Three semi-permanent cloud bands exist in the Southern Hemisphere extending southeastward from the equator, through the tropics, and into the subtropics. The most prominent of these features occurs in the South Pacific and is referred to as the South Pacific Convergence Zone (SPCZ). Similar convergence zones, with less intensity, exist in the South Atlantic (SACZ) and Indian (SICZ) oceans. We attempt to explain the physical mechanisms that promote the diagonal orientation of the SPCZ and the processes that determine the timescales of its variability. It is argued that the slowly varying sea surface temperature patterns produce upper tropospheric wind fields that vary substantially in longitude. Regions where 200 hPa zonal winds decrease with longitude (i.e., negative zonal stretching deformation, or dU/dx<0) reduce the group speed of the eastward propagating synoptic (3-6 day period) Rossby waves and locally increase the wave energy density. Such a region of wave accumulation occurs in the vicinity of the SPCZ, thus providing a physical basis for the diagonal orientation and earlier observations that the zone acts as a "graveyard" of propagating synoptic disturbances. In essence, dU/dx=0 demarks the boundary of the graveyard while regions where dU/dx<0 denote the graveyard itself. Composites of the life cycles of synoptic waves confirm this hypothesis. From the graveyard hypothesis comes a more general theory accounting for the SPCZ's spatial orientation and its longer term variability influenced by the El Niño-Southern Oscillation (ENSO), or alternatively, the changing background SST associated with different phases of ENSO.

The master thesis will concern design of hybrid photovoltaic system for a family house with accumulation of electric energy. Three alternatives of power consumption will be made. For each alternative multiple simulations will be carried out with different amount of photovoltaic panels and batteries. The most appropriate alternative and size of photovoltaic system will be chosen based on those simulations. Finally the choice of alternative will be described.

This work is a numerical and analytical study of wave motion through dynamic materials (DM). This work focuses on showing several results that greatly extend the applicability of the checkerboard focusing effect. First, it is shown that it is possible to simultaneously focus dilatation and shear waves propagating through a linear elastic checkerboard structure. Next, it is shown that the focusing effect found for the original €œperfect€� checkerboard extends to the case of the checkerboard with smooth transitions between materials, this is termed a functionally graded (FG) checkerboard. With the additional assumption of a linear transition region, it is shown that there is a region of existence for limit cycles that takes the shape of a parallelogram in (m,n)-space. Similar to the perfect case, this is termed a €œplateau€� region. This shows that the robustness of the characteristic focusing effect is preserved even when the interfaces between materials are relaxed. Lastly, by using finite volume methods with limiting and adaptive mesh refinement, it is shown that energy accumulation is present for the functionally graded checkerboard as well as for the checkerboard with non-matching wave impedances. The main contribution of this work was to show that the characteristic focusing effect is highly robust and exists even under much more general assumptions than originally made. Furthermore, it provides a tool to assist future material engineers in constructing such structures. To this effect, exact bounds are given regarding how much the original perfect checkerboard structure can be spoiled before losing the expected characteristic focusing behavior.

This diploma thesis deals with the issue of heat pumps as devices using low-potential heat of the surrounding environment for heating of buildings. In the theoretical part of the thesis there are described various types of these devices, the sources of low-potential heat and the possibilities of heat energy accumulation. The practical part of the thesis is focused on processing and evaluation of operational data of air/water heat pump used for heating of family house and assessment of importance of accumulation tank in heating system. Part of the thesis is also a proposal of optimization of heat pump control.

This thesis focuses on the question whether it is economically viable to operate a system for household electricity production and if so, what are the necessary conditions to do so. In the text of this thesis a brief summary of environmental protection and sustainable development is presented, followed by the description and current state of technologies needed to construct systems for electricity production in the scale of family houses with focus on photovoltaic systems, and a description of the current legislation and administrative barriers related to this subject. Economic view (costs and return of investment) is examined in relation to multiple conditions, focus of this examination being on the geographical conditions, legislation and administrative conditions, state subsidies, electricity production and consumption profiles in the household and electricity price development scenarios. Technologies for household electricity production are therefore put into the context relevant to the citizens of the Czech Republic. The results of this work show, that the systems for photovoltaic electricity production in family houses in the conditions of the Czech Republic are economically viable with the premise that the surpluses of electricity produced are effectively consumed, for example for water...

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The objective of the first part of master’s thesis is mapping the potential of various types of renewable sources in Europe and Czech Republic, especially solar energy, wind energy, water energy and biomass. There are described principals and ways of energy generation from these sources, brief overview of current technologies, and also their advantages and limitations. An important part is electric supply continuity from renewable sources, there are large differences and the resulting to restrictions on construction and connecting the units to the power system. In this work there are mentioned some impacts on network and rates of change of supply, some sources are also evaluated in terms of maximum power, that can be connected to the power system in our country. The conclusion of the first part is dedicated to energy storage technologies, which are suitable and usable for renewable sources, there are described their principals, properties, status of development and types of aplications, in which these technologies are used. This chapter also focusses on the price level of each technology. The second part of the thesis deals with 1 MWp on-grid photovoltaic power plant design. This design includes also the redox flow batteries accumulation, the first variant calculates on 24-hour steady energy supply, the second optimalized variant calculates on daily energy supply. There are the accumulation system costs estimated and also the payback period for the both variants. Additionally there is also determined minimum penalization for cost-effective operation. The last part is dedicated to changes of impact on the local grid and changes of system impacts, after the accumulation system is installed.