Nodal market power assessment in electricity markets

Market power assessment is an important aspect of electric market analysis and operation. Market power problems are more complicated in an electric market than those in other markets due to the specific properties of electricity. This paper investigates market power problems and the related solution techniques in an electric power market. The impact of load variation, the size of a power supplier and random failures on market power has been investigated. The geographic difference of market power caused by network constraints has been considered. Must run share (MRS) and nodal must-run share (NMRS) have been proposed to represent system and local market powers respectively. An optimization technique and the topological analysis of power flow have been used to determine the MRS and NMRS. Expected nodal must-run share (ENMRS) has been proposed to represent the impact of random failures on market power and the associated risk of customers paying a high price due to the exercise of market power. The contingency enumeration and probabilistic technique have been used to determine the ENMRS. The IEEE Reliability Test System is analyzed to illustrate the proposed indices and techniques.