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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.
31

Investigation into the characteristics and possible applications of biomass gasification by-products from a downdraft gasifier system

Melapi, Aviwe January 2015 (has links)
Biomass gasification has attracted the interest of researchers because it produces zero carbon to the atmosphere. This technology does not only produce syngas but also the byproducts which can be used for various application depending on quality.The study conducted at Melani village in Alice in the Eastern Cape of South Africa was aimed at investigating the possible applications of the gasification byproducts instead of being thrown away. Pine wood was employed as the parent feedstock material for the gasifier. Biomass gasification by-products were then collected for further analysis. The studied by-products included tar(condensate), char, soot and resin. These materials were also blended to produce strong materials.The essence of the blending was to generate ideal material that is strong but light at the same time.The elemental analysis of the samples performed by CHNS analyser revealed that carbon element is in large quantities in all samples. The FTIR spectra showed almost similar results for all the studied samples, since the samples are end products of lignocellulosegasification. SEM gave the sticky images of resin as well as porous char structures. Char showed a higher heating value of 35.37MJ/Kg when compared to other by-products samples.
32

Sustainable energy solutions for the residences of Stellenbosch University

Smit, Georgina 03 1900 (has links)
Thesis (MPhil (Sustainable Development Planning and Management))--University of Stellenbosch, 2009. / The research objective of this assignment is to investigate technological options for sustainable energy solutions in the residences of Stellenbosch University. Conventional energy systems are contributing towards the degradation of global environmental sustainability. An alternative energy future exists if sustainable energy solutions, via renewable energy or energy efficiency, are adopted but these solutions await the political will and institutional governance to be implemented. A niche group of universities are modelling themselves around the sustainable energy agenda. As institutional spaces of learning, research and breeding grounds for new ways of thinking, universities stand poised to engage future leaders with local solutions to global energy dilemmas. It is argued that sustainable energy is necessary, it is possible and other universities are implementing it in various formats. The author of this thesis, a student at Stellenbosch University, was prompted to ask: what opportunities exist for Stellenbosch University to implement sustainable energy? The research objective focused on end use energy efficiency as means, out of all the technical options theoretically possible today, to implement sustainable energy solutions in the residences of Stellenbosch University. The focus of end use efficiency was specific to water heating, lighting and appliance use, for which technical solutions exist. This exploratory research was conducted via a macro, secondary data analysis of the quantitative data which detailed the energy consumption of residences in kilowatt hours as well as a micro, case study to facilitate a qualitative and quantitative analysis of the behavioural and leadership dynamics involved with technological implementation. The findings revealed that end use energy efficiency is a possible means for sustainable energy use within the residences of Stellenbosch University. However, the use of heat pump water heating technology in the majority of the residences and the omission of air conditioning in the residences results that the greatest potential for energy efficiency measures are not available. The centralised kitchen infrastructure requires highly rated equipment to deal with the swift throughput of meal times during the residences. The remaining focus areas of energy consumption, residential living, therefore, poses the greatest opportunity for end use energy efficiency. This posits residential lighting and appliance use as the focal point of the investigation. The findings concluded recommended courses of action for the University, residential leaders and students. The holistic and integrated approach to the research objective, guided by systems thinking and ecological design, capacitates actors at three different levels to pro actively implement end use energy efficiency. A by product of the micro, case study was a tool which the new Green House Committee members can now use to identify key points of energy efficiency and energy conservation in their residences. The local solutions generated by this thesis significantly contributed towards taking the first step towards mitigating global, national and community problems. Sustainable energy solutions are necessary, available and being implemented in other universities. End use energy efficiency, as a means to sustainable energy, is necessary, available and possible to implement within the residences of Stellenbosch University. / Centre for Renewable and Sustainable Energy Studies
33

The attitude, awareness and willingness to pay for solar water heaters in the Cape Town region

Ravens, Bradley 12 1900 (has links)
Thesis (MDF (Development Finance))--Stellenbosch University, 2008. / ENGLISH ABSTRACT: This study focuses on the level of acceptance, awareness, and willingness to pay for a solar water heater in Cape Town. When referring to 'acceptance' the study is referring to a respondent's preparedness to adopt the use of a solar water heater and to have one installed at his/her home. When referring to the respondent's 'awareness', reference is made to the degree of knowledge a respondent possesses about the use and basic functioning of solar water heaters. The 'willingness to pay' is an indication of a respondent's preparedness to pay for a solar water heater and how much he/she is prepared to pay. This research was initiated because it was felt that more households in the middle and upper-income sector should be making use of solar water heaters in Cape Town in an effort to reduce their electricity consumption. Furthermore, it is in this income sector that we find the greatest consumption of electricity for the sale purpose of heating water. A questionnaire was compiled to gauge the knowledge, opinion and acceptance of solar water heaters in Cape Town. These questionnaires were distributed in various suburbs within Cape Town, and focused on middle-income to upper-income groups. The middle and upper-income households would install solar water heaters if they received an incentive such as state subsidies. These households also need further education in relation to solar water heaters because their knowledge in this regard seems limited. Aesthetics and costs also seem to influence whether the middle and upper-income group would install solar water heaters, and income may also play a role in group affiliation. / AFRIKAANSE OPSOMMING: Hierdie navorsing fokus op die aanvaarding, bewustheid en bereidheid om vir sonkrag waterverhitters te betaal in Kaapstad. Die verwysing na 'aanvaarding' dui op die respondent se gewilligheid om die sonkrag-waterverhitter te gebruik en om een in sy/haar huis te installeer. Die verwysing na die respondente se 'bewustheid', dui op hulle kennis oor die basiese werking van 'n sonkrag-waterverhitter. Die 'bereidheid' om te betaal is 'n aanduiding van die respondent se bereidheid om te betaal vir 'n sonkrag-waterverhitter en hoeveel hy/sy bereid is om daarvoor te betaal. Hierdie navorsing is onderneem omdat die gevoel bestaan dat nie baie huise in die middel- en hoe-inkomste huishoudings gebruik maak van 'n sonkrag-waterverhitter om hul elektrisiteitsverbruik te verminder nie. Die huishoudings in hierdie inkomstesegment is die grootste verbruikers van elektrisiteit slegs vir die verhitting van water. 'n Vraelys is opgestel om die kennis, opinie, en aanvaarding van sonkrag-waterverhitters in Kaapstad te bepaal. Die vraelyste is in verskeie woongebiede in Kaapstad versprei, met 'n fokus op die middel- en hoë-inkomste huishoudings. Die huishoudings in die middel- en hoë-inkomstesegment sal sonkrag-waterverhitters installeer as hulle 'n aansporing kry soos 'n staatsubsidie. Die respondente van die middel en hoë-inkomste huishoudings het verdere opvoeding nodig rakende sonkragwaterverhitters, want hul kennis in die verband is min. Dit blyk of estetiese en koste-oorwegings die middel- en hoë-inkomste huishoudings beinvloed met betrekking tot die installasie van sonkrag-waterverhitters, en inkomste mag ook 'n rol speel ten opsigte van groepaffiliasie.
34

The economic feasibility of non-farm biodiesel production in KwaZulu-Natal, South Africa.

Sparks, Garreth David. January 2010 (has links)
Recent years have seen an unprecedented global increase in the production and use of biofuels. This has been driven primarily by government support for biofuel industries. Soybeans are the only field crop produced in sufficient quantities in the province of KwaZulu- Natal (KZN) that the South African (SA) industrial biofuel strategy identifies as a potential biodiesel feedstock. Thus, this study is an evaluation of the economic feasibility of producing biodiesel on farms from soybeans in the main soybean-producing regions of KZN, using batch processing biodiesel plants. A mixed integer linear programming model was developed to simulate observed agricultural land rental rates (estimated at 4.48% of the market value of land) and cropping behaviour of commercial crop farms in the study regions. The model incorporates various alternative crops, crop rotations, tillage techniques, arable land categories and variance-covariance matrices to account for risk in production. All data are on a real 2009/10 basis. The model is used to predict possible farmer investment behaviour and determine the minimum biodiesel subsidy required to stimulate soybean-based biodiesel production in the study areas. Results suggest that biodiesel production is currently not an economically viable alternative to fossil fuel, and that the incentives and commitments outlined by the current industrial biofuel strategy are inadequate to both establish and sustain a domestic biodiesel industry. Under baseline assumptions, a realistic minimum implicit subsidy of R4.37 per litre of biodiesel is required to draw soybean-based biodiesel production into the optimum solution for commercial farms. The economic feasibility of on-farm biodiesel production is highly dependent on the soybean price (i.e., the feedstock input cost) and the soybean oilcake price (i.e., the highest valued byproduct). Thus, future promotion of biodiesel ventures could primarily target a reduction of feedstock costs through the development of new technologies which increase yields of available feedstocks and/or permit the use of lower cost alternatives. Higher subsidy levels are anticipated for: (i) small-scale initiatives (particularly in the absence of a rental market for cropland); (ii) soybean-based biodiesel production in areas with less suitable growing conditions for cultivating soybeans; and (iii) using sunflower and/or canola as biodiesel feedstock. To the author’s knowledge no other previous studies have attempted to quantify the minimum level of support needed to stimulate biodiesel production in South Africa. The SA industrial biofuels strategy promotes a development-oriented strategy with feedstock produced by smallholders and processed by traditional producer-owned cooperatives. However, traditional cooperatives suffer from a myriad of institutional problems that are associated with ill-defined property rights. As such, it is argued that these initiatives will fail to attract the capital and expertise needed to process biodiesel. This research, therefore, highlights the need for South Africa’s current Cooperatives Act to be amended. Accordingly, this also infers a need to revise the proposed SA industrial biofuels strategy. It is concluded that smallholder participation in biodiesel ventures would require a rental market for cropland, co-ownership of the processing plant in a non-traditional cooperative or investor-owned firm, information and training, and a high level of government subsidy. This research advocates that government consider promoting soybean oil extrusion ventures as a means of stimulating rural development for small-scale farming initiatives rather than soybean-based biodiesel production, as they will likely require less government assistance, whilst potentially combating the food versus fuel debate against biofuels. This is compounded by the fact that South Africa has historically been a net importer of both soybean oilcake and soybean oil. Importantly, however, the proliferation of such initiatives should not be based on the current notion of traditional cooperatives. The need for government to play a proactive role in such ventures through facilitating the development of appropriate business models which stimulate private investment in feedstock and processing facilities is clearly evident. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
35

Climate change mitigation strategies in relation to the forestry and energy sectors in SACD region with emphasis in DRC and RSA as case studies

Mumbere, Mbasa Ndemo 06 1900 (has links)
The main objective of this study is to evaluate climate change mitigation strategies in the forestry and energy sectors in the SADC with emphasis on the DRC and the RSA. This study is evaluative and cross-sectional. Its results were got through interviews of 56 key informants using the interview guide, and four focus group discussions in the DRC based on the focus group guide. The non-probability sample, mainly the purposive sample and the snowballing sampling were used. After the data analysis, the following results were found: In terms of the strategies for fighting drivers of deforestation both in the DRC and in RSA, it was revealed that the DRC focuses more on the REDD+ projects and NGO activities while the RSA protects its small existing natural forests through Acts, laws, advanced research and establishment of commercial plantations. The results which are related to the contribution of REDD programmes and NGOs to climate change mitigation in the RSA and the DRC have revealed that there are no REDD programmes in the RSA for carbon stock. In the DRC, the NOVACEL REDD+ pilot project has a carbon stock of 60 000 tons which continues to grow with 8 tons of CO2 /ha/year; 210 tons/ha/year on the left side of the Congo River, and on the right side 195 tons/ha/year is generated by the Isangi Geographically Integrated REDD+ pilot project. The WCS Mambasa Forestry REDD+ pilot project has 230 tons/ha/year, while 16 000 tons of CO2/year are stocked under the Luki REDD+ pilot project. The Eco-Makala and Equatorial REDD+ pilot projects have not yet estimated their carbon stocks. Regarding the involvement of the civil society in activities of climate change mitigation in the DRC, people are more involved in REDD’s alternative activities which are funded by the projects. However, in the RSA, people are used as labour in commercial plantations. The RSA derives its major energy from coal (94%) but the DRC has a high potential in hydropower that can generate up to 100 000 MGW. On the use of remote sensing, both the DRC and the RSA employ remote sensing but the RSA has a Spatial Agency while the DRC does not / College of Agriculture and Environmental Sciences / D. Litt. et Phil. (Environmental Science)
36

The perceived visual impacts and attitudes of the Grahamstown community towards the Waainek Wind-Farm

Cruickshank, Kyle Mark January 2014 (has links)
Renewable energy has become an important feature of most modern economies with clean and non-exhaustible sources of power being given a greater significance. Wind energy is one of the favoured renewable, as it is (2013) generally the cheapest and most mature technology available for commercial use. The South African government, as outlined by the Department of Energy's Integrated Resource Plan (IRP), aims to install 5 GW (Gigawatts) of wind energy by 2020. However, South Africa has had little experience in the wind energy industry which is limited to two projects, Klipheuwel (2002) and Darling (2008). Much effort has been dedicated to calculating balance sheet costs, which carries uncertainty due to the high reliance on country specific and site specific variables. An aspect which deserves more attention, and is often ignored, is the public‟s attitudes towards local wind farm developments, which have been known to "make or break" a project during the planning stages. Public backlashes have mostly been concerned with the visual "intrusiveness" of wind farms in the landscape. Detrimental effects on scenery, while seemingly innocuous, are acknowledged as being the single largest barrier to successful wind farm development. Individuals within an area become sentimentally attached to their surroundings, where significant rapid changes in the landscape are viewed as "damage". Economics recognises such declines in scenic resources as market failures, where an externalised cost is passed on to the public and is often not accounted for by private parties responsible for the liability. The primary objective therefore was to measure the magnitude of the visual impact, caused by the Waainek Wind Farm, on the Grahamstown community. Conventional NIMBY¹ (not in my back yard) reasoning, which seeks to explain local wind farm resistance, has attracted criticism with regard to its simplistic approach to wind farm problem identification. Contemporary arguments propose that NIMBY is a poor explanation for the trouble experienced on the local level because it groups problems into one all-encompassing term, leaving much of the discontent unexplained. Instead, the NIMBY explanation is really a broad set of unattended problems, largely resulting from the unsound practices present in the public participation process. Insufficient community involvement and disparities in the negotiation power structures have become the recent focus in wind farm literature. Essentially, these disparities force opposition groups to select factors which may seem more serious to developers, leading to ineffective remedial measures because the core underlying problems are not being remedied. Thus these considerations formed an additional area of investigation. No NIMBY effect was found for the Grahamstown community, as support for both the local and general level was roughly 80%. The public participation process on the other hand revealed that while many found the practices of the developer to be unfair, attitudes towards the wind farm were not adversely affected, especially for the lower income Grahamstown East areas. While the public participation process in this instance did not have any effect on people’s attitudes, careful inspection of the circumstances need to be given. Wind farms are new to South Africa, where the novelty and benefits are the focus of enthusiasm. Job opportunities as well as clean energy are positive drivers for attitudes; however given time, once the anticipation for wind farms dulls, real problems may be revealed. Thus it is crucial to implement good practice procedures during the public participation process, especially when national adoption rates of wind energy are low. Early implementation of an effective public participation process system will ensure that when major problems do arise in future projects, experience and institutional processes would have had ample opportunity to evolve appropriately over a period of time. The double bounded Contingent Valuation Method was used to value the impact of the wind farm on the Waainek scenery through a hypothetical scenario based procedure which presented pictures of the landscape before and after the wind farm had been installed. Based on the perceived impact of the wind farm, respondents were asked their Willingness to Pay to relocate the development, based solely on visual impacts. Learning design Contingent Valuation (Bateman et al., 2008) is a novel technique employed to familiarize respondents with the hypothetical market institution as well as the scenic goods being valued. Average Willingness to Pay was found to be R67 per month, with a final total monthly negative visual impact of R104,000 to R121,000 per month for the entire Grahamstown community. Grahamstown Central (middle-high income) residents were more likely to pay than Grahamstown East (low-middle income) East residents because of socio-economic differences present in each area. A ranking exercise determined that while negative visual impacts are present, the overall benefits derived from the wind farm are potentially much higher. Additionally, positive scenic improvements were found, but were not measured due to time constraints, and would have worked to reduce the net visual impact of the Waainek Wind Farm. ¹Problem where individuals support the general concept of wind power, but when it comes to local implementation, opposition to the development arises within the same group.

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