Market Power in Electricity Industry Restructurings

In recent years there has been a worldwide trend towards the deregulation and restructuring of electricity supply industries (hereinafter" electricity industries").'This transformation, propelled by technological changes which have undermined economies of scale in some industry segments and supported by the current teachings of economics, has been characterized by a move from command-based regulation 2 and natural monopoly models towards increased market governance and deintegrated market structures. However, market power issues have not lost their importance. Instead, they may have more significance now than ever. In fact, new electricity industry structures raise a whole range of market power issues. Transmission and distribution segments are characterized as natural monopolies, the most concentrated of all market structures, which cannot be eliminated simply through a change of market …