COMPETITION IN ELECTRICITY MARKETS: RETAILERS, GENERATORS AND TECHNOLOGIES

The objective of this thesis is to answer to three questions raised by the wave of reform in electricity industries: has retail liberalization achieved its objectives in European Union? How traditional and renewable generators compete in a liberalized market? What is the impact on congestion and zonal price differences of increased production from renewable intermittent sources in Italy? The first chapter provides a mid-term evaluation of liberalization of electricity retailing in Europe. We propose a comprehensive theory on retail liberalization and test its consistency with the practice in European Union. The analysis highlights the presence of an oligopolistic supply structure, a limited level of customer engagement in the market and asymmetries in the rate and speed of cost-pass through. The attribution of the Default/Last Resort service through an auction mechanism seems the best solution to favor the development of competition. In the second chapter we study the strategic interactions between a traditional generation technology and a renewable one characterized by an intermittent availability of capacity. We employ a modified version of the Dixit model for entry deterrence with two post entry competition settings: the Cournot framework in a two stage game and the dominant firm-competitive fringe setting in a three stage game. In both cases, the analysis suggests that the renewable generator exploits the merit order rule to crowd out the production of its rival. In the third chapter we analyze the impact of renewable generation on congestion and zonal price differences in Italy. Using a unique database we estimate two econometric models on five zonal pairings: a multinomial logit model for the occurrence and direction of congestion and an OLS model for the size of paired-price differences. The analysis shows that in an importing region the effect of a larger local renewable supply is to decrease (increase) the probability of congestion in entry (exit). Increasing renewable generation seems to have a significant impact on the islander zones, decreasing (increasing) the level of positive (negative) price differences.