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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.
61

Herbaceous biomass production following pea harvest

Doyle, Kristine. January 1982 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 41-47).
62

Energy planning and policies in nepal /

Shrestha, Rita. January 1997 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 116-121).
63

Energy policy in the Republic of China and Japan, 1970-1985 a comparative examination of energy politics and policies /

Wang, Han-Kuo. January 1987 (has links)
Thesis (Ph. D.)--North Texas State University, 1987. / Includes bibliographical references (leaves 315-337).
64

Energy basis for Miami, Florida, and other urban systems

Zucchetto, J. January 1975 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Bibliography: leaves 241-247.
65

Systems analysis of Zimbabwe's industrial energy base

Maya, Ruzvidzo Shakespeare. January 1982 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 164-166).
66

Energy conservation at the Purnell School

Jones, William J William J., Meyer, James Wagner 02 1900 (has links)
No description available.
67

Improved solar energy collector system

Godon, S January 1978 (has links)
Abstract not available.
68

Empirical and behavioural economic applications to the energy sector

Klege, Rebecca Afua January 2020 (has links)
This thesis contributes to the energy literature by leveraging insights from empirical and experimental economics. The thesis presents four papers with a common goal of understanding specific themes in the energy sector namely: households energy use patterns, behavioural preferences among entrepreneurs operating energy businesses and applications of behavioural nudges to reduce energy use. The first paper set the tone for the two subsequent chapters. The paper: 'Energy Choices and Tenancy in Rwanda' examines the energy choice patterns of households based on their rental status and dwelling types. The fifth Integrated Household Living Conditions Survey (EICV5) conducted over one year, October 2016 to October 2017, together with a bivariate probit model is used. A heterogeneous analysis focused on gender and income differentiated impacts, as well as geographical differences based on the tenancy status of households, is further examined. The results signal that households energy choices in Rwanda differ by rental and dwelling types. The second and third papers ascertain the role of competition and risk preferences among entrepreneurs working in off-grid renewable energy microenterprises and its effects on business success in the context of including more women as entrepreneurs in the energy sector. Specifically, the second paper: 'Competition and Gender in the Lab vs Field: Experiments with Off-Grid Renewable Energy Entrepreneurs in Rural Rwanda' examines the gender differences in competitiveness and how this affects the business success of entrepreneurs operating renewable energy enterprises. Results from the economic experiments are compared to the day to day activities of the business. Findings show that female entrepreneurs are not less likely to compete and are not outperformed by male entrepreneurs. This stands in contrast to several studies, mostly conducted on university students of developed countries. The third paper: 'Risk attitudes, Gender and Business Performance Among off-grid Renewable Energy Entrepreneurs in Rural Rwanda' in a similar context examines the risk attitudes among entrepreneurs and its effect on the performance from a gender perspective. The study adopts a choice list experimental approach to elicit risk attitudes. The results indicate a strong risk aversion among entrepreneurs. The risk aversion found is higher for women compared to men. Entrepreneurs with high risk-taking abilities also tend to record better performance levels. The paper concludes that policies geared towards hedging against risk aversion in entrepreneurial programs may be vital in reducing gender gaps in business performance. The fourth paper: 'The power of nudging: Using feedback, competition and responsibility assignment to save electricity in a non-residential setting' answers the question 'can behavioural interventions achieve energy savings in non-residential settings where users do not face the financial consequences of their behaviour?' The paper relies on a randomized control trial and two behavioural interventions. Results show that behavioural nudges can be useful in reducing energy consumption in a non-residential environment.
69

Solar energy collection using vee-grooved surfaces

Kemper, Jens Peter January 1977 (has links)
Bibliography: pages 98-103. / The thesis presented is a study of the absorption characteristics of diffusely and specularly reflecting V-grooved surfaces. Concepts are developed for the so-called "apparent" absorptance of a V-groove cavity, as well as for the "effective" absorptance of a V-grooved surface. These concepts are formulated in closed form mathematical equations, which facilitate both the optimization of V-grooved surfaces and their engineering design. In order to verify the theoretical analysis, experiments are carried out on 34 V-grooved brass specimens. In addition, the experiments are meant to provide information about the behaviour of such surfaces used for solar energy collection. For that purpose, the specimens are exposed to simulated sunlight, and their effective absorptances, as well as their absorption efficiencies, are determined by a calorimetric method. The highlights among the results are: 1. V-grooves - carefully optimized and applied to a solar energy absorbing surface - can raise its absorptance almost to unity and improve its absorption efficiency. 2. Best performances at elevated temperatures can be expected from using metal surfaces which are provided with specular V-grooves having a small groove angle (< 30⁰). 3. The optimal groove angle is dependent on (1) the reflection properties of the surface, (2) the absorptance of the surface material, and (3) the ratio of groove depth to width of land which occurs between grooves.
70

Estimating the performance of hybrid (monocrystalline PV - cooling) system using different factors.

Zeinaldeen, Laith Akeelaldeen 01 December 2020 (has links)
AN ABSTRACT OF THE DISSERTATION OFLaith A. Zeinaldeen, for the Doctor of Philosophy degree in AGRICULTURAL SCIENCES – Renewable Energy, presented on November 2, 2020, at Southern Illinois University Carbondale.TITLE: ESTIMATING THE PERFORMANCE OF HYBRID (MONOCRYSTALLINE PV - COOLING) SYSTEM USING DIFFERENT FACTORSMAJOR PROFESSOR: Dr. Logan O. ParkAmbient temperature significantly affects photovoltaic (PV) panel performance. High temperature reduces PV panel efficiency, fill factor, and maximum power, driving up solar electrical system investment return period by increasing startup cost. Using a proper cooling system to cool down the PV panel temperature, especially during the summer season, will improve the PV panel performance, enhance its longevity, and accelerate the startup cost recovery to the solar electrical system. This dissertation presents two studies about monocrystalline PV panels. The studies used two general objectives: (i) study the best cooling period and water nozzle type to improve the monocrystalline PV panel output; and (ii) evaluating the performance of the monocrystalline PV panel using different cooling systems, other water pump discharge, and various water types during different times of day. In the first study (chapter 4), an experiment was conducted during July 2018 to determine Effect of using different cooling periods and different water nozzle types on the fill factor, efficiency, and the maximum power of monocrystalline PV panel. This experiment used two factors. The first factor was the cooling periods, which included three levels of PV panel cooling periods (5, 15, and 30 minutes). The second factor was water nozzle type: hollow cone and flat fan.In the second study (chapters 5, 6, and 7), an experiment was conducted during July and August 2018 to determine Effect of using different factors on the performance of monocrystalline PV panel at a site belong to the College of Agriculture – Southern Illinois University in Carbondale, IL. This experiment used four factors. The first factor was the time of day, the second factor was the cooling system, the third factor was the water pump discharge, and the fourth factor was the water type. The present studies' principal findings were: (i) the first experiment, the 15 minutes cooling period achieved the highest PV panel fill factor (0.795). In comparison, the 30 minutes cooling period reached the highest panel efficiency (18.6%) and maximum power (92.5 Watt). In contrast, the 5 minutes cooling period achieved the lowest PV panel fill factor (0.720), lowest panel efficiency (12.9%), and most insufficient panel maximum power (63.5 Watt). The hollow cone water nozzle achieved the highest panel fill factor (0.783), highest panel efficiency (16.60%), and the most elevated PV panel maximum power (82.8Watt). Interaction between the cooling and water nozzle types was non-significant on PV panel fill factor, significant on panel efficiency, and highly significant on PV panel maximum power. The interaction results between the cooling period and nozzle type demonstrate that the hollow cone nozzle with 30 minutes cooling period achieved the highest panel fill factor, highest panel efficiency, and the most elevated panel maximum power. The flat fan with a 5-minute cooling period achieved the lowest fill factor, lowest panel efficiency, and most insufficient panel maximum power. Tukey test results showed a highly significant difference (P < 0.0001) between the cooling period and the control treatment, and between the nozzle type treatment and the control treatment on panel fill factor, efficiency, and panel maximum power. Cooling periods have the most considerable effect on panel fill factor, panel efficiency, and maximum panel power, followed by the nozzle type. (ii) The second experiment results showed, the first cooling system (HC1) achieved the highest PV panel maximum power (77.0Watt), highest fill factor (0.745), highest PV panel efficiency (14.75%), highest average net energy (39.5Wh), highest PV panel energy (189.0 Wh) and highest average power gain (34.6Watt) comparing to the rest of the cooling systems. In comparison, the fourth (FtF2) achieved the lowest maximum power (58.0 Watt), lowest fill factor (0.653), lowest average efficiency (11.6%), lowest average net energy (-4.0Wh), lowest average energy (147.5Wh), and lowest average power gain (17.5 Watt). The fifth cooling system (SP) achieved the least average water consumption (2.0 L / hr.), while the second cooling system (HC2) achieved the highest average water consumption (39.0 L / hr.). The medium water pump discharge (M) produced the most elevated PV panel maximum power (67.6 Watt), highest fill factor (0.709), highest average PV panel efficiency (13.28%), highest average PV panel net energy (18 Wh), highest average PV panel energy (169.0Wh) and the highest average PV panel power gain (25.9Watt). High water pump discharge (H) achieved the lowest maximum power (63.8Watt), lowest average panel efficiency (12.48%), lowest average net energy (7.5Wh), lowest average panel energy (159.5Wh), and the lowest average power gain (21.8 Watt). The low water pump discharge (L) achieved the lowest panel fill factor (0.698). Lake water achieved the highest panel maximum power (66.1Watt), lowest PV panel fill factor (0.698), highest panel efficiency (12.94%), lowest net energy (12.8 Wh), highest panel energy (165.2 Wh), and lowest power gain (23.5Watt). In contrast, city water achieved the most elevated PV panel fill factor (0.708), most insufficient panel maximum power (64.8 Watt), highest average PV panel net energy (14.8 Wh), lowest efficiency (12.62%), highest average PV panel power gain (24.25 Watt) and lowest panel energy (162.1 Wh). Tukey post hoc difference testing showed highly significant differences (P < 0.0001) between the time of day, cooling system, water pump discharge, water type treatments, and their control treatment on PV panel maximum power, fill factor, panel efficiency, panel net energy, panel energy, power gain, and the system water consumption. The cooling system has the most considerable effect on PV panel maximum power, panel fill factor, panel efficiency, panel net energy, panel energy, panel power gain, and the system water consumption. In general, using the cooling system improves the PV panel performance through enhancing the PV panel efficiency, maximum panel power, panel fill factor, panel net energy, panel energy, and PV panel power gain. Keywords: Cooling system, cooling periods, water pump discharge, water type, time of day, efficiency, maximum power, fill factor, net energy, panel energy, PV panel power gain, and cooling system water consumption.

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