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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.
1

Energy budgeting for Thai rice agriculture

Samootsakorn, P. January 1982 (has links)
No description available.
2

Avaliação da Cogeração de Eletricidade a partir de Bagaço de Cana em Sistemas de Gaseificador a Gás / Assessment of cogeneration of electricity from bagasse in systems of biomass gasification / gas turbine

Coelho, Suani Teixeira 23 December 1992 (has links)
Antes do início do Proálcool em 1975, o primeiro programa no mundo a usar em grande escala a biomassa como combustível de veículos, as indústrias já usavam o bagaço de cana - subproduto da fabricação de açúcar e álcool - para produzir energia para uso próprio. Atualmente, além da energia térmica/elétrica para auto-suficiência da usina, é gerado também um pequeno excedente de eletricidade, vendido às concessionárias locais. Os sistemas de gaseificador/turbina a gás correspondem a tecnologias mais avançadas, em desenvolvimento, com comercialização prevista para um prazo de oito a dez anos, aproximadamente. Estes processos apresentam eficiência mais elevadas, a custo reduzido, permitindo aumentar o excedente de eletricidade gerado. Neste estudo são avaliadas as possibilidades destes sitemas de gaseificador/turbina a gás, contempladas com a projeção da eletricidade gerada até o ano 2010 em São Paulo e no Brasil. São calculados os custos de geração da eletricidade a partir do gás de bagaço, sendo obtidos resultados inferiores ao custo da eletricidade gerada com combustíveis fósseis. Também é analisada a influência da venda de excedentes de eletricidade sobre o custo de produção do álcool, para diferentes custos de oportunidades do bagaço. Os impactos ambientais e sociais são avaliados, em particular o custo do carbono evitado, em relação à substituição de combustíveis fósseis pelo bagaço de cana em usinas termoelétricas. / Digite um texto ou endereço de um site ou traduza um documento. Cancelar Tradução do português para inglês inglês português espanhol Before the start of the Alcohol Program in 1975, the first program in the world to use in large-scale biomass as fuel for vehicles, industries have used the bagasse - a byproduct of the manufacture of sugar and alcohol - to produce energy for their own use. Currently, besides the thermal energy / power for self-sufficiency of the plant, it also generated a small surplus of electricity sold to local utilities. Systems gasifier / gas turbine technologies correspond to more advanced developing countries, with marketing planned for a period of eight to ten years or so. These processes have higher efficiency, reduced cost, allowing to increase the surplus of electricity generated. In this study these possibilities are evaluated sitema gasifier / gas turbine, covered with the projection of the electricity generated by the year 2010 in Sao Paulo and Brazil. Are calculated the costs of generating electricity from gas bagasse, the result being less than the cost of electricity from fossil fuels. Also examined is the influence of the sale of surplus electricity on the cost of production of alcohol for different opportunity costs of bagasse. The environmental and social impacts are assessed, in particular the cost of carbon avoided, for the replacement of fossil fuels by sugar cane bagasse in power plants.
3

Wind energy in the built environment : an experimental and numerical investigation of a building integrated ducted wind turbine module

Dannecker, Robert Karl Walter January 2001 (has links)
Wind is now established in Europe as a major 'renewable energy' resource, but its large scale exploitation is increasingly limited by environmental issues. Hence, on the way to a more sustainable development, it is desirable to seek ways to incorporate it into small scale embedded generation. As a first step, a prototype of a small scale Ducted Wind Turbine has been developed and tested, which seems to be feasible for integration into a conventional building. The wind flow around the building generates differential pressures which may cause an enhanced massflow through the turbine. This thesis is concerned with the investigation of the flow through building integrated duct configurations. Hence, pressure and wind speed measurements have been carried out on a wind tunnel model at different angles of incident wind. Different duct geometries with attached spoilers have been tested, and it was confirmed that wind speeds up to 30 % higher than in the approaching free stream are induced in the duct, in some cases tolerating an angle of incident wind up to 60°. The experimental work proceeded in parallel with Computational Fluid Dynamics modelling. Adaptive gridding of the complex full model geometry required a two dimensional approach, which was used to compare the predicted flow behaviour qualitatively. Three dimensional simulation of the flow field in the building integrated duct could be compared with experimental results. A new flow field mapping approach was initialised to form a two stage process in which conditions in the large-scale flow domain, modelled in a coarse three dimensional simulation, are used as boundary conditions for a localised simulation of the duct flow. Based on performance measurements of a free standing prototype in field trials and the experimentally determined wind speed in the duct, a power prediction model was developed. For the Scottish climate, the proposed device compares favorably with conventional small wind turbines and photovoltaics. The presented work evaluates the concept of harvesting wind energy in the built environment and provides outlines for the future design of a building integrated Ducted Wind Turbine module.
4

Avaliação da Cogeração de Eletricidade a partir de Bagaço de Cana em Sistemas de Gaseificador a Gás / Assessment of cogeneration of electricity from bagasse in systems of biomass gasification / gas turbine

Suani Teixeira Coelho 23 December 1992 (has links)
Antes do início do Proálcool em 1975, o primeiro programa no mundo a usar em grande escala a biomassa como combustível de veículos, as indústrias já usavam o bagaço de cana - subproduto da fabricação de açúcar e álcool - para produzir energia para uso próprio. Atualmente, além da energia térmica/elétrica para auto-suficiência da usina, é gerado também um pequeno excedente de eletricidade, vendido às concessionárias locais. Os sistemas de gaseificador/turbina a gás correspondem a tecnologias mais avançadas, em desenvolvimento, com comercialização prevista para um prazo de oito a dez anos, aproximadamente. Estes processos apresentam eficiência mais elevadas, a custo reduzido, permitindo aumentar o excedente de eletricidade gerado. Neste estudo são avaliadas as possibilidades destes sitemas de gaseificador/turbina a gás, contempladas com a projeção da eletricidade gerada até o ano 2010 em São Paulo e no Brasil. São calculados os custos de geração da eletricidade a partir do gás de bagaço, sendo obtidos resultados inferiores ao custo da eletricidade gerada com combustíveis fósseis. Também é analisada a influência da venda de excedentes de eletricidade sobre o custo de produção do álcool, para diferentes custos de oportunidades do bagaço. Os impactos ambientais e sociais são avaliados, em particular o custo do carbono evitado, em relação à substituição de combustíveis fósseis pelo bagaço de cana em usinas termoelétricas. / Digite um texto ou endereço de um site ou traduza um documento. Cancelar Tradução do português para inglês inglês português espanhol Before the start of the Alcohol Program in 1975, the first program in the world to use in large-scale biomass as fuel for vehicles, industries have used the bagasse - a byproduct of the manufacture of sugar and alcohol - to produce energy for their own use. Currently, besides the thermal energy / power for self-sufficiency of the plant, it also generated a small surplus of electricity sold to local utilities. Systems gasifier / gas turbine technologies correspond to more advanced developing countries, with marketing planned for a period of eight to ten years or so. These processes have higher efficiency, reduced cost, allowing to increase the surplus of electricity generated. In this study these possibilities are evaluated sitema gasifier / gas turbine, covered with the projection of the electricity generated by the year 2010 in Sao Paulo and Brazil. Are calculated the costs of generating electricity from gas bagasse, the result being less than the cost of electricity from fossil fuels. Also examined is the influence of the sale of surplus electricity on the cost of production of alcohol for different opportunity costs of bagasse. The environmental and social impacts are assessed, in particular the cost of carbon avoided, for the replacement of fossil fuels by sugar cane bagasse in power plants.
5

Public perceptions of wave energy on the Oregon coast /

Hunter, Daniel A. January 1900 (has links)
Thesis (M.A.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 164-169). Also available on the World Wide Web.
6

Modelo de cômputo e valoração de potenciais completos de recursos energéticos para o planejamento integrado de recursos. / Model for the accouting and valuation of energy resources full potentials within the integrated resource planning.

Baitelo, Ricardo Lacerda 15 December 2010 (has links)
Esta tese apresenta a metodologia de cômputo e valoração de potenciais completos de recursos energéticos no âmbito do Planejamento Integrado de Recursos. A metodologia é genérica a diferentes tipos de recursos dos lados de oferta e demanda - e flexível a fim de permitir sua aplicação em diferentes regiões. A etapa de cômputo e valoração de potenciais é de suma importância no processo de planejamento integrado de recursos e sua metodologia consiste na transformação de informações prévias relativas às dimensões de análise em potenciais completos. Para tanto, são confeccionados algoritmos de cômputo e valoração, capazes de converter o conteúdo qualitativo ou relativo de cada atributo em valores absolutos ou diagnósticos quantitativos. Estes potenciais alimentam as etapas subsequentes do PIR tais como o Ranqueamento de Recursos e o Plano Preferencial Integrado de Recursos. O Planejamento Integrado de Recursos Energéticos é, por natureza, uma metodologia de análise de implementação de recursos energéticos com base em seus potenciais holísticos, de acordo com variáveis espaciais e temporais. Para tanto, a metodologia do PIR parte de um conjunto de recursos energéticos disponíveis e aponta dentre estes quais devem ser preferencialmente aproveitados em um dado cenário, de modo a orientar a busca pela satisfação das necessidades energéticas dos diversos atores envolvidos. Esta implantação de recursos pode tanto ser regulamentada ou induzida pela atração de investimentos e políticas públicas. O PIR diferencia-se do planejamento energético tradicional no que se refere à atenção dada a recursos do lado da demanda como alternativas factíveis de atendimento à demanda energética ao lado das opções do lado da oferta -, e à ponderação equilibrada da análise destes recursos sob óticas sociais, ambientais e políticas, ao lado de parâmetros técnicos e econômicos. Esta análise holística insere em cada dimensão os diversos aspectos dos impactos associados a cada recurso energético, ou seja, busca contabilizar tanto os custos internos e tangíveis de empreendimentos energéticos, quanto custos externos marginalizados de análises técnico-econômicas. A metodologia de cômputo e valoração de recursos energéticos é validada em Estudo de Caso com base em informações colhidas na Região Administrativa de Araçatuba. Quatro recursos energéticos foram escolhidos para o estudo de caso: pequenas centrais hidrelétricas e sistemas de cogeração a biomassa do lado da oferta e a implantação de sistemas de aquecimento solar de água e a substituição de lâmpadas incandescentes por iluminação fluorescente do lado da demanda. Toda a informação referente a esses recursos foi processada pelos algoritmos de valoração e resultou em potenciais completos nas quatro dimensões de análise, dispostos em matrizes de valoração. Estas matrizes alimentarão as etapas subsequentes do planejamento integrado de recursos - os processos de ranqueamento de recursos e formulação de plano preferencial integrado de recursos. / This thesis presents a methodology for the accounting and valuation of energy resources full potentials, within the Integrated Resource Planning (IRP). The methodology is generic to different types of resources in both supply and demand sides and flexible as to allow its application in different regions. The calculation and assessment of potentials is of paramount importance in the energy planning process and its methodology consists of converting preliminary information from all areas of analysis into full potentials. For this purpose, algorithms are designed to convert the qualitative content of each attribute in figures or quantifiable diagnostics. These potentials fuel the subsequent steps of the IRP - such as the resource ranking and the Integrated Preferential Plan. The Integrated Resources Planning is by nature a methodology for the assessment of energy resources based on their holistic potential, according to space and time variables. Therefore, the IRP methodology starts from a set of available energy resources and among these indicates the ones which should preferably be utilized in a given scenario in order to guide the demands of different involved stakeholders. The deployment of resources can be either regulated or induced by public policies and investment attraction. The IRP differs from traditional energy planning with regard to attention given to demand-side resources as feasible alternatives energy to meet energy demand - along the options on the supply side - and the balanced consideration of the analysis of these resources through a social, environmental and political lens, alongside technical and economic parameters. This holistic analysis inserts in each dimension the various aspects of the impacts associated with each energy resource, that is, seeks to account both tangible and internal costs of energy enterprises and the external costs marginalized from technical-economic analysis. The method for the calculation and valuation of energy resources is validated by a case study based on information collected in the Administrative Region of Araçatuba in the state of São Paulo. Four energy resources were chosen in the case study: small hydro plants and sugarcane biomass cogeneration on the supply side and installation of solar heating and replacement of incandescent lighting for fluorescent lamps on the demand side. All the data concerning these resources was processed by the valuation algorithms and resulted in full potentials in all four analysis dimensions, displayed in valuation matrixes. These matrixes will be able to feed the subsequent steps of the integrated resources planning - the processes of resource ranking and the formulation of the integrated preferential plan.
7

Modelo de cômputo e valoração de potenciais completos de recursos energéticos para o planejamento integrado de recursos. / Model for the accouting and valuation of energy resources full potentials within the integrated resource planning.

Ricardo Lacerda Baitelo 15 December 2010 (has links)
Esta tese apresenta a metodologia de cômputo e valoração de potenciais completos de recursos energéticos no âmbito do Planejamento Integrado de Recursos. A metodologia é genérica a diferentes tipos de recursos dos lados de oferta e demanda - e flexível a fim de permitir sua aplicação em diferentes regiões. A etapa de cômputo e valoração de potenciais é de suma importância no processo de planejamento integrado de recursos e sua metodologia consiste na transformação de informações prévias relativas às dimensões de análise em potenciais completos. Para tanto, são confeccionados algoritmos de cômputo e valoração, capazes de converter o conteúdo qualitativo ou relativo de cada atributo em valores absolutos ou diagnósticos quantitativos. Estes potenciais alimentam as etapas subsequentes do PIR tais como o Ranqueamento de Recursos e o Plano Preferencial Integrado de Recursos. O Planejamento Integrado de Recursos Energéticos é, por natureza, uma metodologia de análise de implementação de recursos energéticos com base em seus potenciais holísticos, de acordo com variáveis espaciais e temporais. Para tanto, a metodologia do PIR parte de um conjunto de recursos energéticos disponíveis e aponta dentre estes quais devem ser preferencialmente aproveitados em um dado cenário, de modo a orientar a busca pela satisfação das necessidades energéticas dos diversos atores envolvidos. Esta implantação de recursos pode tanto ser regulamentada ou induzida pela atração de investimentos e políticas públicas. O PIR diferencia-se do planejamento energético tradicional no que se refere à atenção dada a recursos do lado da demanda como alternativas factíveis de atendimento à demanda energética ao lado das opções do lado da oferta -, e à ponderação equilibrada da análise destes recursos sob óticas sociais, ambientais e políticas, ao lado de parâmetros técnicos e econômicos. Esta análise holística insere em cada dimensão os diversos aspectos dos impactos associados a cada recurso energético, ou seja, busca contabilizar tanto os custos internos e tangíveis de empreendimentos energéticos, quanto custos externos marginalizados de análises técnico-econômicas. A metodologia de cômputo e valoração de recursos energéticos é validada em Estudo de Caso com base em informações colhidas na Região Administrativa de Araçatuba. Quatro recursos energéticos foram escolhidos para o estudo de caso: pequenas centrais hidrelétricas e sistemas de cogeração a biomassa do lado da oferta e a implantação de sistemas de aquecimento solar de água e a substituição de lâmpadas incandescentes por iluminação fluorescente do lado da demanda. Toda a informação referente a esses recursos foi processada pelos algoritmos de valoração e resultou em potenciais completos nas quatro dimensões de análise, dispostos em matrizes de valoração. Estas matrizes alimentarão as etapas subsequentes do planejamento integrado de recursos - os processos de ranqueamento de recursos e formulação de plano preferencial integrado de recursos. / This thesis presents a methodology for the accounting and valuation of energy resources full potentials, within the Integrated Resource Planning (IRP). The methodology is generic to different types of resources in both supply and demand sides and flexible as to allow its application in different regions. The calculation and assessment of potentials is of paramount importance in the energy planning process and its methodology consists of converting preliminary information from all areas of analysis into full potentials. For this purpose, algorithms are designed to convert the qualitative content of each attribute in figures or quantifiable diagnostics. These potentials fuel the subsequent steps of the IRP - such as the resource ranking and the Integrated Preferential Plan. The Integrated Resources Planning is by nature a methodology for the assessment of energy resources based on their holistic potential, according to space and time variables. Therefore, the IRP methodology starts from a set of available energy resources and among these indicates the ones which should preferably be utilized in a given scenario in order to guide the demands of different involved stakeholders. The deployment of resources can be either regulated or induced by public policies and investment attraction. The IRP differs from traditional energy planning with regard to attention given to demand-side resources as feasible alternatives energy to meet energy demand - along the options on the supply side - and the balanced consideration of the analysis of these resources through a social, environmental and political lens, alongside technical and economic parameters. This holistic analysis inserts in each dimension the various aspects of the impacts associated with each energy resource, that is, seeks to account both tangible and internal costs of energy enterprises and the external costs marginalized from technical-economic analysis. The method for the calculation and valuation of energy resources is validated by a case study based on information collected in the Administrative Region of Araçatuba in the state of São Paulo. Four energy resources were chosen in the case study: small hydro plants and sugarcane biomass cogeneration on the supply side and installation of solar heating and replacement of incandescent lighting for fluorescent lamps on the demand side. All the data concerning these resources was processed by the valuation algorithms and resulted in full potentials in all four analysis dimensions, displayed in valuation matrixes. These matrixes will be able to feed the subsequent steps of the integrated resources planning - the processes of resource ranking and the formulation of the integrated preferential plan.
8

Ocean electric energy extraction opportunities /

Zhang, Heng. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2004. / Printout. Includes bibliographical references (leaf 47). Also available online.
9

The impact of large scale wave energy converter farms on the regional wave climate

Greenwood, Charles January 2016 (has links)
No description available.
10

An economic analysis of concentrator photovoltaic technology use in South Africa: a case study

Beukes, Justin January 2013 (has links)
South Africa relies heavily on fossil fuels, particularly coal, to generate electricity and it is a well known fact that the use of fossil fuels contributes to climate change, as it produces greenhouse gases (GHGs). In fact, internationally South Africa is the 17th highest emitter of GHGs (Congressional Research Service (CRS), 2008). Coupled with the environmental consequences of fossil fuel use, South Africa has a further responsibility of addressing the inherited backlog of electricity provision to the rural, and previously disadvantaged communities. In an attempt to address these two problems, the government issued the White Paper on Renewable Energy. In this paper, renewable energy alternatives are proposed to replace a portion of traditional electricity generating methods. Concentrator photovoltaic (CPV) energy generation is one such renewable option available to government. CPV uses optic elements (such as lenses) to concentrate sunlight onto solar cells. Owing to the light being concentrated, the cells in CPV use less semiconductor material, which makes them more efficient in comparison to conventional photovoltaic (PV) cells. CPV is a technology that operates well in regions with high solar radiation. As such, South Africa is particularly well suited for this technology, with average solar radiation levels ranging from 4.5 to 6.5 05 ℎ/. CPV is also well suited for off-grid application, which addresses electricity demand in remote rural areas. This study is an economic project analysis of the installation, operation, maintenance, and decommissioning of CPV technology in a rural area in the Eastern Cape, South Africa. The study area chosen for this purpose is the Tyefu settlement in the Eastern Cape. Tyefu was deemed ideal for this type of analysis due to four characteristics. Firstly, Tyefu is a remote rural settlement at the end of the national grid. Secondly, the community is very poor and previously disadvantaged. Thirdly, many households are without Eskom generated electricity. Lastly, the study area is located in an area with ideal irradiance levels for CPV. Two methods of economic project analysis are applied to this case study, namely a costbenefit analysis (CBA) and a cost-effectiveness analysis (CEA). Additionally, two types of CBA are performed, namely a private CBA and a social CBA. The private CBA evaluates the Tyefu electrification project from a private investor's perspective and the social CBA evaluates the project from society's point of view. The CEAs carried out compare the costeffectiveness of the traditional PV technology to that of CPV in terms of private and social costs. The private costs and benefits of the CPV project were identified and valued in terms of market prices. Then, this cost benefit profile was used to calculate net benefits which in turn were discounted to present values using a private discount rate of 6.42 percent. Three decision making criteria were generated, namely the net present value (NPV), the internal rate of return (IRR) and the benefit cost ratio (BCR). Sensitivity analysis was carried out by varying the private discount rate and the bidding price. The social costs and benefits of the CPV project were identified and valued in terms of shadow prices. This cost benefit profile was used to calculate net benefits. The net benefits were discounted to present values using a composite social discount rate equal to 5.97 percent. The same decision making criteria used in the private CBA were used in the social CBA and a sensitivity analysis was completed by varying the social discount rate. In terms of the private CEA, the costs were identified and valued in terms of market prices. All costs were brought to present values using the private discount rate of 6.42 percent. In terms of the social CEA, the costs were identified and valued in terms of shadow prices. All costs were brought to present values using the social discount rate of 5.97 percent. The cost-effectiveness (CE) ratios calculated have identical denominators since the annual output for both technologies are identical - both CPV and PV systems deliver 30 300 kWh per annum. This output is based on the demand of the given case study. The private CBA showed unfavourable results. The private CBA has a NPV of R2 046 629.01, the IRR is undefined (this is due to no sign change being present in the cost benefit profile), and has a BCR of 0.365. However, the social CBA yielded positive results, with a NPV of R125 616.64, an IRR of 8 percent (which exceeds the social discount rate of 5.97 percent), and a BCR of 1.045. The CEA showed that the CPV is more cost-effective than the traditional PV both in terms of private and social costs. The private CE ratio of CPV is R4.23/kWh compared to PV's CE ratio of R4.39/kWh. Similarly, the social CE ratio of CPV is R3.51/kWh compared to PV's CE ratio of R3.69/kWh. CPV rollout appears to be socially efficient on a small scale according to the social CBA. Consequently, the CPV project is not seen as desirable in terms of the private CBA as the benefit (income received per kWh) in the private analysis is too small to outweigh the costs of implementing and running a CPV plant in Tyefu. On the other hand, a redeeming factor is that CPV may be feasible privately, for large scale applications. A major reason for the CPV project not being appealing to private investors is that the maximum bidding price of R2.85/kWh (as at August 2011) is not high enough for private investors to undertake the CPV project. The sensitivity analysis of the bidding price showed that the bidding price of R2.85/kWh needs to be increased in the range of 250 percent (R7.13/kWh) and 300 percent (R8.55/kWh) for a great enough incentive to exist for private investors. It is thus recommended that policymakers take this into consideration when formulating policy. In terms of the social CBA, it is recommended that government undertake CPV projects of this kind, as it will be a socially desirable allocation of resources. If government were to pursue these types of projects, it is recommended that CPV be implemented as it is more cost effective than PV.

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