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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.
441

Studium tepelných poměrů a vhodných materiálů pro konstrukci energetického zásobníku pro dlouhodobé ukládání energie v podmínkách klimatu ČR / Study of thermal conditions and the appropriate materials for construction of the energy reservoir for long term storage in the conditions of climate CR

Bukvová, Veronika January 2018 (has links)
Presented work deals with appropriate ways of storing thermal energy and selection of materials for a high capacity storage unit. The thesis describes technologies currently used for long-term storage of thermal energy, the structural arrangement of the thermal unit, physical properties of the materials usable for construction of high-temperature storage units and the utilization of these materials. The thesis also describes the measuring procedure of the material characteristics and the method of evaluation. Size of the solar collector and the required volume of the storage for heat supplying of the selected building in the climatic conditions of the Czech Republic were designed.
442

Vývoj komplexního simulátoru slunečního záření a jeho spolupráce s FV modulem / Development of the complex simulator of the solar irradiance and its cooperation with the PV module

Petrov, Roman January 2018 (has links)
The main point of this thesis is the extension of the complex solar radiation simulator, the creation of new functionalities, and the cooperation of this complex simulator with the PV power plant. This work builds on the work done in the area of solar radiation modeling. The thesis deals with the continuation, or improvement of some shortcomings, removing shortcomings, such as fixing the beginnings and ends of the simulation, correcting the calculation of sunrise and sunset, but also adding different types of clouds, combinations of different preset cloud situations, or data input, and more. These deficiencies are found in the bachelor's thesis "Complex Simulator of the solar irradiance", and PSCAD is the main tool in this work. Another important point of this work is the realization of the simulation where an improved solar radiation simulator works in cooperation with a model of a photovoltaic panel or a PV power plant, respectively. It has different operating states created in PSCAD. These include, for example, cloud crossings, both over the entire power plant and only partial. In addition, there are experiments that prove the fact that the direction of the incoming cloud plays a role in the power of the PV power plant.
443

Měření a regulace počítačem řízených solárních systémů: Vizualizace energetických systémů / Measuring and regulation of computer controlled solar systems: Vizualization of energetic systems

Vlčnovská Kotlíková, Silvie January 2008 (has links)
This work is oriented on study and evaluation of performance of real operating solar system. There was made analysis of actual technological unit and there was suggested mode of measuring of nodal parameters. There was made interconnection between the head operating unit of the solar system and the web server. And there was prepared software for grafical image of time and temperature dependence and for data transfer to ready web application. It primarily talks about increase of efficiency of real technological unit through regulating of parameter that is using up of accumulated energy.
444

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.
445

Termoelektrický solární generátor / Thermo-electric solar generator

Kočvárek, Ondřej January 2008 (has links)
The introduction of this work is devoted to the description of physical principals and condtruction of modern semiconductor thermoelectric transformers. This work describes thein basic characters and the most commonly used materials for thein production. Further, it mentions the basic principals and physical effects that describe the thermoelectric conversion of energy and the nondestructive method for establishing the basic material characteristics of thermoelectric transformers. The substantiv part of this work is the measuring of the material’s characteristics of the accessible thermoelectric elements through the medium of experimental measuring network. The optimal construction of thermoelectric solar generators used for individual thermoelectric elements are designed based on the taken measurements and the evaluation of material’s characteristics of the observed thermoelectric elements.
446

Vyhodnocení ekonomické efektivnosti solárního systému / Analysis of the economic efficiency of a solar system

Mikl, Antonín January 2009 (has links)
The Master’s thesis deals with the processing of solar thermal systems for heating hot water, outdoor swimming pool and heating selected house. Introduces us how we can use the sun for the production of thermal energy through solar collectors. Furthermore, the basic components of the solar system and the types of collectors used. After this summary on the present state be the calculation of the system and fixing the price of the investment. The economic part of the evaluate if this system to invest, eventually appoint a return on investment.
447

Automatické vyhodnocování spektra slunečního záření / Automatic evaluation of the solar spectrum

Vlček, Josef January 2015 (has links)
This master’s thesis deals with properties of a solar radiation, measurement of a solar spectrum and standard IEC 60904-9, which defines the requirements for a solar simulator. Solar simulators are classified as A, B or C for each of the three categories based on criteria of spectral distribution match, irradiance non-uniformity on the test plane and temporal instability. The goal of this thesis was creation software for automatic evaluation of a solar spectrum. Software was created in Matlab application and its function is to determine class of solar spectral match with spectrum AM1.5. The last part contains a measurement of various solar sources and using the created software was determined its spectral match with spectrum AM1.5.
448

Optimalizace využití solární energie v rodinném domě / Optimising the use of solar energy in the family house

Letochová, Jana January 2014 (has links)
This thesis is focused on solar energy as an alternative sustainable energy source and its use in family homes. The first part focuses on possible connections of solar energy systems and their design using software simulations. The second part consists of a design for the preparation of hot water in the family home. Finally, a comparison of the efficiency of the set collector according to different calculation methods is included.
449

Návrh systému řízení a diagnostiky ohřevu vody s využitím solární energie / Design of system control and diagnostics water heating using solar energy

Kužel, Kristián January 2013 (has links)
This thesis deals with problems related to heating of hot service water. It focuses on solar water heating, describes individual types of solar panels and summarizes the existing information about solar water heating. It demonstrates actual problems of solar system solution on a specific example of a two-generation family house, where it analyses possibilities of diagnostics and control of such system. It also deals with suggestions of possible expansion of the current solar system.
450

Computational study of low index surface of an anatase TiO2 doped with ruthenium (Ru) and strontium (sr) for application in Dye sensitized solar cells

Nemudzivhadi, Hulisani 18 May 2019 (has links)
MSc (Physics) / Department of Physics / Titanium dioxide (TiO2) is considered to be an ideal semiconductor for photocatalysis because of its high stability, low cost and safety towards both humans and the environment. Doping TiO2 with different elements has attracted much attention as the most important way of enhancing the visible light absorption, in order to improve the efficiency of the dye sensitized solar cells (DSSCs). In this study, first principle density functional theory was used to investigate electronic and optical properties of bulk anatase TiO2, undoped, and ruthenium (Ru) and strontium (Sr) doped anatase TiO2 (1 0 0) surface. Two different doping approaches i.e., substitutional and adsorption mechanisms were considered in this study. The results showed that absorption band edges of Ru and Sr-doped anatase TiO2 (1 0 0) surface shift to the long wavelength region compared to the bulk anatase TiO2 and undoped anatase TiO2 (1 0 0) surface. Also, the results revealed that the band gap values and the carrier mobility in the valence band, conduction band and impurity energy levels have a synergetic influence on the visible-light absorption and photocatalytic activity of the doped anatase TiO2 (1 0 0) surface. Furthermore, according to the calculated results, we propose the optical transition mechanisms of Ru and Sr-doped anatase TiO2 (1 0 0) surface. Thus, we conclude that the visible light response of TiO2 can be modulated by doping with both Ru and Sr. However, Sr-doped system shows higher photocatalytic activity than the Ru-doped system. The study has successfully probed the interesting optical response mechanism of TiO2 (1 0 0) surface. / NRF

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