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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.
81

Návrh technického provedení FVE včetně systému řízení pro komerční objekt v souladu s platnými pravidly pro program ÚSPORY ENERGIE - FVE / Photovoltaic System Proposal for Commercial Building in Accordance with Applicable Rules for Energy Savings Program

Zeman, Daniel January 2018 (has links)
Main purpose of the thesis is to create proposal of the photovoltaic hybrid system for commercial building in accordance with applicable rules for energy savings program. The introductory part of the thesis describes the rules regarding the photovoltaic system parts. The next part of the thesis describes the available technical solution for realization of the photovoltaic system design and the possibilities of electric energy accumulation in these systems and how to deal with power overflows using the power flow controller and what is the negative impacts on the distribution network when switching the connected load. In the next part the design of the PV system is carried out according to the valid assumptions described in the theoretical part of the thesis. Verification of power flow controller and measurement results in UEEN laboratories. The last part of the thesis is an evaluation of the economic part of the proposed system.
82

Výpočtové hodnocení konstrukčních staviv z hlediska energetické náročnosti budovy / Computational structural assessment of buildings in terms of energy performance

Kaplan, Václav January 2017 (has links)
This thesis deals with the computational comparison of the energy performance of buildings of various construction materials. The work aims at assessing the building as a thermal system. The theoretical part describes the methods for calculating the energy performance of buildings. The experimental part of the work focuses on quantifying the heat consumption of specific buildings in terms of thermal stability and it is later compared with the results calculated in accordance with the applicable technical standards.
83

Systémy energeticky úsporných budov / Systems of energy efficient buildings

Šlampová, Kateřina Unknown Date (has links)
The topic of this diploma thesis is systems of energy efficient buildings with a focus on the building envelope. The first theoretical part describes the quantities that we consider when designing the building envelope. The second half of the theoretical part is with reference to the experimental part of the thesis focused on a special type of vertical perimeter structure, namely walls with live vegetation installed from the outside of the structure. The second, practical part of this work, deals with the design of heating and hot water supply for a multifunctional building. The design is elaborated in two variants - heating by means of radiators in the first variant and in the second variant by means of floor heating for residential units of the solved building. The third part define an experiment, which had the task of comparing the measured quantities on two types of vertical perimeter structures, namely a structure with growing greenery from the outside and an identical structure only without a layer of greenery. At the same time, the task was to check the possible influence of the applied greenery on heat losses, and thus the design of the heating system.
84

Akumulace energie v systémech TZB / Energy storage in Building services systems

Bílek, Martin January 2014 (has links)
The subject of this thesis is energy storage systems in building services. In the first part the theoretical acquaintance with the nature of energy storage. In the second part has two variants preparation hot water in an apartment building. In the third part of the test solution storage tank of hot water. Development of computational algorithms, comparison of calculation used and the final summary.
85

Transport elektrického náboje v tantalovém kondenzátoru / Transport of Electric Charge in Tantalum Capacitor

Pelčák, Jaromír January 2012 (has links)
The task of the thesis was studding of tantalum capacitors with solid electrolytes properties. Ta – Ta2O5 – MnO2 capacitor by its construction represents MIS structure, where tantalum anode has metal conductivity and MnO2 cathode is semiconductor. Isolation layer consists of tantalum pentoxide Ta2O5 with relative permitivity r = 27. Dielectric thickness is typically in range from 30 to 150nm. The capacitor charge is not only stored and accumulated on electrodes but also in localised states (oxide vacancies) in isolation layer. The capacitor connected in normal mode represents MIS structure polarized in reveres direction when the applied voltage higher potential barrier between semiconductor - MnO2 cathode and isolation of Ta2O5. The transport of charge carriers via isolation layer is determined by Poole-Frenkel mechanisms and tunnelling. Poole-Frenkel mechanism of charge transport is dominant in low intensity of electric field. Tunnelling determines current at higher electric field intensity. During low intensity of electric field ohmic component is also presented which is determined by volume of resistance of impurities in isolation layer due to donor states of oxygen vacancies. Based on the modelling of measured VA characteristics is possible to estimate determine dielectric thickness of Ta2O5 and determine share of Poole-Frenkelov and tunnel current and charge transportation. The thesis is described charge transport and charge concentration on tantalum capacitor in low frequency area and analysis of capacitor behaviour at frequency band. The first impulse for the thesis was an effort to create equivalent circuit diagram of tantalum capacitor in respect of its physical and electrical behaviour. There is an opportunity to study and determine electric charge transport and its accumulation based on the equivalent circuit diagram structure. There is also a chance to define and trace potential barriers and charge distribution in the capacitor structure based on an measurement and carried out experiments. This methodology and analysis consists of electrical characteristic determination to create physical model of the capacitor describing it function, properties and behaviour.
86

Mateřská škola / Kindergarten

Frieb, Vilém January 2022 (has links)
The aim of this master project is to design a nearly zero-energy building of kindergarten. The kindergarten is designed as one storey building with capacity of 40 children split into two playrooms. Playrooms are separated and each of them has own sanitary facilities and locker room. Playrooms have large windows with external blinds on the south to provide solar gains. There is horizontal sun breaker above the windows which prevent overheating in summer. Load bearing walls are made of sand lime blocks. Walls are insulated with mineral wool board. Roof ceiling is made of prestressed concrete slabs. The building has a flat extensive green roof. The second task of the project includes design of lighting, rainwater harvesting, HVAC, source of heat and photovoltaic system. The third part is theoretical and includes searching for an ideal source of energy for the building. There are two types of heating compared such as gas boiler and a groundwater heating pump. The main software used for the project is Revit.
87

Kamna v konceptu moderního vytápění / The stove in the concept of modern heating

Koutecký, Jan January 2012 (has links)
Thesis deals with stoves, considering them as the main source of heating. The theoretical part is focused on practical and theoretical stove designing and burnnig proces. The designing addresses three of the countless variations on the koncept of modern stove heating. Each variant is unique in its technical and design way of solution. Experiment affects the properties hypokaust stove.
88

Fotovoltaické dobíjecí regulátory v ostrovních systémech / Solar charge controllers for off-grid systems

KRČKA, Pavel January 2013 (has links)
This diploma thesis deals with photovoltaic rechargable regulators used in isolated, or off-grid photovoltaic systems. First, basic types of off-grid installations, including their functions and applications in practice are described. Then, possibilities of electric energy accumulation in photovoltaic systems are mentioned, considering actual, accesible technologies. Matters of electric energy accumulation in leaden accumulators are examined in detail. Main part of the diploma thesis is about electronic designs of photovoltaic, also called solar, rechargable regulators. These are the main connecting part between photovoltaic panels, accumulator, but also often connected charge, which is appliance. Individual electronic regulators concepts are described narrowly, then compared and evaluated in thesis´ conclusion.
89

Využití znalostních systémů a bází pro výběr a hodnocení domovních elektroinstalací / Utilization of Knowledge Systems and Bases for Selection and Evaluation of Domestic Electrical Installations.

Haluza, Miroslav January 2017 (has links)
My doctoral thesis deals with use of the sophisticated methods for the selection of technical and economic solution of electrical wiring. This solution is based not only on a price but also on many other criteria such as a comfort, service, durability etc. The focus of the work is a treatise on wiring systems from a global perspective, where it is impossible to use a conventional approach for objective evaluation and selection of the appropriate electrical wiring system (because of the complexity of such systems and their interdependencies). In the four chapter are given information of an energy consumption (the total consumption and household consumption). In this chapter is given also a consumption prediction – especially for households. Following is an overview of possible measures for reducing electricity consumption in households. In the next part of this thesis are solved the knowledge, respectively expert systems for use in an electrical engineering – especially for a suitable tool for the selection and evaluation of households wiring electrical system. The result of this work provides a possible solution for a selection of wiring electrical system for households (focusing on the intelligent wiring) – from a technical and economic point of view and with using an innovative approach. The main contribution of this work is a proposal of the main part of the knowledge base. This base could be as a basis for knowledge, respectively for an evaluating technical and economical solution of an electrical wiring system – the expert system includes also a feedback function of an effectiveness solution, use value, price etc., which would also serve as a knowledge base.
90

Začleňování fotovoltaických elektráren do elektrizační soustavy / Integration of Photovoltaic Power Plants in the Electricity System

Michl, Pavel January 2010 (has links)
The thesis discuses an integration of photovoltaic power stations to electric network. The first part describes connecting conditions of small sources to distribution system, including administrative requirements, feasibility study, and requirements to the energy meters, measuring, control devices, switching devices and protection. The second part is aimed to describe problems of the photovoltaic system. Solar radiation generating and reducing of its intensity incident upon the earth surface are described in this part. The quantum of produced electric power depends on climatic conditions in the fixed area, seasons, etc. This work also discusses the types of photovoltaic cells and their actual efficiency. Inverters are further important components of the photovoltaic system. The parameters of the inverters have a great influence on the total actual efficiency of the photovoltaic system. Different methods of the photovoltaic panels’ connection with the inverters and their advantages and disadvantages are also mentioned. The supporting structure of the photovoltaic panels and eventually transformer are further important components of photovoltaic system. The work also analyze the methods of connection of the photovoltaic power station to distributive low voltage and medium voltage network, electric energy accumulation and possibilities of the sale of produced electric energy. The large number of the connected photovoltaic power stations has negative influences to electric network. The third part contains the design of a photovoltaic power plant with a capacity of 516,24 kWp on the scoped area in southern Bohemia. The project documentation for the location where the power plant is designed is also made. It contains the design of photovoltaic panels, the design of the inverters to get an optimal power load. This part also contains a calculation of the photovoltaic system losses and the design of transformer and the cable junction calculation of the distributive system. The feasibility study of the power plant connected to distributive system is also conducted. Its delivery rate will be connected to the distribution point Řípov (110/22 kV). The calculation results show us that this photovoltaic power plant can be linked to the distribution system. The final part of this paper contains an economic estimate of the photovoltaic power plant operating and the calculation of the return. An Economic return is influenced by the wide range of values that affect the total return rate. The calculation of an operating economy is made for several variants. The return rate in refer to contemporary redemption price for 2010 with no consideration for a bank loan is 7 years. If we consider the bank loan it would be 12 years. The penetrative reduction of the redemption price is expected for 2011. Calculation works with the decline of 30 %. It would extend the rate of return to 11 years without a bank loan or to 22 years with the bank loan. The bank loan is considered to cover 80 % of the investment.

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