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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

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.
2

Solarenergie in Kenya : meteorologisch-klimatologische, technische und wirtschaftliche Potenziale einer dezentralen photovoltaischen Stromerzeugung zur Basisenergieversorgung ländlicher Haushalte (mit Beispielen aus der Central Province) /

Glowatzki, Matthias, January 2001 (has links)
Thesis (doctoral)--Universität, Trier, 2001. / Includes bibliographical references.
3

Identification and development of novel optics for concentrator photovoltaic applications

Shanks, Katie May Agnes January 2017 (has links)
Concentrating photovoltaic (CPV) systems are a key step in expanding the use of solar energy. Solar cells can operate at increased efficiencies under higher solar concentration and replacing solar cells with optical devices to capture light is an effective method of decreasing the cost of a system without compromising the amount of solar energy absorbed. CPV systems are however still in a stage of development where new designs, methods and materials are still being created in order to reach a low levelled cost of energy comparable to standard silicon based photovoltaic (PV) systems. This work outlines the different types of concentration photovoltaic systems, their various design advantages and limitations, and noticeable trends. Comparisons on materials, optical efficiency and optical tolerance (acceptance angle) are made in the literature review as well as during theoretical and experimental investigations. The subject of surface structure and its implications on concentrator optics has been discussed in detail while highlighting the need for enhanced considerations towards material and hence the surface quality of optics. All of the findings presented contribute to the development of higher performance CPV technologies. Specifically high and ultrahigh concentrator designs and the accompanied need for high accuracy high quality optics has been supported. A simulation method has been presented which gives attention to surface scattering which can decrease the optical efficiency by 10-40% (absolute value) depending on the material and manufacturing method. New plastic optics and support structures have been proposed and experimentally tested including the use of a conjugate refractive-reflective homogeniser (CRRH). The CRRH uses a reflective outer casing to capture any light rays which have failed total internal reflection (TIR) due to non-ideal surface topography. The CRRH was theoretically simulated and found to improve the optical efficiency of a cassegrain concentrator by a maximum of 7.75%. A prototype was built and tested where the power output increase when utilising the CRRH was a promising 4.5%. The 3D printed support structure incorporated for the CRRH however melted under focused light, which reached temperatures of 226.3°C, when tested at the Indian Institute of Technology Madras in Chennai India. The need for further research into prototyping methods and materials for novel optics was also demonstrated as well as the advantages of broadening CPV technology into the fields of biomimicry. The cabbage white butterfly was proven to concentrate light onto its thorax using its highly reflective and lightweight wings in a basking V-shape not unlike V-trough concentrators. These wings were measured to have a unique structure consisting of ellipsoidal pterin beads aligned in ladder like structures on each wing scale which itself is then tiled in a roof like pattern on the wing. Such structures of a reflective material may be the answer to lightweight materials capable of increasing the power to weight ratio of CPV technology greatly. Experimental testing of the large cabbage white wings with a silicon solar cell confirmed a 17x greater power to weight ratio in comparison to the same set up with reflective film instead of the wings. An ultrahigh design was proposed taking into account manufacturing considerations and material options. The geometrical design was of 5800x of which an optical efficiency of either ~75% with state of the art optics should produce and effective concentration of ~4300x. Relatively standard quality optics on the other hand should give an optical efficiency of ~55% and concentration ratio ~3000x. A prototype of the system is hypothesised to fall between these two predictions. Ultrahigh designs can be realised if the design process is as comprehensive as possible, considering materials, surface structure, component combinations, anti-reflective coatings, manufacturing processes and alignment methods. Most of which have been addressed in this work and the accompanied articles. Higher concentration designs have been shown to have greater advantages in terms of the environmental impact, efficiency and cost effectiveness. But these benefits can only be realised if designs take into account the aforementioned factors. Most importantly surface structure plays a big role in the performance of ultrahigh concentrator photovoltaics. One of the breakthroughs for solar concentrator technology was the discovery of PMMA and its application for Fresnel lenses. It is hence not an unusual notion that further breakthroughs in the optics for concentrator photovoltaic applications will be largely due to the development of new materials for its purpose. In order to make the necessary leaps in solar concentrator optics to efficient cost effective PV technologies, future novel designs should consider not only novel geometries but also the effect of different materials and surface structures. There is still a vast potential for what materials and hence surface structures could be utilised for solar concentrator designs especially if inspiration is taken from biological structures already proven to manipulate light.
4

Web rozhraní malé sluneční elektrárny / Solar Powerstation Web Interface

Škvařil, Radek January 2008 (has links)
This thesis is focused on practical usage of solar energy in photovoltaic systems and on the Fronius product portfolio. It is also focused on implementation of web interface for modular solar photovoltaic Fronius powerstations system. It is purposed on displaying statistic data, drawing charts and solar system monitoring. This system is desired to act autonomic and self-configurable. System will be implemented using the PHP5, MySQL4 technologies and object oriented programming technique.
5

Implementation and validation of a design model for photovoltaic water pumping system (PVPS).

Merlini, Maurizio January 2012 (has links)
Desertification is one of the main problems plaguing the Chinese countryside. The main cause is the heavy overgrazing of pastures and in this context the irrigation can be a solution to the problem. As regard the existent irrigations systems, pumps are driven manually or by diesel engines. Actually the use of electric motors would be a better solution for the irrigation development, but the lack of the access to electric network for the isolated rural areas represents a great obstacle. Therefore the use of PV stand-alone systems to produce the electricity for the motor-pumps (PVPS- Photovoltaic Pumping Systems) represents a both economic and technical good solution. However the weak point for PVPS diffusion is lack of tools to design these systems and predict their performances. This thesis work wants to provide a sizing software and the technical guidelines to select the suitable components for a PVPS. The developed sizing method has been validated applying it to two real cases where PVPS were already existing. Then, the obtained results have been compared with the characteristics of the real PVPS. The reliability of the design procedure has been verified, observing the similarity between the calculated outputs and the respective real values. Finally simulations have been done using the designed PVPS. The scope of those simulations has been to add some technical recommendations useful for the PVPS designer. The influence of the total head variations on the pumping performance and also the effect of the motor-pump subsystem choice on the final power size of PV array have been investigated.
6

Evaluation of a Minute Synthesis Irradiation Model for the Frequency Containment Reserve : Disturbance down-regulation market

Luz Pedemonte, Pablo Omar January 2022 (has links)
With the increase in energy demand, and therefore, in energy generation, new high voltage direct current export links and overseas connections of large amounts of power are being introduced. These new links are subject to possible malfunction or failures, which may causea substantial frequency increase in the power system. The need of restorative measurements for over-frequencies is then necessary to regulate this probable imbalance. A new ancillary market product for frequency down-regulation is then being introduced. The Frequency Containment Reserves – Disturbances for downregulation is a service used to handle overfrequencies in the power system. The ancillary market has been historically dominated by hydro, however, with the local plans that set goals to reach 100 % renewable electricity production by the year 2040, ineluctably solar and wind will be occupying a large share of the energy generation, thus the amount of renewable resources to provide ancillary services will increase as well. Nevertheless, requirements to participate in the ancillary market are strict, and renewables face challenges such as unpredictable power generation, making forecasting tools essential for their participation. In this thesis, through the literature and research of an emerging field, the synthetic solar irradiance, an algorithm with adjusted parameters is replicated with the objective of downscaling solar irradiance presumptive-forecasts from 15-minute intervals to 1-minute intervals. An updated clear-sky model, and weather categorization method is used as input to improve the results of the synthesis. A year evaluation with a method to detect irradiance dips is used to evaluate the algorithm. The result of this study contributes with positive outputs. The introduction of this secondary tool to estimate higher resolution irradiance variability data proves to obtain, at 57 % of the point-to-point critical cases examination, an over-estimation of the measured irradiance. This, in turn, grants the actors that participate with solar power the option to adjust the bidding strategy process in the ancillary market accordingly to the output of this tool.
7

Ocenenie fotovoltaickej elektrárne / Evaluation of a Photovoltaic Power Plant

Hrubjáková, Martina January 2011 (has links)
The aim of this master's thesis is the evaluation of a company, of which the purpose of its existence is the development and running of a photovoltaic power plant. The estimated value refers to December 31st, 2011 and is determined for the purpose of potential sale of the company. The thesis consists of theoretical part, which includes determination of basic terms and concept of the evaluation process, and the practical application of theoretical knowledge on the specific company. A brief presentation of the company is followed by the strategic analysis, which identifies the most important opportunities and threats for the company in the future. Together with a review of previous company's financial results it represents the initial point for the preparation of a financial plan. The final part of the thesis includes the evaluation of the company in two versions. The first one is based on the assumption of termination company's activity after a specific period. The second one is based on the going-concern principle. The statement about the value of the company is supplemented by the valuation of the investment project.
8

Le photovoltaïque, une « innovation verte » à l'épreuve du droit : analyse synthétique et critique du cadre juridique photovoltaïque visant le particulier à la Réunion / No English title available

Kamkar, Paradis 06 November 2015 (has links)
Sous l'impulsion de l'Union européenne et de l'ouverture des marchés, le droit de l'énergie a considérablement évolué ces dix dernières années. Les textes en matière d'énergie solaire photovoltaïque se sont amplifiés depuis la loi « Pope » jusqu'aux lois « Grenelle I » et « Grenelle II », et récemment avec la loi n° 2015-992 du 17 août 2015 relative à la transition énergétique pour la croissance verte, suivies de nombreux décrets pour leur application et une jurisprudence de plus en plus abondante en la matière. Il en résulte un ensemble considérable de textes évolutifs et complexes dont l'accès reste difficile à appréhender et à appliquer. Cette instabilité des règles régissant la matière – certes inévitable au regard des nécessaires changements requis par toute innovation – est source d'insécurité juridique et s'avère extrêmement déstabilisante pour les acteurs du secteur en quête de visibilité. En outre, l'installation d'une centrale de production d'électricité photovoltaïque au sein de son habitation, est à la fois un projet d'investissement et une opération de construction immobilière, qui exige des garanties tant sur le plan financier qu'au niveau de la construction (sûretés et assurances) pour permettre de mieux maîtriser les risques et rassurer les parties au projet. Néanmoins, les nombreux freins contractuels, administratifs et financiers ralentissent le développement du photovoltaïque et se heurtent aux ambitions de promouvoir cette « électricité verte » sur l'ensemble du territoire et notamment parvenir à l'autonomie énergétique de l'île de La Réunion. Ainsi, cette étude présente et analyse le droit de l'énergie photovoltaïque, visant notamment le particulier à La Réunion, sous ses différents angles (fiscal, financier, contractuel, administratif, urbanistique, des responsabilités) – à jour des textes les plus récents – et en explicite les modalités d'application à la lumière des multiples textes réglementaires, législatifs, guides professionnels et de la jurisprudence, que ce soit celle des tribunaux ou des autorités de régulation. / Facing a weakening photovoltaic market and a sector already bedeviled recently by a huge increase of legal texts, private investors decrease. This thesis tackles legal framework concerning photovoltaic energy in Reunion Island. This will include the analysis of fiscal incentives such as investment grants and tax preferences, as well as more general environmental policy instruments (feed-in-tariffs and renewable subsidies and grants). Moreover, this will include the analysis of contracts such as loan agreement, sale contract, lease agreement and connection/Commissioning contracts, as well as more environmental aspect. At last, risks, insurances, liability comprising legal proceedings and guarantees will be studied in this thesis.
9

Efektivnost provozu fotovoltaických generátorů / Operational efficiency of photovoltaic generators

Koval, Filip January 2008 (has links)
Objective of master’s thesis theoretical part is especially to illustrate influence of operation conditions, such as solar radiation, temperature or pollution of photovoltaic generator active area, on load and power characteristics of photovoltaic generator, or more precisely on photovoltaic conversion efficiency. Possible variants of increasing effectivity of using photovoltaic generator are explored, such as solar radiation concentration, photovoltaic generator active area cooling or aplication of optimalization circuit. Pivotal part of master‘s thesis is focused on experimental device practical realisation, concretely type MSQ36-10 photovoltaic generator with oriented concentrators of solar radiation. Practical realisation includes design of master‘s thesis experimental part construction with subsequent design of photovoltaic generator motion cycle necessary for adequate simulation of configuration variants solved using single testing photovoltaic generator. Description of own experimental device construction with list of measuring places used in task takes up. It is used automatic monitoring system working as independent measurement task for required values measuring and consecutive data collecting. It is done in two phases. First phase is measurement of all required values, in second phase measurement with attached optimalization circuit is made. Optimalization circuit sets best working point of photovoltaic generator according to actual working conditions. Master‘s thesis intention is experimental verification of solar radiation concentrators application convenience, orientation of photovoltaic generator or its mutual combination, namely using type MSQ36-10 photovoltaic generator. Objective is evaluation of reached energetic gain for all experimental device layouts in variable operating conditions.

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