This dissertation applies a variety of quantitative methods to European electricity market data to enable us to detect, understand, and eventually mitigate market imperfections. The empirical data indicate that market power and barriers to cross-border trade partially explain today’s market failures. Briefly, the five key findings of this dissertation are: First, we observe a decoupling between German electricity prices and fuel cost, even though British electricity prices are largely explained by short-run cost factors. Second, we demonstrate that rising prices of European Union emission allowances (EUA) have a greater impact on German wholesale electricity prices than falling EUA prices. Third, we reject the assumption of full integration of European wholesale electricity markets in 2002-2006; for several pairs of countries, the weaker hypothesis of (bilateral) convergence is accepted (i.e. efforts to develop a single European market for electricity have been only partially successful). Fourth, we observe that daily auction prices of scarce cross-border transmission capacities are insufficient to explain the persistence of international price differentials. Empirically, our findings confirm the insufficiency of explicit capacity auctions as stated in the theoretical literature. Fifth, we identify inefficiencies in the market behavior for the interconnector linking France and the United Kingdom (UK), for which several explanations, including market power, may be plausible.

This dissertation applies a variety of quantitative methods to European electricity market data to enable us to detect, understand, and eventually mitigate market imperfections. The empirical data indicate that market power and barriers to cross-border trade partially explain today’s market failures. Briefly, the five key findings of this dissertation are: First, we observe a decoupling between German electricity prices and fuel cost, even though British electricity prices are largely explained by short-run cost factors. Second, we demonstrate that rising prices of European Union emission allowances (EUA) have a greater impact on German wholesale electricity prices than falling EUA prices. Third, we reject the assumption of full integration of European wholesale electricity markets in 2002-2006; for several pairs of countries, the weaker hypothesis of (bilateral) convergence is accepted (i.e. efforts to develop a single European market for electricity have been only partially successful). Fourth, we observe that daily auction prices of scarce cross-border transmission capacities are insufficient to explain the persistence of international price differentials. Empirically, our findings confirm the insufficiency of explicit capacity auctions as stated in the theoretical literature. Fifth, we identify inefficiencies in the market behavior for the interconnector linking France and the United Kingdom (UK), for which several explanations, including market power, may be plausible.

Limit-Orderbücher sind das Standardinstrument der Preisbildung in modernen Finanzmärkten. Während Strom traditionell in Auktionen gehandelt wird, gibt es Intraday Strommärkte wie beispielsweise den SIDC-Markt, in welchem Käufer und Verkäufer über Limit-Orderbücher zusammentreffen. In dieser Arbeit werden wir stochastische Modelle von Limit-Orderbüchern auf der Grundlage der zugrundeliegenden Marktmikrostruktur entwickeln. Einen besonderen Schwerpunkt legen wir dabei auf die Berücksichtigung besonderer Merkmale der Intraday-Strommärkte, die sich zum Teil deutlich von denen der Finanzmärkte unterscheiden. Die in dieser Arbeit entwickelten Modelle beginnen mit einer realistischen und mikroskopischen Beschreibung der Marktdynamik. Große Preisänderungen über kurze Zeiträume werden ebenso berücksichtigt wie begrenzte grenzüberschreitende Aktivitäten. Diese mikroskopischen Modelle sind im Allgemeinen zu rechenintensiv für praktische Anwendungen. Das Hauptziel dieser Arbeit ist es daher, geeignete Approximationen dieser mikroskopischen Modelle durch sogenannte Skalierungsgrenzprozesse herzuleiten. Zu diesem Zweck werden sorgfältig Skalierungsannahmen formuliert und in die mikroskopischen Modelle eingebaut. Diese Annahmen ermöglichen es uns, ihr Hochfrequenzverhalten zu untersuchen, vorausgesetzt, dass die Größe eines einzelnen Auftrags gegen Null konvergiert, während die Auftragseingangsrate gegen unendlich tendiert. Die Kalibrierung mathematischer Modelle ist aus Anwendersicht eines der Hauptanliegen. Dabei ist bekannt, dass Änderungspunkte (abrupte Schwankungen) in hochfrequenten Finanzdaten vorhanden sind. Falls sie durch endogene Effekte verursacht wurden, muss bei der Schätzung solcher Änderungspunkte die Abhängigkeit von den zugrundeliegenden Daten berücksichtigt werden. Daher erweitern wir im letzten Teil dieser Arbeit die bestehende Literatur zur Erkennung von Änderungspunkten, so dass auch zufällige, von den Daten abhängige Änderungspunkte gehandhabt werden können. / Limit order books are the standard instrument for price formation in modern financial markets. While electricity has traditionally been traded through auctions, there are intraday electricity markets, such as the SIDC market, in which buyers and sellers meet via limit order books. In this thesis, stochastic models of limit order books are developed based on the underlying market microstructure. A particular focus is set on incorporating unique characteristics of intraday electricity markets, some of which are quite different from those of financial markets. The developed models in this thesis start with a realistic and microscopic description of the market dynamics. Large price changes over short time periods are considered, as well as limited cross-border activities. These microscopic models are generally computationally too intensive for practical applications. The main goal of this thesis is therefore to derive suitable approximations of these microscopic models by so-called scaling limits. For this purpose, appropriate scaling assumptions are carefully formulated and incorporated into the microscopic models which allow us to study their high-frequency behavior when the size of an individual order converges to zero while the order arrival rate tends to infinity. Calibration of mathematical models is one of the main concerns from a practitioner’s point of view. It is well known that change points (abrupt variations) are present in high-frequency financial data. If they are caused by endogenous effects, the dependence on the underlying data must be considered when estimating such change points. In the final part of this thesis, we extend the existing literature on change point detection so that random change points depending on the data can also be handled.