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Analysis of the effect of renewable generation on the power quality of the grid, modelling and analysis of harmonic and voltage distortionMusoni, Nkusi Emmanuel January 2018 (has links)
Thesis (Master of Engineering in Electrical Engineering)--Cape Peninsula University of Technology, 2018. / As the electric energy demand grows, there is a significant increase in the penetration of renewable generation (RG) in the existing electrical grid network. Interconnecting of renewable generation technologies to an existing distribution system has proven to provide various benefits such as meeting the growing load demand and its contribution to energy system decarbonisation, long-term energy security and expansion of energy access to new energy consumers in the developing urban and rural areas. However, the aim of this thesis is to conduct a study on the impacts of renewable generation on the power quality of electrical grid. Therefore, this work aims at assessing the potential effects of Distributed Generation (DG) on the operation of electric power system by modelling of harmonics and voltage distortion. With different types of renewable generation available at present, it is believed that some designs contribute significantly to electrical network’s Power Quality (PQ). After the analysis of harmonic currents (chapter 6 and 7 of this thesis) introduced by renewable generation technologies, their negative impact on the power quality of the grid is seen to be apparent at point of connection (POC) but only within controlled limits. Analytical method for modeling of harmonic interactions between the grid and aggregated distributed generation technologies are investigated using DIgSILENT Power Factory software and the results obtained are discussed.
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Komplexní posouzení energetické náročnosti výroby granulí pro vytápění z obnovitelných zdrojů / Comprehensive Assessment of Energy Demand in Production of Granules for Renewable Resources HeatingSTERNBERG, Jiří January 2015 (has links)
The first part of the graduation thesis deals with renewable resources, utilization possibilities of biomass and plant phytomass. The most common sources from which phytomass is obtained, are also mentioned here. A great deal of attention is paid to selected energetic plants included into the experiment. It is Sorrel Rumex OK-2 (Rumex tianschanicus x Rumex patientia) and Poppy seed (Papaver Somniferum). Further there are summarized the processes necessary for separating and pressing of biomass into granules for direct combustion. Within the research, two-year experience of growing sorrel stand is described. On the basis of performed technological operations in the stand, energy demands of growing are calculated. The real usage of energy at the production of one tonne of granules is measured. When labour costs are taken into account I can say that the expenses for the production of one tonne of briquettes from biomass would be 4 592 CZK, which is a non-competitive sum.
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Let Wind Rise – Harnessing Bulk Energy Storage under Increasing Renewable Penetration LevelsJanuary 2016 (has links)
abstract: With growing concern regarding environmental issues and the need for a more sustainable grid, power systems have seen a fast expansion of renewable resources in the last decade. The uncertainty and variability of renewable resources has posed new challenges on system operators. Due to its energy-shifting and fast-ramping capabilities, energy storage (ES) has been considered as an attractive solution to alleviate the increased renewable uncertainty and variability.
In this dissertation, stochastic optimization is utilized to evaluate the benefit of bulk energy storage to facilitate the integration of high levels of renewable resources in transmission systems. A cost-benefit analysis is performed to study the cost-effectiveness of energy storage. A two-step approach is developed to analyze the effectiveness of using energy storage to provide ancillary services. Results show that as renewable penetrations increase, energy storage can effectively compensate for the variability and uncertainty in renewable energy and has increasing benefits to the system.
With increased renewable penetrations, enhanced dispatch models are needed to efficiently operate energy storage. As existing approaches do not fully utilize the flexibility of energy storage, two approaches are developed in this dissertation to improve the operational strategy of energy storage. The first approach is developed using stochastic programming techniques. A stochastic unit commitment (UC) is solved to obtain schedules for energy storage with different renewable scenarios. Operating policies are then constructed using the solutions from the stochastic UC to efficiently operate energy storage across multiple time periods. The second approach is a policy function approach. By incorporating an offline analysis stage prior to the actual operating stage, the patterns between the system operating conditions and the optimal actions for energy storage are identified using a data mining model. The obtained data mining model is then used in real-time to provide enhancement to a deterministic economic dispatch model and improve the utilization of energy storage. Results show that the policy function approach outperforms a traditional approach where a schedule determined and fixed at a prior look-ahead stage is used. The policy function approach is also shown to have minimal added computational difficulty to the real-time market. / Dissertation/Thesis / Doctoral Dissertation Engineering 2016
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Hodnocení investičního projektu - výstavba fotovoltaické elektrárny / Investment evaluation - Building of photovoltaic power plantKosinová, Michaela January 2008 (has links)
The thesis deals with the following question: 1. What are the renewable resources? 2. Types of renewable resource. 3. European Union approach to renewable resources: targets 4. Czech Republic approach to renewable resources: targets 5. Investment evaluation: Photovoltaic power plant.
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Specifika výstavby a provozu bioplynových zemědělských stanic včetně posouzení jejich ekonomické efektivnosti z hlediska stávající dotační, subvenční a pobídkové politiky v oblasti obnovitelných zdrojů energie / The Specifics of the Construction and Operation of Agricultural Biogas StationsChládek, Ivo January 2012 (has links)
The subject of this thesis is precisely what one sentence he says her name - the specifics of the construction and operation of agricultural biogas plants ( BPZS ) including assessment of their economic efficiency in terms of the existing subsidy , subsidy and incentive policies for renewable energy sources ( RES) . The site -specific construction and operation in the detail reports for this purpose specially modified documents business plan - feasibility and economic audit. Economic efficiency of the existing subsidy , subsidy and incentive policy examines modern fundamental financial analysis projects based APV ( taking into account the effects of special financing details of the NPV) . Based on its findings the conclusion of the practical part of the thesis formulated specific recommendations that can effectively contribute to the suppression of the feared consequences of the expected boom BPZS development in the country.
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Synthesis and characterization of lactic acid-based elastomersMakhdoumi, Afsaneh January 2023 (has links)
Synthesized polymer from bio-based and renewable resources reported as an attractive substitution for fossil-fuel based polymers. Therefore, this work has focused on using sustainable material for production of elastomers to reduce the environmental impact of fossil-based elastomers and overcome the shortage of non-renewable fuels. In this research (as thesis work) bio-based elastomers (resins synthesized by reacting of lactic acid with 1,4-butanediol in presence of toluene and methanesulfonic acid as solvent and catalyst, respectively. To trace the reaction, the Fourier transform infrared (FT-IR) spectrometer was used for structural characterization of the products. Furthermore, the degree of reaction followed by measuring of the acid value using alkali titration method. To achieve the desirable results, both condensed resins were reacted with caprolactone for ring opening polymerization. The produced resins were finally functionalized using methacrylic anhydride and the structures and thermal properties of the produced resin were characterized using FT-IR, DSC and TGA. In addition, the viscoelastic properties of the resins were investigated using dynamic mechanical analysis (DMA); and elasticity and viscosity of the elastomers measured using tensile testing machine and viscometer, respectively. The important result such as viscosity showed the resin with chain length n= 5 had higher viscosity when compared to the resin chain length n=3. This makes the resin (n=5) suitable for applications that need high viscosities. The resin with chain length n=3 had lower viscosity that is suitable for processing at room temperature. Furthermore, the tensile strength results show maximum elongation for resin with chain length n=3 is almost double compared to resin with chain length n=5. The results showed that these bio-based resins are compatible with petrochemical-based resins, due to desirable rubbery properties, melting temperature, also acceptable viscosity, and other good mechanical properties as will be mentioned below.
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Análise do efeito em termos de desempenho ambiental da substituição de eteno de origem fóssil por equivalente renovável na produção de poliestireno. / Assessment of the environmental performance effects associated with the replacement of ethylene from fossil by renewable resource in the polystyrene production.Hansen, Adriana Petrella 27 June 2013 (has links)
O uso intensivo de petróleo tem sido matéria de discussões constantes por diferentes setores da sociedade, seja pela possibilidade de seu esgotamento ou pelos potenciais danos ambientais por ele ocasionados. Assim, com o intuito de minimizar os impactos gerados na produção de bens de consumo fundamentalmente constituídos por recursos fósseis, a indústria petroquímica se mobilizou no desenvolvimento de novas tecnologias. No que tange a produção de derivados poliméricos, a principal estratégia adotada nesse sentido está associada à substituição de petróleo por insumos manufaturados a partir de fontes renováveis. Esta solução visa tanto reduzir a extração dos recursos fósseis, quanto amenizar as emissões de gases efeito estufa. Entretanto, poucos são os estudos que avaliam os reais efeitos decorrentes desta medida, quantificando os impactos, positivos e negativos, ocasionados ao meio ambiente e ao homem. Diante deste fato, o presente trabalho tem por finalidade investigar os efeitos ambientais da substituição de eteno de origem fóssil por sucedâneo obtido via desidratação de etanol de cana-de-açúcar, no processo produtivo do poliestireno. O atendimento de tal objetivo foi alcançado a partir da aplicação da técnica de Avaliação do Ciclo de Vida (ACV), cuja visão sistêmica permite analisar a influência da troca de matérias- primas para a produção de uma tonelada de poliestireno cristal (GPPS) e uma tonelada de poliestireno de alto impacto (HIPS), respectivamente. A abordagem possui uma abrangência do berço-ao-portão da fábrica e faz uso do método de avaliação ReCiPe (H) Midpoint, versão 1.07. Considerando treze categorias de impacto, os resultados dos perfis de desempenho do GPPS e HIPS parcialmente renováveis apresentaram-se pior em: mudanças climáticas; acidificação terrestre; eutrofização; toxicidade humana; formação de oxidantes fotoquímicos e material particulado; ecotoxicidade terrestre e aquática; uso de solo agricultável e depleção de água; em resposta às atividades agrícolas para a produção de cana-de-açúcar. Por outro lado, os maiores consumos de gás natural e petróleo requeridos para a manufatura de eteno no sistema de produto do GPPS e HIPS fósseis, contribuíram para impactos relativamente superiores nas categorias de depleção de ozônio, transformação de solo natural e depleção de recursos fósseis. / The intensive use of oil has been a subject of constant discussion among different sectors of society, due to the fossil depletion and potential environmental damage caused by it. Therefore, in order to minimize impacts on the production of consumer goods made from fossil resources, the petrochemical industry has been developing new technologies. Regarding the production of polymer derivatives, the key strategy was to replace fossil assets by raw materials obtained from renewable resources, for the purpose of slowing down the extraction of crude oil, as well as balancing atmospheric emission of greenhouse gases. However, there are only few studies assessing the actual results of this solution, quantifying its positive and negative environmental impacts. Considering this scenario, this study aims to investigate the environmental effects associated to the replacement of ethylene produced from natural gas by ethylene obtained by sugarcane ethanol dehydration in the production of polystyrene. This study used the Life Cycle Assessment (LCA) methodology, which systemic view allows to analyze the influence of this substitution during the production of one ton of crystal polystyrene (GPPS) and one ton of high impact polystyrene (HIPS). The system boundary comprises a \"cradle-to-gate\" approach and uses ReCiPe Midpoint (H) V1.07 method to analyze thirteen environmental impacts. Both GPPS and HIPS partially made from renewable resource presented unfavorable results in ten impacts categories: climate change, terrestrial acidification, eutrophication, human toxicity, photochemical oxidants formation, particulate matter formation, terrestrial and freshwater Ecotoxicity, agricultural land occupation and water depletion. This scenario can be assigned to sugarcane production activities. On the other hand, the higher consumption of natural gas and crude oil required for the manufacture of ethylene in the fossil GPPS and HIPS system boundary contributed to greater impacts in the categories of ozone depletion, natural land transformation and fossil depletion.
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Bioekonomika: teorinis ir taikomasis požiūriai / Bioeconomy: A Theoretical And Applied ApproachKniūkšta, Bernardas 14 January 2009 (has links)
Tyrimo objektas – bioekonomikos teorinis turinys ir taikomosios sritys. Darbo tikslas – atskleisti bioekonomikos teorinį turinį ir nustatyti jos apimamas ekonominės veiklos sritis, išryškinant jos sąsajas su darniu vystymusi. Uždaviniai: 1) atskleisti bioekonomikos koncepcijas ir traktuotes; 2) išanalizuoti bioekonomikos vaidmenį ekonomikoje, teikiamą naudą ir keliamą riziką; 3) atskleisti bioekonomikos indėlį į darnų vystymąsi; 4) nustatyti bioekonomikos vystymosi prielaidas. Tyrimo metodai - analizuojant bioekonomikos teorinius aspektus - jos traktuotę bei sankirtą su kitais mokslais - naudoti apibendrinimo ir apibendrinamosios abstrakcijos metodai; analizuojant bioekonomikos vaidmenį pasaulio ekonomikoje, jos teikiamą naudą ir iššaukiamą riziką taikytas loginės analizės metodas; bioekonomikos indėlis į darnų vystymąsi nagrinėtas izoliuojančiosios abstrakcijos metodu; analizuojant tarptautinių institucijų ir Lietuvos požiūrį į bioekonomiką naudoti akademinės, teisinės ir mokslo populiarinimo literatūros bendramoksliniai tyrimo metodai – loginė analizė ir sintezė bei dokumentų analizės metodai. Literatūros ir informacijos šaltinai – Lietuvos ir užsienio mokslininkų darbai, konferencijų medžiaga, tarptautinių institucijų dokumentai, teisės aktai. / Research object – theoretical content and applied fields in bioeconomy. Research aim – to reveal content of bioeconomics, to identify range of economic activities involved in bioeconomy and highlight its connections with sustainable development. Objectives: 1) to reveal approaches and conceptions of bioeconomy; 2) to analyse the role of bioeconomy in the world economy including its advantage and disadvantage; 3) to define contribution of bioeconomy to sustainable development; 4) to define premises of bioeconomy development. Research methods: in the analysis of theoretical aspects of bioeconomy and its interaction with related sciences was applied generalization method; in the analysis of the role of bioeconomy in the world economy including its advantage and disadvantage was applied logical analysis method; in the analysis of contribution of bioeconomy to sustainable development was applied abstraction method; in analysis of attitudes towards bioeconomy were applied analysis and synthesis of scientific literature and international organization documents. References and information: publications of foreign scientists, conference materials, documents of international institutions and legal acts.
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Análise do efeito em termos de desempenho ambiental da substituição de eteno de origem fóssil por equivalente renovável na produção de poliestireno. / Assessment of the environmental performance effects associated with the replacement of ethylene from fossil by renewable resource in the polystyrene production.Adriana Petrella Hansen 27 June 2013 (has links)
O uso intensivo de petróleo tem sido matéria de discussões constantes por diferentes setores da sociedade, seja pela possibilidade de seu esgotamento ou pelos potenciais danos ambientais por ele ocasionados. Assim, com o intuito de minimizar os impactos gerados na produção de bens de consumo fundamentalmente constituídos por recursos fósseis, a indústria petroquímica se mobilizou no desenvolvimento de novas tecnologias. No que tange a produção de derivados poliméricos, a principal estratégia adotada nesse sentido está associada à substituição de petróleo por insumos manufaturados a partir de fontes renováveis. Esta solução visa tanto reduzir a extração dos recursos fósseis, quanto amenizar as emissões de gases efeito estufa. Entretanto, poucos são os estudos que avaliam os reais efeitos decorrentes desta medida, quantificando os impactos, positivos e negativos, ocasionados ao meio ambiente e ao homem. Diante deste fato, o presente trabalho tem por finalidade investigar os efeitos ambientais da substituição de eteno de origem fóssil por sucedâneo obtido via desidratação de etanol de cana-de-açúcar, no processo produtivo do poliestireno. O atendimento de tal objetivo foi alcançado a partir da aplicação da técnica de Avaliação do Ciclo de Vida (ACV), cuja visão sistêmica permite analisar a influência da troca de matérias- primas para a produção de uma tonelada de poliestireno cristal (GPPS) e uma tonelada de poliestireno de alto impacto (HIPS), respectivamente. A abordagem possui uma abrangência do berço-ao-portão da fábrica e faz uso do método de avaliação ReCiPe (H) Midpoint, versão 1.07. Considerando treze categorias de impacto, os resultados dos perfis de desempenho do GPPS e HIPS parcialmente renováveis apresentaram-se pior em: mudanças climáticas; acidificação terrestre; eutrofização; toxicidade humana; formação de oxidantes fotoquímicos e material particulado; ecotoxicidade terrestre e aquática; uso de solo agricultável e depleção de água; em resposta às atividades agrícolas para a produção de cana-de-açúcar. Por outro lado, os maiores consumos de gás natural e petróleo requeridos para a manufatura de eteno no sistema de produto do GPPS e HIPS fósseis, contribuíram para impactos relativamente superiores nas categorias de depleção de ozônio, transformação de solo natural e depleção de recursos fósseis. / The intensive use of oil has been a subject of constant discussion among different sectors of society, due to the fossil depletion and potential environmental damage caused by it. Therefore, in order to minimize impacts on the production of consumer goods made from fossil resources, the petrochemical industry has been developing new technologies. Regarding the production of polymer derivatives, the key strategy was to replace fossil assets by raw materials obtained from renewable resources, for the purpose of slowing down the extraction of crude oil, as well as balancing atmospheric emission of greenhouse gases. However, there are only few studies assessing the actual results of this solution, quantifying its positive and negative environmental impacts. Considering this scenario, this study aims to investigate the environmental effects associated to the replacement of ethylene produced from natural gas by ethylene obtained by sugarcane ethanol dehydration in the production of polystyrene. This study used the Life Cycle Assessment (LCA) methodology, which systemic view allows to analyze the influence of this substitution during the production of one ton of crystal polystyrene (GPPS) and one ton of high impact polystyrene (HIPS). The system boundary comprises a \"cradle-to-gate\" approach and uses ReCiPe Midpoint (H) V1.07 method to analyze thirteen environmental impacts. Both GPPS and HIPS partially made from renewable resource presented unfavorable results in ten impacts categories: climate change, terrestrial acidification, eutrophication, human toxicity, photochemical oxidants formation, particulate matter formation, terrestrial and freshwater Ecotoxicity, agricultural land occupation and water depletion. This scenario can be assigned to sugarcane production activities. On the other hand, the higher consumption of natural gas and crude oil required for the manufacture of ethylene in the fossil GPPS and HIPS system boundary contributed to greater impacts in the categories of ozone depletion, natural land transformation and fossil depletion.
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Evaluation and Selection of Renewable Energy Technologies for Highway Maintenance FacilitiesAndrews, Taylor January 2013 (has links)
No description available.
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