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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.
51

Bring Light to Gaza. An exploration of solar and ecologically-sensitive light programs for the Deir al-Balah refugee camp

Benouaich, Abigail January 2020 (has links)
In Gaza, daily blackouts have lasted for over eleven years. Until recently, Palestinian families have received only four hours of power each day. Since Israel’s withdrawal from the region in 2005, the political discourse around the Right of Return has forced refugees to live in terrible conditions and darkness. The fear was that any transformation of the camps will bring about an integration of the refugee community with the local environment and thus any improvements to Gaza’s infrastructure and housing was seen as a direct erosion of the Right of Return. Can bringing light to Gaza transcend this boundary of temporality and restore hope to this impoverished community? With recent solar lighting ideas emerging to help solve Gaza’s energy shortage by solar energy companies such as SunBox and LittleSun, I plan to develop a solar urban lighting project for Gaza’s smallest refugee camp - Deir al-Balah (DEB) - to help improve security at night for residents and provide the community with opportunities to socialise in public common areas. In response to an ‘Improvement Plan’ conducted by the United Nations Relief and Works Agency (UNRWA) in 2017, which identifies DEB camp’s limited access to electricity and street lighting, I’d like to explore how a solar and ecologically-sensitive lighting programs can improve Gazan’s daily lives, by bringing clean, reliable and affordable energy access.
52

Performance Characteristics of an Innovative Wind Power System

Kerze, David James January 2007 (has links)
No description available.
53

An Integrated Closed Convergent System for Optimal Extraction of Head-Driven Tidal Energy

Vieira, Michelle Ann 01 January 2018 (has links)
As the demands for energy increased with the global increase in population, there is a need to create and invest in more clean and renewable energy sources. Energy derived from the movement of the tides is an ancient concept that is currently being harnessed in a handful of large tidal range locations. However, the need to move from fossil fuel driven energy sources to those that are clean and non-polluting is a priority for a sustainable future. Globally, hydropower potential is estimated to be more than 16,400-Terawatt hours annually. Given that the electricity consumption worldwide was at 15,068-Terawatt hours in 2016, if properly utilized, hydropower could supply a substantial percentage of current demand. Most of the current hydropower supply is drawn from well-established dams and tidal barrage systems. However, tidal power plants that harness the change in water height and flow along the coast (i.e. using tidal energy) have the potential to push these figures even higher. Although there is no exact number for lengths of global coastlines, there are estimates that put that number between 220,000 and 880,000 miles of coasts. These opportunities in tidal energy technologies that harness energy from the sea may one day be the key to solving our energy crises. This research explored in detail a closed, convergent system for optimal extraction of head-driven tidal energy with minimal adverse environmental effects. The long-term goal of this project is to create a system that is viable in low tidal range locations traditionally not considered for locations of tidal energy systems, therefore increasing the overall global tidal energy portfolio. By implementing a closed system of ‘bladders’ and convergent nozzles to optimize the flow rate of the contained fluid, the proposed system can 1) derive tidal energy in low tidal range geographies 5 2) avoid typical hazards like system biofouling, marine life propeller impacts, and 3) allow for ease of installation, operation, and maintenance.
54

O que fazer com o bagaço da cana de açúcar? uma abordagem da teoria das opções reais aplicada a usinas de processamento de etanol e açúcar da região de Piracicaba

Santos, Marcio Aurélio Soares 30 November 2015 (has links)
Submitted by Marcio Aurelio Soares Santos (marrrcio@hotmail.com) on 2016-01-06T13:02:26Z No. of bitstreams: 1 Dissertação_MPAgro_Santos_MAS_Versão_Revisada_3.pdf: 1187642 bytes, checksum: 6d36e9cf2b45e719ee9c7f357535a97e (MD5) / Approved for entry into archive by Fabiana da Silva Segura (fabiana.segura@fgv.br) on 2016-01-06T14:58:11Z (GMT) No. of bitstreams: 1 Dissertação_MPAgro_Santos_MAS_Versão_Revisada_3.pdf: 1187642 bytes, checksum: 6d36e9cf2b45e719ee9c7f357535a97e (MD5) / Made available in DSpace on 2016-01-06T15:04:43Z (GMT). No. of bitstreams: 1 Dissertação_MPAgro_Santos_MAS_Versão_Revisada_3.pdf: 1187642 bytes, checksum: 6d36e9cf2b45e719ee9c7f357535a97e (MD5) Previous issue date: 2015-11-30 / O uso de resíduos da indústria canavieira, em particular o bagaço, é tema que ganha relevância desde a retomada do mercado de biocombustíveis, quando a produção ampliou significativamente o volume daquela biomassa. Existem trabalhos que tratam de apresentar subprodutos e tecnologias alternativas para o uso deste material e um conjunto outro de trabalhos apresenta análise de cenários de viabilidade econômica destas tecnologias. O objetivo deste trabalho é avaliar pela perspectiva econômico-financeira o melhor uso do bagaço da cana em um caso real. Para isto foi utilizada a Teoria das Opções Reais, como forma de analisar a melhor destinação do bagaço no horizonte de tempo de cinco anos, em uma dada a região, em um estudo de caso de uma usina sucroenergética com possibilidade de produção de etanol de segunda geração e/ou venda do bagaço in natura. Desta forma concluiu-se no caso apresentado que a produção de etanol de segunda geração em escala industrial não atrai investimentos e, sob esta ótica, deve ser postergada pois requer significativa aumento de produtividade por tonelada de matéria seca, além de substancial redução no custo das enzimas de fermentação. Ainda, foi possível também identificar a necessidade de políticas de incentivo para atração de investimentos. / The use of waste from the sugar cane industry, in particular bagasse, is a subject that becomes relevant since the resumption of the biofuels. There are works that address alternative technologies to the use of this material and a collection of other works which address the feasibilities. Therefore, this study is to evaluate the economic and financial perspective of sugarcane bagasse in an actual case. An application of the Theory of Real Options as a way to analyze the best allocation of bagasse within five years horizon, in a given region where the plant is located. The productivity and competitiveness of second-generation ethanol in contrast with the possibility of selling the bagasse. Thus it was concluded in the case presented that second-generation ethanol on an industrial scale production should be postponed since requires significant increase in productivity (litter per ton of dry bagasse) and significant reduction in the fermentation enzymes costs. Still, it was also possible to identify the need of public policy’s to develop this industry.
55

Wind power resource assessment, design of grid - connected wind farm and hybrid power system

Rehman, Shafiqur 18 May 2012 (has links)
An exponentially growing global population, power demands, pollution levels and, on the other hand, rapid advances in means of communication have made the public aware of the complex energy situation. The Kingdom of Saudi Arabia has vast open land, an abundance of fossil fuel, a small population but has always been among the front-runners where the development and utilisation of clean sources of energy are concerned. Several studies on wind, solar and geothermal sources of energy have been conducted in Saudi Arabia. Solar photovoltaic (pv) has been used for a long time in many applications such as cathodic protection, communication towers and remotely located oil field installations. Recently, a 2MW grid-connected pv power plant has been put online and much larger solar desalination plants are in planning stage. Wind resource assessment, hub height optimisation, grid-connected wind farm and hybrid power system design were conducted in this study using existing methods. Historical daily mean wind speed data measured at 8 to 12metres above ground level at national and international airports in the kingdom over a period of 37 years was used to obtain long-term annual and monthly mean wind speeds, annual mean wind speed trends, frequency distribution, Weibull parameters, wind speed maps, hub height optimisation and energy yield using an efficient modern wind turbine of 2.75MW rated power. A further detailed analysis (such as estimation of wind shear exponent, Weibull parameters at different heights, frequency distribution at different heights, energy yield and plant capacity factor and wind speed variation with height) was conducted using wind speed measurements made at 20, 30 and 40metres above ground level. As a first attempt, an empirical correlation was developed for the estimation of near-optimal hub height (HH = 142.035 * (α) + 40.33) as a function of local wind shear exponent (α) with a correlation coefficient of 97%. This correlation was developed using the energy yield from a wind turbine of 1 000kW rated power and wind speed and local exponent for seven locations in Saudi Arabia. A wind-pv-diesel hybrid power system was designed and specifications were made for a remotely located village, which is being fed 100% by diesel power generating units. The proposed system, if developed, will offset around 35% of the diesel load and therefore will result in decreased air pollution by almost the same amount. The developed wind speed maps, the frequency distributions and estimated local wind shear exponents for seven locations and energy yield will be of great help in defining the further line of action and policy-building towards wind power development and utilisation in the kingdom. The study also recommends conducting a wind measurement campaign using tall towers with wind measurements at more than one height and estimating the local wind shear exponents and developing a wind atlas for the kingdom. The study further states that a grid-connected wind farm of moderate capacity of 40MW should be developed using turbines of varying rated powers. The wind speed data was also analysed using wavelet transform and Fast Fourier Transform (FFT) to understand the fluctuation in wind speed time series for some of the stations. It is also recommended that policy-makers should take firm decision on the development of hybrid power systems for remotely located populations which are not yet connected with the grid. There are two challenges which need research: one is the effect of dust on the moving and structural elements of the wind turbines and the second is the effect of high prevailing temperatures on the performance and efficiency of the same. / Thesis (PhD)--University of Pretoria, 2012. / Mechanical and Aeronautical Engineering / PhD / Unrestricted
56

Проблемы технического перевооружения систем теплоснабжения с целью повышения их энергетической эффективности : магистерская диссертация / Problems of reconstruction of heat supply systems in order to improve their energy efficiency

Гордиенко, Н. С., Gordienko, N. S. January 2018 (has links)
В выпускной квалификационной работе описываются основные пути реконструкции систем теплоснабжения, позволяющие добиться значительного повышения их энергоэффективности, а именно переход котельной на альтернативное топливо с целью повышения энергоэффективности, снижения экономических и экологических потерь. Целью работы является поиск и формулирование основных проблем реконструкции систем теплоснабжения, развитие технологического процесса перевода котельной на альтернативное топливо, проведение энергетического и экономического обоснования предлагаемой замены. Были изучены отечественные и зарубежные публикации по проблемам реконструкции систем теплоснабжения для повышения их энергоэффективности. Приведено обоснование необходимости перевода котельной на альтернативное и экологически чистое топливо, на основе оценки основного и вспомогательного оборудования котельной, а также экологического благополучия территории, прилегающей к котельной. Разработан технологический процесс перевода котельной на альтернативное и экологически безопасное топливо, выявлена и доказана необходимость модернизации оборудования для использования альтернативного топлива. Были определены существующие методы модернизации котла, работающего на угле для альтернативного и экологически чистого топлива. Выполнено экономическое обоснование предлагаемой замены. / This final qualifying work describes the main ways of reconstruction of heat supply systems, allowing achieving a significant increase in the energy efficiency of these systems, namely the transfer of the boiler to alternative fuel in order to improve energy efficiency, reduce economic and environmental losses. The purpose of the work is to consider and formulate the main problems of reconstruction of heat supply systems, development of the technological process of transferring the boiler house to alternative fuel, implementation of energy and economic justification of the proposed replacement. Domestic and foreign publications on the problems of reconstruction of heat supply systems in order to improve their energy efficiency were studied. The substantiation and relevance of the transfer of the boiler house to alternative and environmentally friendly fuel was discussed, for which the assessment of the main and auxiliary equipment of the boiler house, as well as the ecological well-being of the territory adjacent to the boiler house. The technological process of transfer of a boiler room to alternative and environmentally friendly fuel was developed, need of modernization of the equipment for use of pellet fuel is revealed and proved. The existing methods of modernization of the boiler unit operating on coal for alternative and environmentally friendly fuel were identified. Economic justification of the proposed replacement was done.
57

Economic Resilience, Disasters, and Green Jobs: An Institutional Collective Action Framework

Ismayilov, Orkhan M. 12 1900 (has links)
This dissertation is about economic resilience of local governments to natural disasters. Specifically, the dissertation investigates resilience on regional level. Moreover, the dissertation also investigates growth in the green job sector in local governments. The findings indicate that local governments working with each other helps green job creation. In addition, the dissertation finds that green jobs, following disasters, experience three percent growth. This dissertation is important because it investigates the relationship between climate- related disasters and green jobs, which is an area that is under-investigated.
58

Understanding Coulombic Efficiency Limitations in an Acid-Base Energy Storage System: Mass Transport Through Nafion

Pickering, Jason C., Pickering 31 August 2018 (has links)
No description available.
59

Clean technology transition potential in South Africa's gold mining sector : case of Harmony's Kusasalethu Mine

Chavalala, Bongani 03 July 2014 (has links)
Countries and governments around the world have accepted the scientific argument on the prevalence and the possible effect of global warming and climate change on the environment, world economy and ultimately human life (Nhamo, 2011). Amongst all industrial corporations, the mining industry is the biggest environmental polluter due to its extractive nature and energy intensive operations. However because of its economic importance, it cannot be abandoned, instead it needs to find a win-win situation, where it continues to succeed but minimizes environmental damage. This thesis aims to examine the possible impact of clean technology on the sustainability of South African gold mining sector. Specifically, the study aims to determine the drivers behind the move towards clean technologies and methods, identify challenges and opportunities associated with this transition at Harmony Gold’s Kusasalethu mine. This was achieved through using Kusasalethu as a case study to which investigations of the effectiveness of clean technology and methods were carried out. The case study was multidimensional; exploring the effect of clean technology on energy consumption, greenhouse gas emission (GHG), water consumption, cyanide management and Kusasalethu’s financial performance. While the case study was largely qualitative it involved quantitative data analysis that had to be triangulated with other data sources and data gathering instruments to achieve legitimacy. This meant that the study had to adopt the mixed research methods. The instruments used included; key informant interviews, and document analysis, structured questionnaire and a set of open ended questions that served as interview guide. The qualitative data were analyzed by means of coding, descriptions, typologies, taxonomies and visual representations, whilst quantitative data were processed through Microsoft Excel to generate various forms of descriptive statistics. The findings indicate that resource consumption (energy, water, cyanide) depends on the mine design and gold output rate. Clean technology implementation at Kusasalethu helped the mine reduce energy consumption and GHG emissions. However scope 2 (indirect GHG emissions associated with energy consumption) is also determined by coal production technologies and methods used by coal mines. Although data on Kusasalethu water and cyanide management and related technologies was not available, the aggregate data for all Harmony Gold mines indicated higher annual water and cyanide consumption during 2010 and 2012. In terms of Kusasalethu’s financial performance and clean technology adaptation, acquisition of clean technologies increased capital expenditure temporarily. However, the positive effects of the clean technology transition and implementation minimized operational cost and increased operational profit greatly. Although adopting clean technologies calls for increased capital expenditure, this study reveals that this expenditure pays off in lower operation costs for the mine and the environment benefits through lower GHG emission. However, clean technologies are yet to impact significantly in lowering water and cyanide consumption levels as they do with energy consumption. The study concluded that clean technology and methods played a positive role on Kusasalethu’s environmental impact and financial performance by reducing energy consumption and GHG emissions. Though, more need to be done in terms of water and cyanide management. / Environmental Sciences / M. Sc. (Environmental Management)
60

Clean technology transition potential in South Africa's gold mining sector : case of Harmony's Kusasalethu Mine

Chavalala, Bongani 03 July 2014 (has links)
Countries and governments around the world have accepted the scientific argument on the prevalence and the possible effect of global warming and climate change on the environment, world economy and ultimately human life (Nhamo, 2011). Amongst all industrial corporations, the mining industry is the biggest environmental polluter due to its extractive nature and energy intensive operations. However because of its economic importance, it cannot be abandoned, instead it needs to find a win-win situation, where it continues to succeed but minimizes environmental damage. This thesis aims to examine the possible impact of clean technology on the sustainability of South African gold mining sector. Specifically, the study aims to determine the drivers behind the move towards clean technologies and methods, identify challenges and opportunities associated with this transition at Harmony Gold’s Kusasalethu mine. This was achieved through using Kusasalethu as a case study to which investigations of the effectiveness of clean technology and methods were carried out. The case study was multidimensional; exploring the effect of clean technology on energy consumption, greenhouse gas emission (GHG), water consumption, cyanide management and Kusasalethu’s financial performance. While the case study was largely qualitative it involved quantitative data analysis that had to be triangulated with other data sources and data gathering instruments to achieve legitimacy. This meant that the study had to adopt the mixed research methods. The instruments used included; key informant interviews, and document analysis, structured questionnaire and a set of open ended questions that served as interview guide. The qualitative data were analyzed by means of coding, descriptions, typologies, taxonomies and visual representations, whilst quantitative data were processed through Microsoft Excel to generate various forms of descriptive statistics. The findings indicate that resource consumption (energy, water, cyanide) depends on the mine design and gold output rate. Clean technology implementation at Kusasalethu helped the mine reduce energy consumption and GHG emissions. However scope 2 (indirect GHG emissions associated with energy consumption) is also determined by coal production technologies and methods used by coal mines. Although data on Kusasalethu water and cyanide management and related technologies was not available, the aggregate data for all Harmony Gold mines indicated higher annual water and cyanide consumption during 2010 and 2012. In terms of Kusasalethu’s financial performance and clean technology adaptation, acquisition of clean technologies increased capital expenditure temporarily. However, the positive effects of the clean technology transition and implementation minimized operational cost and increased operational profit greatly. Although adopting clean technologies calls for increased capital expenditure, this study reveals that this expenditure pays off in lower operation costs for the mine and the environment benefits through lower GHG emission. However, clean technologies are yet to impact significantly in lowering water and cyanide consumption levels as they do with energy consumption. The study concluded that clean technology and methods played a positive role on Kusasalethu’s environmental impact and financial performance by reducing energy consumption and GHG emissions. Though, more need to be done in terms of water and cyanide management. / Environmental Sciences / M. Sc. (Environmental Management)

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