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[en] Variable renewable energy sources (VRE) for electricity generation, such as wind and solar power, are subject to inherent output fluctuations. This variability has significant impacts on power system and electricity markets if VRE are deployed at large scale. While on global average, wind and solar power currently supply only a minor share of electricity, they are expected to play a much larger role in the future - such that variability will become a major issue (which it already is in some regions). This thesis contributes to the literature that assesses these impacts the ''system and market integration'' literature. This thesis aims at answering the question: What is the impact of wind and solar power variability on the economics of these technologies? It will be laid out that the impact can be expressed in (at least) three ways: as reduction of value, as increase of cost, or as decrease of optimal deployment. Translating between these perspectives is not trivial, as evidenced by the confusion around the concept of ''integration costs''. Hence, more specifically: How does variability impact the marginal economic value of these power sources, their optimal deployment, and their integration costs? This is the question that this thesis addresses. This study comprises six papers, of which two develop a valuation framework that accounts for the specific characteristics of the good electricity, and the specific properties of wind and solar power versus ''dispatchable'' power plants. Three articles then assess quantitative questions and estimate marginal value, optimal deployment, and integration costs. These estimates stem from a newly developed numerical power market model, EMMA, market data, and quantitative literature reviews. The final paper addresses market design. In short, the principal findings of this thesis are as follows. Electricity is a peculiar economic good, being at the same time perfectly homogenous and heterogeneous along three dimensions - time, space, and lead-time. Electricity's heterogeneity is rooted in its physics, notably the fact it cannot be stored. (Only) because of heterogeneity, the economics of wind and solar power are affected by their variability. The impact of variability, expressed in terms of marginal value, can be quite significant: for example, at 30% wind market share, electricity from wind power is worth 30-50% less than electricity from a constant source, as this study estimates. This value drop stems mainly from the fact that the capital embodied in thermal plants is utilized less in power systems with high VRE shares. Any welfare analysis of VRE needs to take electricity's heterogeneity into account. The impact of variability on VRE cannot only be expressed in terms of marginal value, but also in terms of costs, or in terms of optimal deployment. The mentioned value drop corresponds to an increase of costs by 30-50%, or a reduction of the optimal share by two thirds. These findings lead to seven policy conclusions: 1. Wind power will play a significant role (compared to today). 2. Wind power will play a limited role (compared to some political ambitions). 3. There are many effective options to integrate wind power into power systems, including transmission investments, flexibilizing thermal generators, and advancing wind turbine design. Electricity storage, in contrast, plays a limited role (however, it can play a larger role for integrating solar). 4. For these integration measures to materialize, it is important to get both prices and policies right. Prices need to reflect marginal costs, entry barriers should be tiered down, and policy must not shield agents from incentives. 5. VRE capacity should be brought to the system at a moderate pace. 6. VRE do not go well together with nuclear power or carbon capture and storage - these technologies are too capital intensive. 7. Large-scale VRE deployment is not only an efficiency issue, but has also distributional consequences. Re-distribution can be large and might an important policy driver.
[en] Until now, the development of the useful micro electromechanical systems has the problems because previous batteries (solar, chemical, etc) did not satisfy the requirements related to power supply. At this point of time, nuclear battery using isotope sources is rising the solution of this problem. Nuclear battery can provide superior out-put power and lifetime. So a new type of micro power source (nuclear battery) for micro electromechanical systems has been designed and analyzed. In this work, I designed the three parts, isotope source, conversion device, and shielding. I chose suitable sources, and designed semiconductor using the chosen isotope sources. Power is generated by radiation exciting electrons in the semiconductor depletion region. The efficiency of the nuclear battery depends upon the pn-junction. In this study the several conceptual nuclear batteries using radioactive materials are described with pn-junction. And for the safety, I designed the shielding to protect the environment by reducing the kinetic energy of beta particles
[en] Polarimetric Synthetic Aperture Radar Interferometry (Pol-InSAR) is an active radar remote sensing technique based on the coherent combination of both polarimetric and interferometric observables. The Pol-InSAR technique provided a step forward in quantitative forest parameter estimation. In the last decade, airborne SAR experiments evaluated the potential of Pol-InSAR techniques to estimate forest parameters (e.g., the forest height and biomass) with high accuracy over various local forest test sites. This dissertation addresses the actual status, potentials and limitations of Pol-InSAR inversion techniques for 3-D forest parameter estimations on a global scale using lower frequencies such as L- and P-band. The multi-baseline Pol-InSAR inversion technique is applied to optimize the performance with respect to the actual level of the vertical wave number and to mitigate the impact of temporal decorrelation on the Pol-InSAR forest parameter inversion. Temporal decorrelation is a critical issue for successful Pol-InSAR inversion in the case of repeat-pass Pol-InSAR data, as provided by conventional satellites or airborne SAR systems. Despite the limiting impact of temporal decorrelation in Pol-InSAR inversion, it remains a poorly understood factor in forest height inversion. Therefore, the main goal of this dissertation is to provide a quantitative estimation of the temporal decorrelation effects by using multi-baseline Pol-InSAR data. A new approach to quantify the different temporal decorrelation components is proposed and discussed. Temporal decorrelation coefficients are estimated for temporal baselines ranging from 10 minutes to 54 days and are converted to height inversion errors. In addition, the potential of Pol-InSAR forest parameter estimation techniques is addressed and projected onto future spaceborne system configurations and mission scenarios (Tandem-L and BIOMASS satellite missions at L- and P-band). The impact of the system parameters (e.g., bandwidth, NESZ, ambiguities) and the operation scenario (e.g., temporal decorrelation due to a repeat-pass orbit) is evaluated and discussed with respect to the retrieval of the forest parameters. The study is supported and validated by using repeat-pass Pol-InSAR data at L- and P-band acquired by DLR's E-SAR system over Remningstorp (BioSAR 2007, hemi-boreal forest), Krycklan (BioSAR 2008, boreal forest) and Traunstein (TempoSAR 2008 and 2009, temperate forest) test sites. The simulated spaceborne data sets generated during the BioSAR 2007 campaign are used to carry out the performance analysis.
[en] The infrared spectrum of water is possibly one of the most well studied and yet portions of it are still poorly understood. Recently, significant advances have been made in assigning water spectra using variational nuclear calculations. The major factor determining the accuracy of ro-vibrational spectra of water is the accuracy of the underlying Potential Energy Surface. Even the most accurate ab initio Potential Energy Surface does not reproduce the Born-Oppenheimer surface to sufficient accuracy for spectroscopic studies. Furthermore, effects beyond this model such as the adiabatic correction, the relativistic correction and the non-adiabatic correction have to be considered. This thesis includes a discussion on how the relativistic correction was calculated, for the water molecule, from first-order perturbation theory. The relativistic correction improved vibrational stretching motion while making the prediction of the bending modes far worse. For rotational motion the relativistic effect had an increasing effect with increasing Ka. A further alteration to the ab initio calculations is introduced by adjusting the barrier to linearity in the water potential. This alteration to the barrier was considered in order to compensate for the lack of convergence of quantum chemical calculations of the Born-Oppenheimer surface. This barrier attempts to represent the change in the potential from linear to equilibrium. We show the improvements this has on the calculated energy levels by comparison with the HITRAN database. This then led the way to the improved spectroscopic potential presented here in this thesis. This new spectroscopic potential reduces the overall standard deviation significantly for vibrational and rotational energy levels. (author)
[en] In recent years, there was an improvement in utilizing solar energy and using solar applications in Sudan.This improvement requires awareness of using this technology and collaboration among all people who have been involved in this process. In this study, an attempt is made to architecturally incorporate of solar applications with different buildings in Sudan. Mounting of solar applications within buildings in Sudan is not according to any architectural standards.That, therefor, led to losses of its appearance within buildings. Special emphasis on buildings in Khartoum has been made. Samples from different types of building have been chosen as a case study, and have been analyzed to indicate how these buildings accept this technology and to study the architectural value of this integration. In addition to that, conclusions and recommendations for buildings integrated solar applications have been made, together with some guidelines for further studies.The goal is to have the solar building.(Author)
[en] The main barriers for the deployment of renewable energy sources (RES) facilities in the Russian Federation are the lack of political, legislative and regulatory support, low prices for electricity and heat generated from fossil fuels, lack of information for decision makers (e.g. data from research projects) as well as the preference for centralized energy supply schemes. These barriers are contributing to an inadequate investment climate for the implementation of RES facilities. Nevertheless, in some regions of the Russian federation with a potential of RES and a comparatively low degree of economic centralization the situation is different. In the present thesis, the initial conditions for the development of RES potentials for the production of wind, solar and biomass energy in the Krasnodar region (southwestern region of the Russian Federation) are examined using a multi-criteria assessment methodology. For the assessment of the RES potentials at regional scale, the prosed multi-criteria methodology based on the geographic information systems (GIS) and has been complemented by the evaluation and analysis of primary and secondary data as well as economic calculations relevant related to economic feasibility of RES projects. The Krasnodar region has been chosen as model region for other regions in the Russian Federation, Eastern Europe and the former Soviet Union that have unexplored RES potentials but lack sufficient data for the assessment of RES potentials in GIS. An innovative element of the proposed multi-criteria methodology is the combined assessment of the maximum available factors relevant for the economically feasible exploration of RES potentials. These factors included the energy status with the specific features of the energy infrastructure, the energy policy relevant for RES along with the market and economic conditions of the region. The main objectives of the assessment of the RES potentials in the Krasnodar region were (1) to examine and present the energy status and the market conditions in GIS map as the essential conditions for an implementation of GIS facilities; (2) to calculate and present the available yield of wind, solar and biomass energy output through consideration of environmental and land-use restrictions reducing the theoretical resource potential, to the technologically and eventually the economically exploitable share of the initial resource potential; (3) to model energy scenarios and develop specific recommendations for and improved planning of future projects on RES in the study region. The assessment of the theoretical and technological wind energy potential utilized GIS models on extrapolation of wind speed, on suitability class (optimal locations for installation of RES facilities), on wind power density and wind energy estimation. For the assessment of the theoretic and technological solar energy potential, the kriging model, the suitability class model as well as the solar energy estimation model were applied in GIS. The assessment of the biomass energy potential utilized net primary productivity (NPP) and statistic data on organic wastes organic and animal manure using the GIS generic model. Optimal locations for the installation of biomass power plants were identified using network analysis tools in QGIS. The assessment of the technical wind energy potential in the Krasnodar region yielded an electricity production of 23 GWh year-1. Taking into account all the environmental and infrastructural restrictions as well as the current market conditions, the technical energy potential was subjected to reduction to an economically viable share of 0.8 GWh year-1. The total technical solar energy potential amounts to 24 GWh year-1. However, the economically viable share of the solar electricity is 4.5 GWh year-1 due to economic restrictions. The assessment of the biomass energy potential yielded an electricity production from biomass residues of 25 GWh year-1, which, however, was subjected to reduction to 4.7 GWh year-1 due to specific restrictions. The calculated unit (kWh) generation prices for hypothetical energy production facilities in both rural and urban areas of the Krasnodar region were Euros 0.15 (urban-utility scale) and Euros 0.20 (rural-utility scale) for wind electricity, Euros 0.16 (urban PV installations of up to 2 MW) and Euros 0.25 (rural PV installations of up to 1 kW) for solar electricity, and Euros 0.12 (rural-utility scale) and Euros 0.14 (urban-utility scale) for biomass electricity. Compared to the current mean unit generation prices for electricity from conventional energy sources of Euros 0.06 per kWh, the RES electricity prices are not competitive under the current regional and governmental energy policy. The recommendations provided in this thesis aim to highlight relevant support and measures to enable further development of RES potentials in the Krasnodar region. Thus, due to the application of an integrative multifactorial GIS-analysis it was possible to comprehensively estimate the RES potentials in the present work. Detailed and step-by-step analysis of constraints, the energy situation, and the market climate made an indepth feasibility assessment of potential RES projects in the study region. Thus, it was possible to answer the question why, despite the great potential of RES, there are no successful projects in the study region. As a result, reliable information about the RES potential in the region was provided, minimizing risks for investors and policy makers. For other regions, the proposed multi-criteria methodology provides a multi-purpose approach for a complex exploration of RES potentials and their exploitation under specific environmental and economic conditions.
[en] This study deals with the topic geothermal energy. Although geothermal energy is an important energy sector within the area of the renewable energies, the European policy downgraded this important, promising energy sector in 1999. Normally, geothermal energy cannot be regarded as a renewable energy source because the heat content of the Earth, the gravitational heat, the source heat, frictional heat and the decay of radioactive isotopes in the further process of geologic history will eventually be exhausted. However, we are referring here to many millions of years. At the present time, geothermal energy can thus be regarded as an inexhaustible renewable energy source. This work is focused on the geothermal situation in Austria. For many people, the term 'geothermal energy' is associated with countries such as Iceland, Italy (Larderello) and New Zealand. However, in Austria there are also innovative projects in the geothermal energy sector that only very few people know about. Some of these trend-setting projects are presented here. Regarding the total situation in Austria, the geothermal potential is described specifically for the Calcareous Alpine nappe and the Vienna Basin. Furthermore, the first results concerning successful injection in Upper Austria and up to now unconsidered locations for geothermal energy plants are presented. This work attempts to present the attractiveness of geothermal energy projects to the public, thus emphasizing the importance of discussing it again on the political level. (author)