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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.
11

Techno-economic analysis of an off-grid micro-hydrokinetic river system as a remote rural electrification option

Koko, Sandile Phillip January 2014 (has links)
Thesis (M. Tech. (Electrical Engineering )) - Central University of Technology, Free State, 2014 / Remote rural electrification via grid-extension is a challenging solution due to high connection costs and low electricity consumption rate. As a result, it is difficult to recover the initial investment costs. Therefore, electrification is made possible by means of the commonly used off-grid approaches such as solar, wind, diesel generator and conventional micro-hydro. However, owing to non-continuous availability of sunlight and wind, high cost of diesel fuel, and requirements for construction of diversion weirs, these off-grid approaches might not offer a cost-effective and reliable solution to low income rural residents. There are many rural communities throughout the world without access to grid electricity and with access to flowing water. An off-grid micro-hydrokinetic river (MHR) system is one of the promising technologies to be used in remote rural areas with flowing water. It can bring sustainable improvement to their quality of life due to its high energy density and minimal environmental impact. This technology is still in the development stage and there is a lack of application, especially in rural areas. Hence, this study investigates the current status of MHR technology in rural applications. To demonstrate the economic feasibility of an off-grid MHR system, a rural site with multiple energy sources within South Africa has been used. The economic benefit offered by this proposed system at the selected site is compared to the economic benefits offered by other commonly used standalone systems such a solar, wind and diesel generator (DG). This economic comparison has been performed by making use of a Hybrid Optimization Model for Electric Renewable (HOMER) simulation tool. Grid extension has also been used as a comparison method for obtaining an economical distance between grid lines and the remote rural site. The results highlighted the acceptable economic performance of the MHR system. Finally, most of the available modelling and simulation tools for mechanical and electrical systems are not equipped with hydrokinetic modules. Hence, an MHR system model has been developed in MATLAB/Simulink in order to study its dynamic performance as submitted to variable water resource. Its performance has then been compared to the performance of a wind system counterpart for generating the same amount of electrical power. This proved/verified that the proposed system can generate electricity markedly cheaper than a wind system even in areas with adequate wind resource within South Africa.
12

Techno-economic analysis of an off-grid micro-hydrokinetic river system as a remote rural electrification option

Koko, Sandile Phillip January 2014 (has links)
Thesis (M. Tech. (Electrical Engineering )) - Central University of Technology, Free State, 2014 / Remote rural electrification via grid-extension is a challenging solution due to high connection costs and low electricity consumption rate. As a result, it is difficult to recover the initial investment costs. Therefore, electrification is made possible by means of the commonly used off-grid approaches such as solar, wind, diesel generator and conventional micro-hydro. However, owing to non-continuous availability of sunlight and wind, high cost of diesel fuel, and requirements for construction of diversion weirs, these off-grid approaches might not offer a cost-effective and reliable solution to low income rural residents. There are many rural communities throughout the world without access to grid electricity and with access to flowing water. An off-grid micro-hydrokinetic river (MHR) system is one of the promising technologies to be used in remote rural areas with flowing water. It can bring sustainable improvement to their quality of life due to its high energy density and minimal environmental impact. This technology is still in the development stage and there is a lack of application, especially in rural areas. Hence, this study investigates the current status of MHR technology in rural applications. To demonstrate the economic feasibility of an off-grid MHR system, a rural site with multiple energy sources within South Africa has been used. The economic benefit offered by this proposed system at the selected site is compared to the economic benefits offered by other commonly used standalone systems such a solar, wind and diesel generator (DG). This economic comparison has been performed by making use of a Hybrid Optimization Model for Electric Renewable (HOMER) simulation tool. Grid extension has also been used as a comparison method for obtaining an economical distance between grid lines and the remote rural site. The results highlighted the acceptable economic performance of the MHR system. v Finally, most of the available modelling and simulation tools for mechanical and electrical systems are not equipped with hydrokinetic modules. Hence, an MHR system model has been developed in MATLAB/Simulink in order to study its dynamic performance as submitted to variable water resource. Its performance has then been compared to the performance of a wind system counterpart for generating the same amount of electrical power. This proved/verified that the proposed system can generate electricity markedly cheaper than a wind system even in areas with adequate wind resource within South Africa.
13

Forecasting hourly electricity demand in South Africa using machine learning models

Thanyani, Maduvhahafani 12 August 2020 (has links)
MSc (Statistics) / Department of Statistics / Short-term load forecasting in South Africa using machine learning and statistical models is discussed in this study. The research is focused on carrying out a comparative analysis in forecasting hourly electricity demand. This study was carried out using South Africa’s aggregated hourly load data from Eskom. The comparison is carried out in this study using support vector regression (SVR), stochastic gradient boosting (SGB), artificial neural networks (NN) with generalized additive model (GAM) as a benchmark model in forecasting hourly electricity demand. In both modelling frameworks, variable selection is done using least absolute shrinkage and selection operator (Lasso). The SGB model yielded the least root mean square error (RMSE), mean absolute error (MAE) and mean absolute percentage error (MAPE) on testing data. SGB model also yielded the least RMSE, MAE and MAPE on training data. Forecast combination of the models’ forecasts is done using convex combination and quantile regres- sion averaging (QRA). The QRA was found to be the best forecast combination model ibased on the RMSE, MAE and MAPE. / NRF
14

Rural energy systems and the rural development process: a case study from Limpopo Province

Ntobeng, Ntwampe Albert 30 April 2007 (has links)
The rapid and sustained development of the rural regions of South Africa continues to pose an extraordinary challenge to the development community of the country. Policy makers continue to be overwhelmed by the lack of development in the rural areas in spite of the various efforts made to develop them. A review of the publications and development plans of the study region indicates that the planners have for long been pre-occupied with taking limited perspectives of the development planning problems. Development plans have been conceived and implemented in terms of individual sectors instead of looking at their relations with other sectors and regions. This study seeks to make a contribution to the solution of the development problems of the rural areas of the former homeland regions by demonstrating how an integrated approach to the research process and to development planning could make a difference to the lives of the rural communities. This theme is illustrated with reference to the rural energy sector and its relations with the broader regional development problems, challenges and plans of the Sekhukhune district municipality of the Limpopo Province. / GEOGRAPHY / MA (GEOGRAPHY)
15

Rural energy systems and the rural development process: a case study from Limpopo Province

Ntobeng, Ntwampe Albert 30 April 2007 (has links)
The rapid and sustained development of the rural regions of South Africa continues to pose an extraordinary challenge to the development community of the country. Policy makers continue to be overwhelmed by the lack of development in the rural areas in spite of the various efforts made to develop them. A review of the publications and development plans of the study region indicates that the planners have for long been pre-occupied with taking limited perspectives of the development planning problems. Development plans have been conceived and implemented in terms of individual sectors instead of looking at their relations with other sectors and regions. This study seeks to make a contribution to the solution of the development problems of the rural areas of the former homeland regions by demonstrating how an integrated approach to the research process and to development planning could make a difference to the lives of the rural communities. This theme is illustrated with reference to the rural energy sector and its relations with the broader regional development problems, challenges and plans of the Sekhukhune district municipality of the Limpopo Province. / GEOGRAPHY / MA (GEOGRAPHY)
16

An evaluation of the quality customer service delivered by Eskom to rural household customers in the Eastern Cape

Myoli, Mncedi Eric January 2011 (has links)
[Abstract - Conclusion]: This research study confirms the theory in the literature review on delivery of quality service to customers and premise that there is a statistically significant difference between Eskom service as perceived by rural prepaid household customers and their expectations. This study also highlights the need for Eskom management to take into cognisance the unique rural prepaid customer service needs and how to meet them, perhaps a differentiated service approach rather than a one-strategy-fits-all approach. This is in view of gaps created between expectations and perceptions of service, especially in the reliability dimension that could require a concentrated or changed performance approach to close them.
17

An assessment of household energy use, emissions and deforestation in the Thulamela Local Municipality

Ahunamure, Solomon Eghosa 02 February 2016 (has links)
MENVM / Department of Geography and Geo-Information Sciences / Fuel wood is regarded as a major source of energy around the world, particularly in developing nations. Most rural communities around the world, consider forests as the repository of stored energy. The high dependence on forests as a source of fuel wood has a major impact on vegetation because trees take a long time to regenerate to maturity, hence high dependence leads to deforestation. Fuel wood is used for household needs, such as cooking and heating and its uses contribute to the emissions of Green House Gases (GHG) such as CO2, CH4, and Black Carbon amongst others. The study assesses household energy use, the amount of carbon dioxide emitted from the combustion of fuel wood, the extent of de-vegetation and strategies to ensure sustainable energy provisions in the case study areas. Primary and secondary methods were used to collect data. The data were analysed using Statistical Package for the Social Sciences (SPSS 21.0), showing the frequency distribution, measures of central tendency and chi-square to determine the extent of fuel wood used in relation to electricity. The primary data were collected through personal observations, field surveys, interviews and questionnaires, while secondary data included the 2011 South Africa Census data and remote sensing images, which with the aid of GIS, were used in mapping the vegetation change.
18

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

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