Master's Thesis considers the idea of use of renewable energy sources for the generation of electricity. On the basis of reports on climate warming, the European Union took measures, which are mandatory for all Member States and aimed to increase the share of renewable energy in total energy production by 2010. Czech Republic has committed itself to produce 8% of energy from renewable energy sources, the government has created a system of subsidies to renewable energy sources and a system of redemption prices. These measures make energy very expensive. This work deals with the origin of these measures, which are reports on global warming. My work is also comparing predictions on the future status, as well as examining the advantages of investing in renewable energy sources and comparing the prices of subsidized energy with other types of energy.

<p>In this dissertation, we develop a novel methodology for characterizing and simulating nonstationary, full-field, stochastic turbulent wind fields. </p><p>In this new method, nonstationarity is characterized and modeled via temporal coherence, which is quantified in the discrete frequency domain by probability distributions of the differences in phase between adjacent Fourier components.</p><p>The empirical distributions of the phase differences can also be extracted from measured data, and the resulting temporal coherence parameters can quantify the occurrence of nonstationarity in empirical wind data.</p><p>This dissertation (1) implements temporal coherence in a desktop turbulence simulator, (2) calibrates empirical temporal coherence models for four wind datasets, and (3) quantifies the increase in lifetime wind turbine loads caused by temporal coherence.</p><p>The four wind datasets were intentionally chosen from locations around the world so that they had significantly different ambient atmospheric conditions.</p><p>The prevalence of temporal coherence and its relationship to other standard wind parameters was modeled through empirical joint distributions (EJDs), which involved fitting marginal distributions and calculating correlations.</p><p>EJDs have the added benefit of being able to generate samples of wind parameters that reflect the characteristics of a particular site.</p><p>Lastly, to characterize the effect of temporal coherence on design loads, we created four models in the open-source wind turbine simulator FAST based on the \windpact turbines, fit response surfaces to them, and used the response surfaces to calculate lifetime turbine responses to wind fields simulated with and without temporal coherence.</p><p>The training data for the response surfaces was generated from exhaustive FAST simulations that were run on the high-performance computing (HPC) facilities at the National Renewable Energy Laboratory.</p><p>This process was repeated for wind field parameters drawn from the empirical distributions and for wind samples drawn using the recommended procedure in the wind turbine design standard \iec.</p><p>The effect of temporal coherence was calculated as a percent increase in the lifetime load over the base value with no temporal coherence.</p> / Dissertation

abstract: An ongoing effort in the photovoltaic (PV) industry is to reduce the major manufacturing cost components of solar cells, the great majority of which are based on crystalline silicon (c-Si). This includes the substitution of screenprinted silver (Ag) cell contacts with alternative copper (Cu)-based contacts, usually applied with plating. Plated Cu contact schemes have been under study for many years with only minor traction in industrial production. One of the more commonly-cited barriers to the adoption of Cu-based contacts for photovoltaics is long-term reliability, as Cu is a significant contaminant in c-Si, forming precipitates that degrade performance via degradation of diode character and reduction of minority carrier lifetime. Cu contamination from contacts might cause degradation during field deployment if Cu is able to ingress into c-Si. Furthermore, Cu contamination is also known to cause a form of light-induced degradation (LID) which further degrades carrier lifetime when cells are exposed to light. Prior literature on Cu-contact reliability tended to focus on accelerated testing at the cell and wafer level that may not be entirely replicative of real-world environmental stresses in PV modules. This thesis is aimed at advancing the understanding of Cu-contact reliability from the perspective of quasi-commercial modules under more realistic stresses. In this thesis, c-Si solar cells with Cu-plated contacts are fabricated, made into PV modules, and subjected to environmental stress in an attempt to induce hypothesized failure modes and understand any new vulnerabilities that Cu contacts might introduce. In particular, damp heat stress is applied to conventional, p-type c-Si modules and high efficiency, n-type c-Si heterojunction modules. I present evidence of Cu-induced diode degradation that also depends on PV module materials, as well as degradation unrelated to Cu, and in either case suggest engineering solutions to the observed degradation. In a forensic search for degradation mechanisms, I present novel evidence of Cu outdiffusion from contact layers and encapsulant-driven contact corrosion as potential key factors. Finally, outdoor exposures to light uncover peculiarities in Cu-plated samples, but do not point to especially serious vulnerabilities. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2020

This thesis aims to design a modern innovative caravan. The main innovation of the proposal is seen in the new interior of motorhome class B for 4 persons with regard to minimal functional proportions. Independenc of energy. The main idea of the whole work is new compact interior designed according to ergonomy of person and with regard to main individual needs of user during their travelling and exterior, which brings a new face into motorhomes.Imterior brings several compromise solutions and several ideas for small spaces like multifunctional furniture. Small compact design for big travelling.

abstract: Photocatalytic water splitting over suspended nanoparticles represents a potential solution for achieving CO2-neutral energy generation and storage. To design efficient photocatalysts, a fundamental understanding of the material’s structure, electronic properties, defects, and how these are controlled via synthesis is essential. Both bulk and nanoscale materials characterization, in addition to various performance metrics, can be combined to elucidate functionality at multiple length scales. In this work, two promising visible light harvesting systems are studied in detail: Pt-functionalized graphitic carbon nitrides (g-CNxHys) and TiO2-supported CeO2-x composites. Electron energy-loss spectroscopy (EELS) is used to sense variations in the local concentration of amine moieties (defects believed to facilitate interfacial charge transfer) at the surface of a g-CNxHy flake. Using an aloof-beam configuration, spatial resolution is maximized while minimizing damage thus providing nanoscale vibrational fingerprints similar to infrared absorption spectra. Structural disorder in g-CNxHys is further studied using transmission electron microscopy at low electron fluence rates. In-plane structural fluctuations revealed variations in the local azimuthal orientation of the heptazine building blocks, allowing planar domain sizes to be related to the average polymer chain length. Furthermore, competing factors regulating photocatalytic performance in a series of Pt/g-CNxHys is elucidated. Increased polymer condensation in the g-CNxHy support enhances the rate of charge transfer to reactants owing to higher electronic mobility. However, active site densities are over 3x lower on the most condensed g-CNxHy which ultimately limits its H2 evolution rate (HER). Based on these findings, strategies to improve the cocatalyst configuration on intrinsically active supports are given. In TiO2/CeO2-x photocatalysts, the effect of the support particle size on the bulk/nanoscale properties and photocatalytic performance is investigated. Small anatase supports facilitate highly dispersed CeO2-x species, leading to increased visible light absorption and HERs resulting from a higher density of mixed metal oxide (MMO) interfaces with Ce3+ species. Using monochromated EELS, bandgap states associated with MMO interfaces are detected, revealing electronic transitions from 0.5 eV up to the bulk bandgap onset of anatase. Overall, the electron microscopy/spectroscopy techniques developed and applied herein sheds light onto the relevant defects and limiting processes operating within these photocatalyst systems thus suggesting rational design strategies. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2019

abstract: This dissertation develops advanced controls for distributed energy systems and evaluates performance on technical and economic benefits. Microgrids and thermal systems are of primary focus with applications shown for residential, commercial, and military applications that have differing equipment, rate structures, and objectives. Controls development for residential energy heating and cooling systems implement adaptive precooling strategies and thermal energy storage, with comparisons made of each approach separately and then together with precooling and thermal energy storage. Case studies show on-peak demand and annual energy related expenses can be reduced by up to 75.6% and 23.5%, respectively, for a Building America B10 Benchmark home in Phoenix Arizona, Los Angeles California, and Kona Hawaii. Microgrids for commercial applications follow after with increased complexity. Three control methods are developed and compared including a baseline logic-based control, model predictive control, and model predictive control with ancillary service control algorithms. Case studies show that a microgrid consisting of 326 kW solar PV, 634 kW/ 634 kWh battery, and a 350 kW diesel generator can reduce on-peak demand and annual energy related expenses by 82.2% and 44.1%, respectively. Findings also show that employing a model predictive control algorithm with ancillary services can reduce operating expenses by 23.5% when compared to a logic-based algorithm. Microgrid evaluation continues with an investigation of off-grid operation and resilience for military applications. A statistical model is developed to evaluate the survivability (i.e. probability to meet critical load during an islanding event) to serve critical load out to 7 days of grid outage. Case studies compare the resilience of a generator-only microgrid consisting of 5,250 kW in generators and hybrid microgrid consisting of 2,250 kW generators, 3,450 kW / 13,800 kWh storage, and 16,479 kW solar photovoltaics. Findings show that the hybrid microgrid improves survivability by 10.0% and decreases fuel consumption by 47.8% over a 168-hour islanding event when compared to a generator-only microgrid under nominal conditions. Findings in this dissertation can increase the adoption of reliable, low cost, and low carbon distributed energy systems by improving the operational capabilities and economic benefits to a variety of customers and utilities. / Dissertation/Thesis / Doctoral Dissertation Engineering 2019

This work is trying to establish and answer three questions about the concept of Intermarium: Which concepts of the Intermarium that were formed in the past, are still relevant in modern geopolitical circumstances? What political conditions force the country to become a potential participant of the Intermarium? What minimal number of countries is sufficient enough for membership in the Intermarium to provide its effective activity in the political arena? The questions are answered through the implementation of a comparative method. The chosen method is applied to the selected states of the specified region on the basis of two selected cases that correspond to analogical situations in the history of these countries and resulted in the birth of the concept of the Intermarium as one of the possibilities for solving the political crisis in the historical period, which is chosen for the case. This work with case studies will allow the researcher to obtain a high level of conceptual validity as well as to evaluate the indicators that fully explain the theoretical concepts. Since certain internal and external factors such as political system, political culture, state power, economic independence, defensive capabilities, cultural and historical mentality, membership in international organizations are...

The purpose of the thesis is to determine the potential of lessening the high energy cost in the hospitality industry so that the industry could stay alive after a three decades of civil war in Sri Lanka. The hospitality industry is a significant contributor to the country’s economic growth. Tourism industry has much hope of recovering in the year 2010. Improved tourism would also benefit larger part of Sri Lankan population as they are directly and indirectly employed to serve the tourism industry. Sri Lanka has a high electricity production cost as it depends heavily on the imported fossil fuel. Survival of hospitality industry would depend on the manner in which the energy cost - the second highest overhead in hotels is managed. If the industry survives, Sri Lanka would receive more foreign exchange and thereby improve country’s foreign currency reserve which could contribute to high growth rate. As electricity production is mainly depending on thermal, the volatility of world crude oil prices is directly affecting the country’s electricity prices. However, low dependence on the grid would help the hospitality industry to mitigate the energy cost. As the electricity and diesel costs -the highest and the next - are considerable portions in energy cost in hospitality industry, the study aims to discuss the possible ways of mitigating such costs. Measurements done by the presenters found that the usage of electricity for air conditioning system does constitute most of the electricity consumption for a hotel whilst most of the diesel consumption is for thermal applications. If Air Conditioning (AC) can be operated without electricity and thermal applications could be operated using abundantly available alternative energy sources then the overall energy costs of hospitality industry could be reduced thereby making higher profits. This would ensure industry survives and country gets more foreign exchange.  Study and calculations done by the presenters proved that operating of generators only for electricity production is not viable, due to high fossil fuel cost, however if its high exhaust temperature which is wasted otherwise, could be utilized for operation of absorption chillier then the dependence of grid electricity for air conditioning could be minimized. Further studies also revealed that if water cooled generator is used for such purpose instead of air cooled, and then the hot water requirement of hotel also could be fulfilled, thus mitigating the dependence of fossil fuel which is used otherwise for hot water production. Study also revealed that if thermal energy could be fed with biomass- Sri Lanka being a tropical country is blessed with abundantly available biomass - then the dependency on the fossil fuel for thermal applications could be avoided. This would not only mitigate the second highest energy cost for hotels but also create less carbon foot print, more environmental friendly and produce less noxious exhaust gases thereby creating an advertisement to attract tourists who longing to support green hotels

A large-scale transition to renewable energy sources will become increasingly appealing as the issues of federal regulation, climate change, and decreased fossil fuel energy return on energy investment become more prevalent. Although renewable resources remain a small portion of the nation’s and Utah’s energy portfolio mix, current power purchase agreements indicate an impending boom. Cooperative Extension should play an integral role in the transition to renewable resources on the national, state, and local levels. The purpose of Extension is to provide objective, research-based, and credible information to improve local communities. There is a great opportunity for Extension agents to be trusted experts in educating and assisting farmers, ranchers, and homeowners in transitioning to renewable energy systems. This thesis identified the benefits, barriers, and opportunities for renewable energy outreach in Extension. Data were collected through a nationwide online survey and focus group interviews, in addition to a Utah-based online survey. The nationwide survey and interviews revealed a need and demand for increased renewable energy programming in Extension. This need became further evident after a nationwide inventory discovered that only twenty-two of fifty states have distinct renewable energy departments, programs, or discipline areas. A Utah-based needs assessment revealed that fifty-nine percent of Utah State University (USU) Extension employees agreed that there was a need for a statewide renewable energy specialist. Additionally, more than fifty-five percent of employees agreed that there was an internal and public demand for USU Extension to provide and receive renewable energy information, programs, education, and outreach. The Utah-based survey also revealed differing perceptions of the environmental harmfulness of common energy sources. Different attitudes toward conventional and renewable energy sources demonstrated the need for unbiased, properly messaged delivery of desired renewable energy programs.

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