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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 use and agricultural productivity a comparison of Amish and modern agricultural systems /

Craumer, Peter R. January 1977 (has links)
Thesis--Wisconsin. / Includes bibliographical references (leaves 152-163).
2

Power alcohol from agricultural and agro-industrial products an appropriate measure to develop energy sources for agricultural developing country /

Jiraphol Sintunawa. January 1978 (has links) (PDF)
Thesis (M.Sc. (Technology of Environmental Management)) -- Mahidol University, 1978.
3

Sustainable agriculture, renewable energy and rural development an analysis of bio-energy systems used by small farms in China /

Zhou, Aiming. January 2006 (has links)
Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: John Byrne, School of Urban Affairs & Public Policy. Includes bibliographical references.
4

Searching for the biofuel energy crisis in rural Java

McGranahan, Gordon. January 1986 (has links)
Thesis (Ph. D.)--University of Wisconsin-Madison, 1986. / Cover title. Includes bibliographical references (p. 362-387).
5

Agriculture, energy and sustainability : case studies of a local farming community in Sweden /

Jansén, Jan. January 2000 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2000. / Includes bibliographical references.
6

Potential effects of wind electric generators on conventional electric generators in Kansas

Duffey, Christopher Kear. January 1984 (has links)
Call number: LD2668 .T4 1984 D83 / Master of Science
7

Private sector innovation in biofuels in the United States induced by prices or policies.

Deshmukh, Rupa. January 2008 (has links)
Thesis (M.S.)--Rutgers University, 2008. / "Graduate Program in Food and Business Economics." Includes bibliographical references (p. 42-44).
8

Análise energética e econômica da produção de leitões na região oeste do Paraná

Paula, Germano de [UNESP] 10 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-10Bitstream added on 2014-06-13T20:42:02Z : No. of bitstreams: 1 paula_g_dr_botfca.pdf: 659666 bytes, checksum: 21b684224c1b80ad69f55f0ef526ce66 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O estágio de desenvolvimento atual da agricultura permitiu que se alcançassem altos índices de produtividade das lavouras, criações e produção de insumos, e complexos agroindustriais mais eficientes, disponibilizando bens e serviços em grande escala ao consumidor final. Neste contexto e frente ao futuro incerto e de escassez das fontes não renováveis de energia, principalmente as derivadas de combustíveis fósseis não renováveis, coloca-se como tarefa aos agentes dos complexos agroindustriais desenvolver fontes de energia renováveis alternativas. Nesse contexto, o Brasil destaca-se na produção de plantas e animais como principais fontes de energias renováveis e tornou-se um dos precursores nas pesquisas que conseguiram gerar novas fontes de energias. Nesse contexto, a suinocultura também tem contribuído na produção de fontes de energia renovável, com a transformação de dejetos de suínos em fertilizantes e biogás. Sendo assim, os agentes produtivos da suinocultura buscam opções para amenizar os impactos ambientais da atividade e torná-la mais sustentável ambientalmente. O presente trabalho teve por objetivo analisar indicadores de eficiências energética e econômica da produção de leitões, na fase de creche, da região Oeste do Paraná. Mais especificamente, procurou-se determinar possíveis diferenças na eficiência energética e econômica de produtores que fabricaram rações nas suas propriedades e produtores que compraram rações da Cooperativa. O processo de determinação da amostra dos suinocultores foi por acessibilidade e não probabilística. Para simulações diferenças de eficiência econômica entre os grupos de produtores cooperados, utilizou-se o programa Minitabi, do Software estatística e dados digitados em planilhas do aplicativo Microsoft versão 2007. Os sistemas de produção... / The current stage of development of agriculture made it possible to reach high productivity of crops, livestock and production inputs, agro-industrial complex and more efficient, providing goods and services on a large scale to the final consumer. In this context, and facing the uncertain future and lack of non-renewable sources of energy, especially those derived from non-renewable fossil fuels, there is the task of the agents of the agroindustrial complex to develop renewable energy alternatives. In this context, Brazil stands out in the production of plants and animals as main sources of renewable energy and became one of the pioneers in research that could generate new sources of energy. In this context, the pork industry has also contributed in the production of renewable energy sources, with the processing of pig manure into fertilizer and biogas. Therefore, the swine production agents seek options to mitigate the environmental impacts of the activity and make it more environmentally sustainable. This study aimed to analyze indicators of energy and economic efficiencies of production of piglets in nursery phase, the western Paraná. More specifically, we sought to determine possible differences in energy efficiency and cost-effective producers who feed manufactured in their properties and feed producers who bought the Cooperative. The process of determining the sample of pig farmers was due to accessibility and nonprobabilistic. For simulations of economic efficiency differences between the groups of cooperative producers... (Complete abstract click electronic access below)
9

Techno-economic evaluation of using maize for bioethanol production compared to exporting it from South Africa

Ndokwana, Ayanda Lawrence January 2016 (has links)
Thesis ( MTech (Business Administration))--Cape Peninsula University of Technology, 2016. / Capital investment in bioethanol production requires sound economic feasibility studies. This study investigated the economic feasibility of using maize as a feedstock to produce bioethanol in South Africa. There is a huge opportunity to use dedicated underutilised arable land to grow maize which can be used for both consumption and bioethanol production. The study used 200 000 ton/year of maize that could have been exported to SADC countries to size a plant that produces 80 million litres per year of bioethanol. An advanced bioethanol processing technology that separates the fibre/bran which is burnt in a steam boiler to produce process steam was selected owing to advantages such as low energy consumption and capital expenditure on fermentation and distillation equipment. This study employed a combination of qualitative and quantitative methods to gather data. The findings from a qualitative instrument indicated that a majority of respondents were in favour of the decision of excluding maize made by the South African government. Putting security of food at risk and uncertainty in the profitability of a maize-fed bioethanol plant in the South African context, were two of the primary reasons the respondents opted for an explicit exclusion of maize as a feedstock. Findings from quantitative analysis revealed that the profitability of the bioethanol plant was largely influenced by the prices of feedstock and bioethanol. The 2016 fiscal year indicated the worst case scenario in terms of economic viability of the bioethanol. The astronomically high price of maize due to drought (R5000/ton) rendered the project unprofitable as all of the economic indicators were negative. In the same marketing year, however, the trade balance of maize was positive, indicating a surplus. The study recommended that all of the surplus maize should be exported because it is not economically viable to build a bioethanol plant. The 2011 fiscal year indicated the best case scenario in terms of the economics of the project. This was due to the decrease in price of maize (R1726/ton) and a slight increase in the price of bioethanol. All of the economic indicators were positive, suggesting the benefits of investing in bioethanol production. It was recommended that under normal conditions of maize production in South Africa, a bioethanol plant can be operated simultaneous to maize exportation to other countries without compromising food security, because a maize-fed bioethanol plant uses only a small proportion of maize (14.3%) from the total volume of maize that is exported. Furthermore, it generates more revenue (99.9%) compared to the maize export revenue. It was recommended that sensitivity analysis should be conducted in a holistic manner whereby all variables in the economic model must be adjusted to assess the impact of each on the overall project profitability.
10

Climate impact assessment of coupling biogas production to agricultural and energy systems: crop variety of Solaris energy tobacco in Marble Hall, South Africa

Öckerman, Frode January 2016 (has links)
In the context of global energy shortage and climate change, developing local biogas plants coupled with agricultural systems can become an important strategy for cleaner rural energy and sustainable agriculture. In this research, a Life Cycle Assessment (LCA) method was applied to compare the climate impact of two essentially different systems: 1) Scenario I: an agricultural system based on the cultivation of 11 hectares of energy tobacco primarily for seed production; 2) Scenario II: a hypothetical Scenario Investigating the climate impact concerned with a crop variety – a higher yielding variety cultivated for both seed and biomass - and introducing biogas production. Both scenarios focus on the energy tobacco biomass residues. The overall aim of the study was to evaluate the climate impact of these two scenarios in the agricultural and energy system in Marble Hall, Limpopo Province, South Africa. The biogas was used for electricity production, replacing coal-based electricity on the grid. Biomass residues were chosen as feedstock for biogas production since this crop presently receives much attention in the region as the oily seeds can be used to produce sustainable jet fuel. Results from the modelling show that Scenario II would provide a positive climate impact: a 43% reduction of greenhouse gases compared to Scenario I. The higher yielding crop variety in Scenario II means that there is also potential to produce more sustainable jet fuel to replace conventional aviation fossil fuel. Taking this into account, the biogas scenario can reduce emissions by 79% compared to the base case. An analysis of the results indicates that there are several variables in the system model that are uncertain and sensitive to change, proving that more research is necessary to make robust conclusions about the validity of the presented results.

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