Oligopoly equilibria in electricity contract markets

Abstract

This paper examines the implications of forward contracting on oligopoly environments by extending the model of Allaz and Vila to an environment with multiple firms and increasing marginal cost. Estimates of key parameters of this model are taken from existing electricity markets to predict the market impact of one round of public contracting, such as those seen in auctions for retail provision and resource procurement. The results imply that, when forward contracts are present, the importance of supplier concentration is greatly magnified relative to other determinants unilateral market power such as demand elasticity. © 2007 Springer Science+Business Media, LLC.