New Ex-ante Indices of Market Power

This paper deals with introducing new ex-ante indices of market power which measure potential of each generator in exercising market power. These indices consider competitors' offer price as an important factor affecting incentive of generator to exercise market power. In deregulated electricity market, there exists two strategies adopted by generators to exercise market power which are separated from each other. Therefore, two different indices are introduced in order to separate these two strategies named physical withholding and financial withholding. New separated indices help market monitoring to predict players' reaction more precisely before market constitution. The Proposed indices are calculated for generators of a test system and the results are discussed.