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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.
301

Modelling, simulation and control of photovoltaic converter systems

Gow, John A. January 1998 (has links)
The thesis follows the development of an advanced solar photovoltaic power conversion system from first principles. It is divided into five parts. The first section shows the development of a circuit-based simulation model of a photovoltaic (PV) cell within the 'SABER' simulator environment. Although simulation models for photovoltaic cells are available these are usually application specific, mathematically intensive and not suited to the development of power electronics. The model derived within the thesis is a circuit-based model that makes use of a series of current/voltage data sets taken from an actual cell in order to define the relationships between the cell double-exponential model parameters and the environmental parameters of temperature and irradiance. Resulting expressions define a 'black box' model, and the power electronics designer may simply specify values of temperature and irradiance to the model, and the simulated electrical connections to the cell provide the appropriate I/V characteristic. The second section deals with the development of a simulation model of an advanced PVaware DC-DC converter system. This differs from the conventional in that by using an embedded maximum power tracking system within a conventional linear feedback control arrangement it addresses the problem of loads which may not require the level of power available at the maximum power point, but is also able to drive loads which consistently require a maximum power feed such as a grid-coupled inverter. The third section details a low-power implementation of the above system in hardware. This shows the viability of the new, fast embedded maximum power tracking system and also the advantages of the system in terms of speed and response time over conventional systems. The fourth section builds upon the simulation model developed in the second section by adding an inverter allowing AC loads (including a utility) to be driven. The complete system is simulated and a set of results obtained showing that the system is a usable one. The final section describes the construction and analysis of a complete system in hardware (c. 500W) and identifies the suitability of the system to appropriate applications.
302

SunSpot: A Spatial Decision Support Web-Application for Exploring Urban Solar Energy Potential

Blakey, Andrew January 2013 (has links)
The growing necessity for meaningful climate change response has encouraged the development of global warming mitigation and adaptation initiatives. Urban solar energy generation is one opportunity that has been investigated by numerous cities through various solar potential Web-applications. However, as solar feasibility can vary considerably across a small geographic area due to variations in local topography and feature shading, there is no one-size-fits-all solution to be implemented. This thesis investigates how a Web-based spatial decision support system (SDSS) can enable non-experts to explore urban solar feasibility and, to a lesser extent, issues related to urban heat. First, a conceptual framework is developed that investigates the linkages between SDSS, Web technologies, public participation, volunteered geographic information, and existing green energy initiatives. This framework identifies the relevance between these fields of study as well as a number of opportunities for improving on past work and taking advantage of new technical capabilities. Second, in order to test the opportunities identified, SunSpot was developed. This Web-SDSS investigates rooftop solar feasibility as well as land cover and surface temperature dynamics relating to the urban heat-island effect in Toronto, Ontario, Canada. A number of solar resource datasets were developed in order to facilitate the decision making capabilities of SunSpot. This was done using a combination of different topographical data sources, atmospheric data, and a raster-based irradiance model called Solar Analyst. Third, a number of in-person workshops were conducted to obtain feedback on SunSpot’s usability and ability for users to understand the visual layers and results. Finally, this feedback was analyzed to identify the successes and challenges of SunSpot’s capabilities and design. This revealed a number of recommendations for further development of SunSpot, as well as opportunities for future research relating to the development of local scale solar resource data and the development of similar Web-SDSS applications.
303

Solar Energy Potential Analysis at Building Scale Using LiDAR and Satellite Data

Aguayo, Paula 23 May 2013 (has links)
The two main challenges of the twenty-first century are the scarcity of energy sources and global warming; trigged by the emission of greenhouse gases. In this context, solar energy became increasingly relevant. Because it makes optimal use of the resources, minimizes environmental impacts, and is sustainable over time. However, before installing solar panels, it is convenient pre-assessing the amount of energy that a building can harvest. This study proposes a methodology to semi-automatically generate information a building scale; on a large area. This thesis integrates airborne Light Detection and Ranging (LiDAR) and WoldView-2 satellite data for modelling the solar energy potential of building rooftops in San Francisco, California. The methodology involved building detection solar potential analysis, and estimations at building scale. First, the outline of building rooftops is extracted using an object-based approach. Next, the solar modelling is carried out using the solar radiation analysis tool in ArcGIS, Spatial Analyst. Then, energy that could potentially be harvested by each building rooftop is estimated. The energy estimation is defined in economic and environmental terms.
304

A solar climate control system using a water film flow to conserve energy in greenhouses /

Ménard, Odette January 1991 (has links)
One of the greatest problems encountered in greenhouses and buildings with large glazing is control of the internal atmosphere. The inherent characteristic of these buildings to act as solar collectors is to be used effectively for collecting and storing the excess solar energy. A new type of glazed roof, a Solar Climate Control roof system, was designed as a means to cool the interior environment of the greenhouses during the daytime and to heat during the nighttime or on overcast days. / A heat exchanger-storage system, using water as a thermal mass is included in the design of the Solar Climate Control system. A film of water flows on the inner surface of the roof and absorbs the direct solar heat radiation, acting then as a cooling agent. The energy absorbed may be reused for nighttime heating. / An efficient water dispersion pipe for the Solar Climate Control system was developed. The use of a soap solution rather than water alone for the Solar Climate Control water film system permitted a significant reduction in pumping rate and improved uniformity of the film. / A computer simulation model was run to determine the energy loads for both a conventional (double glazed roof) greenhouse and one equipped with the Solar Climate Control system. The Solar Climate Control system shows low operating cost and very good efficiency in heat removal.
305

A study of a solar still coupled with a greenhouse.

Tran, Van-Vi January 1974 (has links)
No description available.
306

A Detailed Performance Comparison of PV Modules of Different Technologies and the Implications for PV System Design Methods

A.carr@aip.org.au, Anna Judith Carr January 2005 (has links)
In designing any power generation system that incorporates photovoltaics (PV) there is a basic requirement to accurately estimate the output from the proposed PV array under operating conditions. PV modules are given a power rating at standard test conditions(STC) of 1000Wm-2, AM1.5 and a module temperature of 25 °C, but these conditions do not represent what is typically experienced under outdoor operation. It is well known that different PV technologies have different seasonal patterns of behaviour. These differences are due to the variations in spectral response, the different temperature coefficients of voltage and current and, in the case of amorphous silicon (a-Si) modules, the extra effect of photo-degradation and thermal annealing. In this study a novel method has been used to obtain highly accurate energy output data from six different PV modules representing five different technologies: Single crystal silicon (c-Si). Poly-crystalline silicon (p-Si) (2 modules). Triple junction amorphous silicon (3j, a-Si). Copper indium diselenide (CIS). Laser grooved buried contact (LGBC, c-Si) crystalline silicon. This data set includes all the associated meteorological parameters and back-of-module temperatures. The monitoring system allows the simultaneous measurement of six different modules under long-term outdoor operation, which in turn allows a direct comparison of the performance of the modules. Each of the modules has been deployed for at least one year, which provides useful information about the seasonal behaviour of each technology. This data set ultimately provides system designers and consumers with valuable information on the expected output of these different module types in climates like that of Perth, Western Australia. The second part of the study uses the output data collected to assess and compare output predictions made by some currently available photovoltaic performance prediction tools or methods. These range from a generalised approach, as used in the Australian Standards, to the commercially available software packages that employ radiation, thermal and PV models of varying complexities. The results of these evaluations provide very valuable information, to PV consumers, about how complex PV output prediction tools need to be to give acceptable results.
307

Modeling three reacting flow systems with modern computational fluid dynamics /

Price, Ralph J., January 2007 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University. Dept. of Chemical Engineering, 2007. / Includes bibliographical references (p. 163-169).
308

The role of the Department of Defense (DoD) in solar energy research, development and diffusion

Benham, William T. Cabral, Noel J. January 2008 (has links) (PDF)
"Submitted in partial fulfillment of the requirements for the degree of Master of Business Administration from the Naval Postgraduate School, June 2008." / Advisor(s): Dew, Nicholas ; Ventresca, Marc. "June 2008." "MBA professional report"--Cover. Description based on title screen as viewed on August 7, 2008. Includes bibliographical references (p. 91-97). Also available in print.
309

Fabrication and analysis of patterned and planar CdTe-based solar cells

Rodríguez Chávez, Mario Arturo, January 2008 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
310

Application of solar energy at Ohio highway rest areas

Pannila, Lankajith C. January 1993 (has links)
Thesis (M.S.)--Ohio University, November, 1993. / Title from PDF t.p.

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