Zugl.: Ilmenau, Techn. Univ., Diss., 2008

Zugl.: Potsdam, Universiẗat, Diss., 2008.

Die von der Juristischen Fakultät der Universität Würzburg 1983 angenommene Habilitationsschrift erschließt aus einer Darstellung von geschichtlicher Entwicklung und Gegenwart von grenzüberschreitenden Investitionen - als Vorgang (Kapital- und ähnliche Transaktionen) wie als Ergebnis (Kapitalanlage) - deren aktuelle Gestaltungstypen und Regelungsmuster (einschließlich des Rechtsschutzes bei Enteignungen, anderen Beeeinträchtigungen und Diskriminierungen). Sie berücksichtigt dabei sowohl die völkerrechtliche als auch die staatliche Rechtsetzung und Praxis, um am Ende das Recht der internationalen Investitionen als Teil eines Internationalen bzw. Weltwirtschaftsrechts(systems) zu verankern.

The increasing share of renewable energies in the power sector influences the economic viability of investments in new conventional power plants. Many studies have investigated these issues by considering power plant operation or the long-term development of the power plant fleet. However, power plant decommissioning, investment and operation are intrinsically linked. This doctoral thesis therefore presents a modelling framework for an integrated consideration of power plant decommissioning, investment and operation. In a case study focusing on Germany, the effects of the integration of renewable energies on power plant decommissioning, investment and operation are evaluated in the context of different assumptions regarding the remaining lifetime of nuclear power plants. With regard to the use of nuclear power, a phase-out scenario and a scenario with lifetime extension of nuclear power plants (by on average 12 years) are considered. The results show that static decommissioning (i.e. considering fixed technical lifetimes) underestimates the capacity available in the power sector in the scenario without lifetime extension since retrofit measures (versus decommissioning) are not taken into account. In contrast, capacity available in the case of nuclear lifetime extension is overestimated since mothballing (versus regular operation) is not considered. If the impact on decommissioning decisions of profit margins accrued during power plant operation are considered (“dynamic decommissioning”), the electricity price reduction effect due to a lifetime extension is reduced by more than half in comparison to static decommissioning. Scarcity situations do not differ significantly between the scenarios with and without lifetime extension with dynamic decommissioning; in contrast, there is a significantly higher need for imports without lifetime extension with static decommissioning. The case study demonstrates that further system flexibility is needed for the integration of renewable energies. It can be further concluded that the share of flexible power plants is higher with the phase-out of nuclear power plants. With regard to the decommissioning dynamics, the phase-out can be considered as beneficial for the economic viability of fossil power plants. Furthermore, the phase-out does not, overall, lead to environmental disadvantages in the medium term, but may be beneficial in the long run since lock-in effects are avoided. Further research is required with regard to the consideration of future flexibility options and a new market design. / Der steigende Anteil erneuerbarer Energien beeinflusst die Wirtschaftlichkeit von Investitionen in neue konventionelle Kraftwerke. Zahlreiche Studien haben diese Aspekte in Bezug auf den Kraftwerksbetrieb oder die langfristige Entwicklung des Kraftwerksparks untersucht. Stilllegungen, Investitionen und Betrieb im Kraftwerkspark bedingen jedoch einander. Aus diesem Grund wird in dieser Doktorarbeit ein Modellierungsansatz für eine integrierte Betrachtung von Kraftwerksstilllegung, -investition und -betrieb vorgestellt. In einer Fallstudie für Deutschland werden die Auswirkungen einer Integration erneuerbarer Energien auf Kraftwerksstilllegung, -investition und -betrieb im Zusammenhang mit unterschiedlichen Annahmen über die Restlaufzeit von Kernkraftwerken untersucht. Bezogen auf die Nutzung der Kernenergie wird hierbei ein Ausstiegsszenario sowie ein Laufzeitverlängerungsszenario (Verlän-gerung der Laufzeit um durchschnittlich 12 Jahre) betrachtet. Die Ergebnisse zeigen, dass die statische Stilllegung (d.h. die Betrachtung fester technischer Lebensdauern) im Fall eines Verzichts auf die Laufzeitverlängerung die im Kraftwerkspark verfügbare Leistung unterschätzt, da Retrofit-Maßnahmen (im Vergleich zur Stilllegung) nicht berücksichtigt werden. Die verfügbare Leistung im Falle einer Laufzeitverlängerung wird dagegen überschätzt, da die Möglichkeit der Kaltreserve (im Vergleich zum regulären Betrieb) vernachlässigt wird. Werden die Rückwirkungen der im Betrieb erwirtschaftbaren Deckungsbeiträge auf Stilllegungsentscheidungen (“dynamische Stilllegung”) betrachtet, so wird der strompreissenkende Effekt durch die Laufzeitverlängerung im Vergleich zur statischen Stilllegung mehr als halbiert. Knappheitssitutationen unterscheiden sich nicht wesentlich mit und ohne Laufzeitverlängerung im Fall der dynamischen Stilllegung, während bei statischer Stilllegung ohne Laufzeitzeitverlängerung ein deutlich größerer Importbedarf besteht. Die Fallstudie zeigt, dass weitere Systemflexibilitäten für die Integration erneuerbarer Energien benötigt werden. Der Anteil flexibler Kraftwerke ist größer im Fall des Kernenergieausstiegs. Der Kernenergieausstieg wirkt sich in Bezug auf die Stilllegungsdynamik positiv auf die Wirtschaftlichkeit fossiler Kraftwerke aus. Insgesamt führt der Kernenergieausstieg zu keinen mittelfristig nachteiligen Umwelteffekten, er kann sich jedoch langfristig positiv auswirken, da Lock-in-Effekte vermieden werden. Es besteht weiterer Forschungsbedarf in Bezug auf die Berücksichtigung künftiger Flexibilitätsoptionen und ein neues Marktdesign.

The first part analyzes an Endogenous Business Cycle model with embodied technological change. Households take an optimal decision about their spending for consumption and financing of R&D. The probability of a technology invention occurring is an increasing function of aggregate R&D expenditure in the whole economy. New technologies bring higher productivity, but rather than applying to the whole capital stock, they require a new vintage of capital, which first has to be accumulated before the productivity gain can be realized. The model offers some valuable features: Firstly, the response of output following a technology shock is very gradual; there are no jumps. Secondly, R&D is an ongoing activity; there are no distinct phases of research and production. Thirdly, R&D expenditure is pro-cyclical and the real interest rate is counter-cyclical. Finally, long-run growth is without scale effects. The second part analyzes a RBC model in continuous time featuring deterministic incremental development of technology and stochastic fundamental inventions arriving according to a Poisson process. In a special case an analytical solution is presented. In the general case a delay differential equation (DDE) has to be solved. Standard numerical solution methods fail, because the steady state is path dependent. A new solution method is presented which is based on a modified method of steps for DDEs. It provides not only approximations but also upper and lower bounds for optimal consumption path and steady state. Furthermore, analytical expressions for the long-term equilibrium distributions of the stationary variables of the model are presented. The distributions can be described as extended Beta distributions. This is deduced from a methodical result about a delay extension of the Pearson system.

Techn. Univ., Diss--Berlin, 2007.

Calif., Univ., Diss.--Berkeley, 2004. / Kopie, ersch. im Verl. UMI, Ann Arbor, Mich. - Enth. 3 Beitr.

Univ., Diss.--Augsburg, 2004.

Purpose - This bachelor thesis compares high-speed rail (HSR) transport with air transport. The investigation considers physical fundamentals, energy consumption, environmental impact, infrastructure and investment, market situations, passenger's selection criteria to choose transportation options, and overall economics. --- Methodology - The thesis combines an investigation of physical principles with a literature review. --- Findings - Steel wheels on steel rails show by far less rolling resistance to support the train's weight than drag due to lift (induced drag) to support the aircraft's weight. This leads to less energy consumption. HSR trains use electricity from an overhead line. Hence, the environmental impact of HSR also depends much on how the electricity is produced. Airplanes only need an air traffic control environment to connect airports. In contrast, HSR needs infrastructure to connect stations. The amount of necessary infrastructure depends on the geological conditions. For example, crossing mountains means high investment. Longer passages over water are infeasible for HSR. High-speed rail is superior to air transport when connecting megacities because the trains have higher transport capacity, offer higher service frequencies and mission reliability, shorter total travel time, shorter access time to stations, shorter unproductive waiting time in stations and potentially lower travel costs. HSR is a strong competitor to airline services and has replaced some short range flights. A comparison of HSR in different world regions shows differences in the market situation and in passenger's selection criteria for transportation options. --- Research limitations - The potential of high-speed rail was investigated mainly on busy routes with high service frequencies. A comprehensive network comparison between high-speed trains and airplanes was not done and could lead to somewhat different results. --- Practical implications - The report tries to contribute arguments to the discussion about alternatives to air travel. --- Social implications - With more knowledge people can make an educated choice between transport options, can vote with their feet, and can take a firm position in the public discussion. --- Originality/value - A general comparison of HSR and air transport from physical fundamentals to economics seemed to be missing.

The first part analyzes an Endogenous Business Cycle model with embodied technological change. Households take an optimal decision about their spending for consumption and financing of R&D. The probability of a technology invention occurring is an increasing function of aggregate R&D expenditure in the whole economy. New technologies bring higher productivity, but rather than applying to the whole capital stock, they require a new vintage of capital, which first has to be accumulated before the productivity gain can be realized. The model offers some valuable features: Firstly, the response of output following a technology shock is very gradual; there are no jumps. Secondly, R&D is an ongoing activity; there are no distinct phases of research and production. Thirdly, R&D expenditure is pro-cyclical and the real interest rate is counter-cyclical. Finally, long-run growth is without scale effects. The second part analyzes a RBC model in continuous time featuring deterministic incremental development of technology and stochastic fundamental inventions arriving according to a Poisson process. In a special case an analytical solution is presented. In the general case a delay differential equation (DDE) has to be solved. Standard numerical solution methods fail, because the steady state is path dependent. A new solution method is presented which is based on a modified method of steps for DDEs. It provides not only approximations but also upper and lower bounds for optimal consumption path and steady state. Furthermore, analytical expressions for the long-term equilibrium distributions of the stationary variables of the model are presented. The distributions can be described as extended Beta distributions. This is deduced from a methodical result about a delay extension of the Pearson system.