sombras y estimaciones de demanda eléctrica horaria para evaluar una muestra de edificios residenciales. Una base de datos de simulación, derivada de los resultados anteriores, ha permitido el desarrollo de una metodología para entrenar un modelo basado en regresión y con ello estimar la producción y el periodo de retorno económico (PB) a escala de edificio con una precisión asumible para fines de planificación energética. Como último paso, se mejoró el submodelo de demanda empleando datos reales agregados de series temporales para múltiples patrones de consumo y proporcionando estimaciones realistas para otras tipologías de edificios. Además de las restricciones espaciales, el modelo optimiza el tamaño de las instalaciones según su demanda y limitaciones económicas, maximizando la relación entre autosuficiencia (SS) y el PB. Además, la metodología basada en regresión se ha ampliado para estimar, además del retorno de la inversión, múltiples indicadores clave de desempeño (KPIs) como la tasa interna de retorno (IRR), la tasa de autoconsumo (SC) y SS. A través de una adecuada identificación de predictores y una metodología de entrenamiento y validación, estas correlaciones permitieron estimaciones de rendimiento con una desviación aceptable respecto al modelo físico. La disponibilidad de datos relacionados con la construcción está aumentando progresivamente en la mayoría de los países, lo que permite una amplia aplicación y generalización de las metodologías propuestas y reduce el costo de simulación de estos estudios para cubrir áreas urbanas más extensas. Como aplicación de las metodologías anteriores, se analizaron los resultados del potencial económico fotovoltaico del parque inmobiliario completo de un municipio mediterráneo bajo diferentes escenarios económicos y de demanda a escala de edificio y municipal. Para el escenario que cumple con la regulación actual en España, la SS municipal oscila entre el 22%-43% para los escenarios más optimista y pesimista, respectivamente. El dimensionamiento óptimo de las instalaciones según las curvas de carga en la modalidad de Net Billing (NB) es crucial para obtener resultados económicos competitivos. En consecuencia, la generación fotovoltaica anual representó el 68% del consumo eléctrico total anual. / [CA] El sector de l'edificació representa el 20% i el 40% de l'energia primària mundial, contribuint al 30% de les emissions de CO2, un desafiament amplificat pel creixement de la població. No obstant això, el creixent interés en les fonts d'energia renovables ja madures, com l'energia solar fotovoltaica (PV), ofereix oportunitats per a mitigar els anteriors impactes, així com potencials beneficis econòmics, ambientals i socials. El present treball investiga les possibilitats i limitacions en el desplegament massiu de sistemes PVSC en àrees urbanes des d'una perspectiva de planificació urbana, considerant les limitacions tècniques i econòmiques actuals. A aquest efecte, aquesta tesi empra estratègies basades en dades per a desenvolupar models físics i models àgils basats en regressions com a eines d'avaluació del potencial tècnic i econòmic dels sistemes PVSC en contextos urbans. En primer lloc, s'ha desenvolupat i validat un submodel empíric de producció fotovoltaica amb mesuraments climàtics i de producció recopilats d'una planta fotovoltaica de 50MW en funcionament. A més, s'han investigat diverses millores en el modelatge del performance ràtio (PR) en entorns de baixa irradiància. En la segona etapa d'aquesta investigació, el submodel anterior s'ha integrat en un model tecnoeconòmic 3D basat en sistemes d'informació geográfica (GIS) capaç d'avaluar el PVSC econòmic per a una mostra d'edificis residencials. A més, el model incorpora models d'ombres i estimacions de demanda elèctrica horària per a avaluar una mostra d'edificis residencials. Una base de dades de simulació, derivada dels resultats anteriors, ha permés el desenvolupament d'una metodologia per a entrenar un model basat en regressió i amb això estimar la producció i la període de retorn econòmic (PB) a escala d'edifici amb una precisió assumible per a fins de planificació energètica. Com a últim pas, es va millorar el submodel de demanda emprant dades reals agregats de sèries temporals per a múltiples patrons de consum i proporcionant estimacions realistes per a altres tipologies d'edificis. A més de les restriccions espacials, el model optimitza la grandària de les instal·lacions segons la seua demanda i limitacions econòmiques, maximitzant la relació entre la taxa d'autosuficiència (SS) i PB. A més, la metodologia basada en regressió s'ha ampliat per a estimar, a més del retorn de la inversió, múltiples indicadors clau d'acompliment (KPIs) com la taxa interna de retorn (IRR), la taxa d'autoconsum (SC) i la SS. A través d'una adequada identificació de predictors i una metodologia d'entrenament i validació, aquestes correlacions van permetre estimacions de rendiment amb una desviació acceptable respecte al model físic. La disponibilitat de dades relacionades amb la construcció està augmentant progressivament en la majoria dels països, la qual cosa permet una àmplia aplicació i generalització de les metodologies proposades i redueix el cost de simulació d'aquests estudis per a cobrir àrees urbanes més extenses. Com a aplicació de les metodologies anteriors, es van analitzar els resultats del potencial econòmic fotovoltaic del parc immobiliari complet d'un municipi mediterrani baix diferents escenaris econòmics i de demanda a escala d'edifici i municipal. Per a l'escenari que compleix amb la regulació actual a Espanya, la taxa d'autosuficiència municipal oscil·la entre el 22%-43% per als escenaris més optimista i pessimista, respectivament. El dimensionament òptim de les instal·lacions segons les corbes de càrrega en la modalitat de Net Billing (NB) és crucial per a obtindre resultats econòmics competitius. En conseqüència, la generació fotovoltaica anual va representar el 68% del consum elèctric total anual. / [EN] The building sector in developed countries consumes 20% to 40% of global primary energy, contributing to 30% of the CO2 emissions, a challenge amplified by urban population growth. However, the rising interest in mature renewable energy sources, such as solar photovoltaic (PV), offers opportunities to mitigate these impacts and potential economic, environmental, and social benefits. The present research investigates the possibilities and constraints in the massive deployment of photovoltaic self-consumption (PVSC) systems in urban areas from an urban planning perspective, considering the current technical and economic limitations. To this end, this thesis employs data-driven strategies to develop both bottom-up physical and agile regression-based models as assessment tools for the technical and economic potential of PVSC systems in urban contexts. First, an empirical PV production submodel has been developed and validated with climate and production measurements collected from a 50MW utility-scale in operation. Additionally, several improvements in modeling the performance ratio (PR) in low-irradiance environments have been investigated. In the second stage of this research, the previous submodel has been integrated into a physical 3D GIS-based techno-economic model capable of assessing the economic PVSC for a sample of residential buildings. Additionally, the model incorporates shadow modeling and hourly electric demand estimations to assess sample residential buildings. A simulation database, derived from the previous results, has allowed the development of a methodology to train a regression-based model to estimate the production and the economic payback (PB) at a building scale with an assumable accuracy for energy planning purposes. As the last step, the demand submodel was improved by employing real aggregated time series data for multiple consumer patterns and providing realistic estimations for other building typologies. In addition to spatial restrictions, the model optimizes the sizing of the facilities according to their demand and economic constraints, maximizing the relationship between self-sufficiency (SS) and PB. Furthermore, the regression-based methodology has been extended to estimate, besides the payback, multiple key performance indicators such as internal rate of return (IRR), self-consumption rate (SC), and SS. Through an appropriate predictor identification and a training and validation methodology, these correlations allowed performance estimations with an acceptable deviation compared with the physical model. The availability of building-related data is progressively increasing in most countries, enabling widespread application and generalization of the proposed methodologies and reducing the simulation cost of these studies to cover larger urban areas. As an application of the previous methodologies, a complete-census economic PV potential results of a Mediterranean municipality's building stock was performed under different demand and economic scenarios at a building and municipality scale. For the scenario that meets the current regulation in Spain, the municipality SS ranged between 22%-43% for the most optimistic and pessimistic scenarios, respectively. The optimal sizing of the facilities according to the load curves in the Net Billing (NB) modality is crucial to obtaining competitive economic results. Consequently, the annual PV generation represented 68% of the annual total electricity consumption of the municipality for a net billing scenario, while a net metering scenario represented 103%. Owing to economies of scale and high demand intensity, a higher profitability was found in rooftops of apartment blocks and industrial buildings, which also achieve the highest savings in emissions. / Fuster Palop, E. (2023). Modeling and Optimization of Photovoltaic Installations at Urban Scale [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202061 / Compendio
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Electric Road Systems : A feasibility study investigating a possible future of road transportation / Elektriska vägsystem : Genomförbarhetsstudie kring en möjlig framtid för vägstransport

Singh, Archit January 2016 (has links)
The transportation sector is a vital part of today’s society and accounts for 20 % of our global total energy consumption. It is also one of the most greenhouse gas emission intensive sectors as almost 95 % of its energy originates from petroleum-based fuels. Due to the possible harmful nature of greenhouse gases, there is a need for a transition to more sustainable transportation alternatives. A possible alternative to the conventional petroleum-based road transportation is implementation of Electric Road Systems (ERS) in combination with electric vehicles (EVs). ERS are systems that enable dynamic power transfer to the EV's from the roads they are driving on. Consequently, by utilizing ERS in combination with EVs, both the cost and weight of the EV-batteries can be kept to a minimum and the requirement for stops for recharging can also be eliminated. This system further enables heavy vehicles to utilize battery solutions. There are currently in principal three proven ERS technologies, namely, conductive power transfer through overhead lines, conductive power transfer from rails in the road and inductive power transfer through the road. The aim of this report is to evaluate and compare the potential of a full-scale implementation of these ERS technologies on a global and local (Sweden) level from predominantly, an economic and environmental perspective. Furthermore, the thesis also aims to explore how an expansion of ERS might look like until the year 2050 in Sweden using different scenarios. To answer these questions two main models (global and Swedish perspective) with accompanying submodels were produced in Excel. The findings show that not all countries are viable for ERS from an economic standpoint, however, a large number of countries in the world do have good prospects for ERS implementation. Findings further indicated that small and/or developed countries are best suited for ERS implementation. From an economic and environmental perspective the conductive road was found to be the most attractive ERS technology followed by overhead conductive and inductive road ERS technologies. The expansion model developed demonstrates that a fast expansion and implementation of an ERS-based transportation sector is the best approach from an economical perspective where the conductive road technology results in largest cost savings until 2050. / Transportsektorn är en viktig del av dagens samhälle och står för 20% av den totala globala energiförbrukningen. Det är också en av de sektorer med mest växthusgasutsläpp, där nästan 95% av energin härstammar från petroleumbaserade bränslen. På grund av växthusgasers potentiellt skadliga karaktär finns det ett behov för en övergång till mer hållbara transportmedel. En möjlig alternativ till den konventionella petroleumbaserade vägtransporten är implementering av elektriska vägsystem (ERS) i kombination med elfordon. Elektriska vägsystem är system som möjliggör dynamisk kraftöverföring till fordon från vägarna de kör på. Sålunda kan man genom att använda ERS i kombination med elbilar, minimera både kostnaden och vikten av batterierna samt även minska eller eliminera antalet stopp för omladdningar. Dessutom möjliggör detta system att även tunga fordon kan använda sig av batterilösningar. Det finns för närvarande i princip tre beprövade ERS-tekniker, nämligen konduktiv kraftöverföring genom luftledningar, konduktiv kraftöverföring från räls i vägen och induktiv kraftöverföring genom vägen. Syftet med denna rapport är att utvärdera och jämföra potentialen för en fullskalig implementering av dessa ERS-teknik på en global och lokal (Sverige) nivå från, framförallt, ett ekonomiskt- och ekologiskt perspektiv. Rapporten syftar också till att undersöka, med hjälp av olika scenarier, hur en utbyggnad av ERS i Sverige skulle kunna se ut fram till år 2050. För att besvara dessa frågor producerades två huvudmodeller (global och lokal perspektiv) med kompletterande undermodeller i Excel. De erhållna resultaten visar att ERS inte är lönsamt ur ett ekonomisk perspektiv i precis alla de undersökta länder, dock har ett stort antal länder i världen visat sig ha goda förutsättningar för ERS. Vidare visar resultaten att små och/eller utvecklade länder är bäst lämpade för ERS. Ur ett ekonomiskt- och ekologiskt perspektiv har konduktiv kraftöverföring från räls i väg tekniken visat sig vara den mest attraktiva, följt av konduktiv kraftöverföring genom luftledningar och induktiv kraftöverföring genom väg teknikerna. Expansionsmodellen som utvecklats visar att en snabb expansion och implementation av en ERS-baserad vägtransportsektor är det bästa alternativet, där tekniken för konduktiv kraftöverföring från räls i väg ger de största kostnadsbesparingar fram till 2050.

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