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[en] Inertialization of residues is a key task of incinerators. Residues of conventional incineration processes may contain high levels of inorganic or organic pollutants and must be treated prior to recycling. the most effective process is thermal treatment above the melting point. This will destroy organic pollutants like dioxins/furans and pathogenic compounds, while the heavy metals will be partly volatilized. The glassy slag obtained as end product is low in heavy metals and more or less resistant to leaching. The The author describes a method for calculating activity coefficients of volatile components of diluted, liquid multicomponent systems. With these data, the data base for thermodynamic description of fluid mixtures was updated, and a set of characteristic data was established for describing transport in an inflatable module. Once the activity coefficients of interesting constituents of the slag are known along with the transport conditions in the volatilization process, it is possible to optimize the thermal treatment of critical ashes and dusts with a view to energy consumption and process control. In two different exemplary process concepts, the energy consumption for residue treatment is estimated. The processes proposed are compared with published process proposals, and their energy consumption is assessed in a comoparative study
[de]Eine der wesentlichen Aufgaben der Abfallverbrennung ist die Inertisierung des Abfalls. Da die festen Rueckstaende aus klassischen Verbrennungsverfahren hohe Gehalte an anorganischen und organischen Schadstoffen aufweisen, koennen sie nicht ohne Vorbehandlung weiterverwertet werden. Das im Hinblick auf die Inertisierung wirkungsvollste Verfahren ist die thermische Behandlung der Verbrennungsrueckstaende oberhalb des Schmelzpunktes. Hierbei werden die organischen Schadstoffe wie Dioxine/Furane oder pathogene Bestandteile zerstoert und die Schwermetalle teilweise verfluechtigt. Die so erzeugte glasfoermige Schlacke ist schwermetallarm und weitgehend laugungsresistent. Im Rahmen dieser Arbeit wurde eine Methode zur Bestimmung der Aktivitaetskoeffizienten von fluechtigen Komponenten aus verduennten, fluessigen Mehrkomponentensystemen entwickelt. Durch die mit dem Verfahren ermittelten Stoffdaten wird die Datenbasis zur thermodynamischen Beschreibung entsprechender Stoffgemische erweitert. Darueber hinaus wurde unter Zugrundelegung eigener Experimente und von Messungen aus der Literatur ein Kennzahlenansatz zur Beschreibung des Stofftransports in einem Aufblasmodul abgeleitet. Mit der Kenntnis der Aktivitaetskoeffizienten interessierender Konstituenten der Schlacken und der Stofftransportbedingungen im Verfluechtigungsprozess ist es moeglich, die thermische Behandlung kritischer Aschen und Staeube optimiert in Bezug auf den Energieeinsatz und die Prozessfuehrung zu gestalten. Beispielhaft wird fuer zwei unterschiedliche Prozesskonzepte der Energiebedarf fuer die Reststoffbehandlung abgeschaetzt. Die vorgeschlagenen Prozesse werden mit Verfahrensvorschlaegen aus der Literatur verglichen und im Hinblick auf den Energiebedarf bewertet. (orig.)
[en] This study addresses attitudes toward nuclear power in an international comparative setting for two distinct scenarios: In a period without an issue-related exogenous shock and in the wake of nuclear accidents. As it cannot be taken for granted that citizens attach increased importance to issues of energy policy, the theoretical discussion deals with various implications of relative issue saliences with a focus on varying politicization levels. The empirical analyses for periods without external events reveals profound context-specific patterns when it comes to the association between predispositions and the evaluation of nuclear power. Theoretical mechanisms that are often generally assumed in the literature are mainly found in economically advanced countries. Moreover, using the Fukushima accident as an example for a scenario with an exogenous shock, the analysis highlights that attitudinal and behavioral reactions have to be conceived of as a complex interaction of elite cues, individual predispositions and long-term dynamics in issue salience. Based on three case studies, the investigation suggests that an increase in issue salience is only present in the immediate aftermath of the Fukushima disaster, if at all. As context-specific politicization is relevant for a wide array of political issues - especially for less important topics - the study provides substantial and methodological implications beyond just the scope of the nuclear power issue.
[en] The liberalisation of electricity markets and the increase of renewable energy generation actually causes dramatic changes for the whole European power industry. The transmission system operators in particular have to meet the challenge to ensure a stable and reliable system operation in the future. Significant changes in power generation will require a substantial extension to current inadequate original transmission grids to handle increased wide area power flows. This is the only way to avoid overloading the grid and to reduce the herefrom resulting limitations for the Pan-European cross-border trade of electricity. This work describes in detail the development of a Pan-European integrated grid and an electricity market simulation tool. For this purpose an overview about the today's structure of the European electricity industry is given initially. Afterwards the configuration of the transmission grid, the used equipment and different methods for the load flow and short circuit calculation are explained. Furthermore models for the calculation of local loads and the power plant dispatch are presented in the following chapters. Following on from this a detailed model of the European electricity industry is developed and the main functions are described by means of some exemplary simulations. The simulation tool developed in this work enables the user to calculate realistic power plant schedules and the consequent resulting physical effects on the European transmission grid. It combines a time series based simulation of the electricity market with a detailed model of the transmission grid. The highly detailing of the model offers the feasibility to execute a complete AC load flow calculation using the Newton Raphson algorithm.Therefore it is possible to identify the active as well as the reactive power flows in the grid. The results of the power flow calculation are the basis for further investigations (e. g. the short circuit calculation) and to decide on reasonable grid extension tasks. An essential part of the simulation of the electricity market is also the consideration of the international electricity trade. This leads to a very complex optimisation problem, which is solved by an evolutionary strategy in this work. Because the whole model is based on publicly available data, it is a platform for the continuing scientific research at the University of Hanover, in which new aspects, which are not part of this work (e. g. stability analysis or the dynamic behaviour of the grid), will be investigated.
[en] In recent times, environmental, energy and climate policies have gained tremendously in importance. Not least, this is due to the latest research findings related to climate change and the resulting growing environmental awareness among people. However, policy approaches to combat environmental pollution and climate change differ both in their intention and in their economic impacts. For instance, command-and-control instruments such as performance or technology standards have different implications than market-based mechanisms such as permit trading of greenhouse gas emissions. Furthermore, sectoral and regional characteristics play an important role when implementing and assessing policy measures. This applies both to the attainability of the targets and to the available instruments. The present doctoral thesis addresses this point and analyzes in several essays different policy instruments and their economic effects from global, regional and sectoral perspectives. In this respect, it deals with various, often very heterogeneous question: How are specific policy types implemented in different countries? What is the CO2 abatement potential in specific regions and sectors? What policy measures can be plausibly used to exploit this potential? How can technological developments and technology-directed policy interventions contribute to improve energy efficiency? Does the promotion of certain energy sources necessarily create positive production and employment effects? To answer these and further questions, different economic methods are applied that accommodate the particular problem, where special emphasis is put on computable general equilibrium modeling. The aim of this work is to contribute to the academic and political debate on measures to combat environmental and climate problems.
[en] In times of increasing global uncertainties, science takes a central position for policy decisions. According to Peter M. Haas, epistemic communities are able to influence the cooperative behavior of states through their consensual knowledge. This book critically examines this statement. As the case of the Framework Convention on Climate Change shows, the World Climate Council (IPCC) was not in a position to enforce its solution options in the intergovernmental negotiations, as these affected the individual convictions of the decision-makers. While Angela Merkel advocated an agreement, the US government under George W. Bush denied the existence of climate change. Decision-makers and their individual convictions must therefore have a greater significance in international politics.
[de]In Zeiten zunehmender globaler Unsicherheiten nimmt die Wissenschaft fuer die Entscheidungen der Politik eine zentrale Stellung ein. Epistemic communities sind nach Peter M. Haas durch ihr konsensuales Wissen in der Lage, das Kooperationsverhalten von Staaten zu beeinflussen. Das vorliegende Buch prueft diese Aussage kritisch. Wie der Fall der Klimarahmenkonvention zeigt, war der Weltklimarat (IPCC) nicht in der Lage, seine Loesungsoptionen in den zwischenstaatlichen Verhandlungen durchzusetzen, da diesen die individuellen Ueberzeugungen der Entscheidungstraeger entgegenstanden. Waehrend Angela Merkel ein Abkommen befuerwortete, bestritt die US-Regierung unter George W. Bush die Existenz des Klimawandels. Entscheidungstraegern und ihren individuellen Ueberzeugungen muss daher in der internationalen Politik eine staerkere Bedeutung zukommen.
[en] The book on European emission trading, renewable energy law and the law of governmental environmental allowances covers the following issues: The European emission trading system and the European law on competition, the European emission trading system and competitive concerns; The European renewable energy law and the European law on competition, The European renewable energy law and competitive concerns; environmental protection the European competition policy.
[en] The scope of the book is on the one hand support for the power industry defining investment and sales strategies that intend optimum supply security in the view of the customer and on the other hand the information for energy and environmental politicians demonstrating the conflict of objectives. The following issues are covered: technical and organizational aspects of electricity supply, theoretical background of the security of electricity supply, security of supply for economic sections, security of electricity supply for private households: theoretical microeconomic approach, security of electricity supply for private households: method of defined preferences, security of electricity supply in the context of climate protection and nuclear phase-out.
[en] In the context of the “energy transition", national energy systems are currently undergoing fundamental structural changes. In this context, this work analyzes public acceptance of renewable energies and respective explanatory factors. It goes beyond existing studies by applying the same research design in four countries, which allows for comparative testing of various hypotheses from the research field across countries and technologies.
[en] Rare earth is not as rare as it name would indicate. It can be found on all continents worldwide and all parts of the world use products containing rare earth in everyday life. Without rare earth, key future technologies such as wind power stations, modern screens, or e-vehicles would be inconceivable or only available at a far higher price. Companies that manufacture products containing rare earth are therefore dependent on this raw material. Even though rare earth exists on all continents and potential deposits are known, over 90% of rare earth produced was mined in China in 2013. This occurred despite the fact that China's share of known rare earth reserves is only around 40 %. As a result, China has a kind of monopoly position in mining, refining, and thus also in the corresponding know-how. In the context of a need for supply reliability, countries and companies outside of China are examining (from a state, investor, and company perspective) to what extent it would make technical and economic sense to operate a European deposit. To this end, data is being compiled on 14 selected focus projects regarding required Investments, operating costs, and potential income in each case. This data will then be used to develop a DCF (discounted cash flow) model (with analogous assumptions and methods) for each project. This model would subsequently be used to determine achievable NPV, internal interest rate, and static amortization period for each project. Consolidating these 14 DCF moders into a single overarching comparative model could then show which of the projects - with the same prerequisites/assumptions - is the most attractive economically. The Swedish Norra Kaerr project is undergoing analysis as an example European deposit. Results for the base case (assumptions: 10 % discount factor, SEO prices averaged from Sep. 2014 to Aug. 2015) show that only 7 of the 14 focus projects could currently achieve a positive NPV at all. Even Norra Kaerr would not be profitable under the circumstances and would only achieve a 3.7% interest rate (EUR -155 million NPV). Taking into account maximization of the internal interest rate, the Steenkampskraal and Browns Range projects would be particularly interesting in this scenario. However, the highest NPV could be achieved with the Nolens project. In scenario 2, the assumption is that especially critical metals (dysprosium, neodymium, europium, terbium, and yttrium), that were previously defined, would increase in price due to high demand and limited supply. Therefore the basket prices of projects with a higher share of these critical SEO would especially increase. Under this assumption, Narre Kaerr could achieve a positive NPV (before taxes) if prices of critical metals were to increase by 25% and above. A price increase of 100% could result in an internal interest rate of 28% and a NPV of USD 682 million. In the third scenario, the discounting factor for Bach project is determined based an individual risks, such as e.g., specific country risks, project status. The Investment calculations are then executed with the respective discounting factor. A discounting factor of 15% was determined for Norra Kaerr. By breaking down the different risks (prices Sep. 2014 to Aug. 2015), four projects would have positive NPV, including Mount Weld. In contrast, Norra Kaerr would not achieve positive NPV. In all three scenarios, the Mountain Pass and Bokan projects would never achieve a minimum interest rate or a corresponding positive NPV under the given assumptions. Closure of the Mountain Pass deposit in 2015 due to unprofitability supports this theory. Sensitivity analyses show that the price has an especially high influence and that In the case of costs, increasing or decreasing operating costs has greater influence an NPV than a change in Investments. In summary, a deposit in Sweden's Norra Kaerr at 2015 prices does not make sense without further subsidies er external help, as no attractive minimum interest rate can be achieved. However, if the critical rare earth increases in price, production in Europe at Norra Kaerr would be possible economically. It investment calculations are executed for Norra Kaerr using prices from the last 5 years, then a minimum interest rate of over 10% could therefore have been achieved from 2010-2014 with annually averaged prices. This shows that a status quo perspective for such projects is neither sufficient nor expedient. It is more relevant to consider long-term developments in demand in the end product markets and necessary supply reliability for dependent companies. However, dependent companies will only be able to ensure the reliability they require from Europe with long-term contracts and commitments. In addition, participation by end product companies in a European deposit could create Investment stability an the one hand, and supply reliability an the other.
[en] Power sectors with weak or inadequate competition structures are the rule, despite numerous attempts at reform. But can afford modern economies this defect for a long time? Why can the implementation of competition are blocked so effectively? The author studied international reform experiences and opens up interesting insights that can also reflect on problems of the German energy turnaround: The difficulty of timing and coordination of the reform components, the development of resistance levels of individual interest groups, breach of contract as a rational alternative, causes unwanted price effects, shifting interest situations of major stakeholders, change dynamics impending regulatory risks, pending financing risks, stranded cost-conflict situations for power stations disconnected from the grid and facilities and instruments of a political and regulatory risk management for reforms. With numerous examples, background analyzes and instruments to reform analysis, this book is aimed at investors, policy planners and analysts.
[de]Stromsektoren mit schwachen oder unzulaenglichen Wettbewerbsstrukturen sind trotz zahlreicher Reformversuche die Regel. Aber koennen sich moderne Volkswirtschaften diesen Mangel dauerhaft leisten? Warum kann die Einfuehrung von Wettbewerb so wirksam blockiert werden? Der Autor untersucht internationale Reformerfahrungen und eroeffnet interessante Einsichten, die sich auch auf Problemlagen der deutschen Energiewende spiegeln lassen: Die Schwierigkeit des richtigen Timings und der Abstimmung der Reformteile, dem Aufbau von Widerstandslinien einzelner Interessensgruppen, Vertragsbruch als rationaler Alternative, Ursachen unerwuenschter Preiseffekte, sich verschiebenden Interessenslagen wichtiger Akteure, Veraenderungsdynamik drohender Regulierungsrisiken, schwebenden Finanzierungsrisiken, stranded-cost-Konfliktlagen fuer vom Netz genommene Kraftwerke und Moeglichkeiten und Instrumenten eines politisch-regulatorischen Risikomanagements fuer Reformen. Mit zahlreichen Beispielen, Hintergrundanalysen und einem Instrumentarium zur Reformanalyse richtet sich dieses Buch an Investoren, Politikplaner und Analysten.