|
Elektromobily, plug-in hybridy a jejich užívání v běžném provozu
Benda, Marek
The subject of the bachelor thesis is a focus on the automotive industry with a specification for electric cars and plug-in hybrids. The introductory part of the work characterizes the basic division of vehicles with electric drive, describes and divides the propulsion systems, and clarifies the use and construction of individual components of the vehicle. It follows the current state of affairs, which describes the use and maintenance of vehicles with a high-voltage system, their driving characteristics, charging, emissions, maintenance of the battery and electrical unit. The work is also focused on all costs associated with the acquisition of such a car. The final part of the bachelor thesis consists of questionnaire survey on electromobility. This survey communicates and confronts the familiarity of vehicle users with different drives.
|
|
Trends in renewable sources and in modern energy
Kotas, Tomáš ; Preisler, Lukáš (referee) ; Kudela, Libor (advisor)
The bachelor thesis deals with the issue of renewable energy sources. Renewable energy sources are categorized and extensively described, including the principles of their functions and basic parameters. The thesis further focuses on the development of the position of renewable energy sources over the years compared to non-renewable energy sources worldwide and in the Czech Republic. This development is monitored in terms of both electricity and heat. Statistics indicate that the share of renewable energy sources in both forms of energy is increasing. The thesis also analyzes the origin and course of discussions related to this issue, including climate change and international cooperation. Possible predictions and specific scenarios related to the energy vision are provided for both the Czech Republic and on a global scale within the thesis. All scenarios agree on the same future trend – an increasing share of renewable energy sources at the expense of non-renewable sources. In conclusion, the thesis addresses current trends in technologies in modern energy, with the most significant technological progress in recent years observed in the fields of electromobility, hydrogen, and CCUS. The final chapter discusses methods of energy storage.
|
|
Hydrogen pressure reduction before injection into the power unit
Švestka, Jiří ; Zeizinger, Lukáš (referee) ; Štětina, Josef (advisor)
This bachelor thesis's central argument revolves around the depressurisation of hydrogen and the pressure regulator required to do so. It explores the journey of hydrogen from its production through distribution to the ways of multiple applications. Specific emphasis is placed on the characteristic properties of hydrogen that need to be taken into account during the design of the reduction valve itself. In this thesis, the design of a high-pressure pressure regulator optimized for piece production is presented, together with an analysis of the dynamics of hydrogen as it passes through the valve.
|
|
Assessment of the change in the fuel base of the Počerady combi cycle power plant
Krakovský, Matej ; Lisý, Martin (referee) ; Milčák, Pavel (advisor)
Combined cycle is a thermal cycle, that is used in thermal power plants mainly because of its high efficiency – combination of a gas turbine and a steam turbine, where we use the waste heat from the gas turbine in the steam cycle. The aim of this thesis was the determination of parameters in case of fuel exchange, that means mixing hydrogen into natural gas. Calculation model was related to the specific power plant – combined cycle in Počerady. The thesis is completed with the theoretical description of fuels and the description of individual thermal cycles. One chapter is also dedicated to details of the powerplant in Počerady.
|
|
Creation of a model of the hydrogen filling station network in the Czech Republic
Kotrla, Tomáš ; Bilík, Martin (referee) ; Maxera, Pavel (advisor)
The diploma thesis deals with the issue of hydrogen vehicles, as one of the alternatives to classic vehicles with internal combustion engines. The work first researches the functioning of hydrogen technology, its infrastructure and influences of the third parties, with the aim of taking a closer look of its future development. This mainly depends on the research of the future number of hydrogen vehicles. Sufficient capacity of fuel must be ensured for them. That’s why a sufficient amount of hydrogen must be produced, which will be distributed to filling stations. There also needs to be enough of them. The main goal of the work is to design a distribution network model that will be able to ensure these requirements. The results of the work are verified using simulation modeling to verify the functionality of the proposed distribution network model.
|
|
Hydrogen and safety in transport
Rusek, Rostislav ; Böhm, Michael (referee) ; Poulíček, Matěj (advisor)
This bachelor thesis identifies the risks associated with the leakage, storage and handling of hydrogen as a promising low-emission fuel of the future. It starts by giving the basic characteristics of hydrogen, or its storage and transport methods. It then analyses existing safety measures, describes hydrogen transport and technological innovations from an economic and environmental perspective. The final section compares hydrogen with alternative fuels, namely compressed natural gas and liquefied petroleum gas. This thesis is based on a search of the relevant literature, summarises current knowledge and highlights the need for further research to ensure a secure future for hydrogen as an alternative fuel in transport vehicles and infrastructure.
|
|
Residual life assessment of hydrogen adsorption vessel subjected to cyclic loading
Brančan, Peter ; Vincour, Dušan (referee) ; Létal, Tomáš (advisor)
There was a need to asses the residual life of a cyclically pressurized adsorber of PSA unit used for the separation of hydrogen gas from a feedstock mixture, of which designed lifetime according to outdated standart ČSN 69 0010-4.20 was exceeded. The maximum design life was determined according to more recent design codes by the methodology of fatigue curves and comparison of results of outdated standard and 3 newer standards: EN 13445-3 - clause 17 and clause 18, and ASME BPVC Section VIII Div.2 - Level 2 was made. Due to the exceeding of the design life results by all of the standards the alternative approach of Fitness for service method based on linear elastic fracture mechanics of crack growth with the assumption of the occurrence of non-detectable defect size was used. The crack growth parameters were adjusted according to the study of crack propagation in hydrogen environment and implemented into the calculation of API-579-1/ASME FFS-1 Fitness for Service standard. The results showed, that pressure vessel can be further operated if regular NDT inspections are made. Inspection intervals of critical positions were determined from these results with compliance to safety and, at the same time, the scope of inspections has been modified to reduce expenses of carrying them out.
|
|
Fuel cell model in PSCAD
Černý, František ; Ptáček, Michal (referee) ; Radil, Lukáš (advisor)
The bachelor thesis deals with the creation of a model of different fuel cells. It is intended to broaden the view of currently available fuel cells their principle function and to describe their advantages and disadvantages. It also describes the basic equation of the magnitude of the voltage generated at the electrodes of the cell and the types of voltage losses that occur during its operation. Creating a custom fuel cell model and comparing simulations of this model with real cells and, with datasheets of available fuel cells.
|
|
Conceptual design of hydrogen storage
Svoboda, Filip ; Lisý, Martin (referee) ; Milčák, Pavel (advisor)
The main objective of this thesis is to propose the storage of surplus electricity from a photovoltaic power plant in the form of green hydrogen. For the design of hydrogen accumulation it is necessary to determine the balance of production and consumption of electricity from PV power plant, then design a specific type of electrolyzer, type of hydrogen storage and use of hydrogen. The final step is the creation of a technological scheme of a specific solution of power to gas to power technology. The expansion of this type of hydrogen economy can lead to a large increase in the use of low carbon sources and help in the path to carbon neutrality.
|
|
Computational prediction of operating parameters of cogeneration units
Kašpar, Jakub ; Daxner, Ján (referee) ; Jegla, Zdeněk (advisor)
The focus of this work is on gas-fired combined heat and power (CHP) units with internal combustion engine. The aim is to present and analyse a prediction model with subsequent modification and experimental validation. This is preceded by a proper theoretical introduction to CHP units. First, the role of CHP in the transformation of the contemporary energy sector, which is under increasing demands, is outlined. Next, the types of CHP units are briefly introduced, including their advantages. This is followed by a detailed description of their design together with the factors influencing their operating parameters. For the understanding of the subject, emphasis is placed on the description of analytical relations in the field of thermomechanics and physical chemistry. Furthermore, the modelling of CHP is approached based on knowledge gained during the study and work experience in the field of CHP units. The final adjusted predictive model shows deviations of up to 12 % with respect to the nominal parameters. When validated with experimental data, it shows a deviation of up to 31,1 %. In general, the model is not suitable for accurate prediction of operating parameters. However, it has been successfully validated in determining the trend of the dependence of the operating parameters on the hydrogen concentration in the fuel.
|