Transactions evaluation and unit commitment in a bilateral electricity market using genetic algorithms

Short term optimal operation planning and the evaluation of multiple power transactions (scheduled contracts for power exchange at a specific time interval) in a deregulated environment based on a bilateral market model is a complex optimization problem for the planning personnel of electric utilities. With regard to time dependent constraints and costs in unit commitment (UC), the transaction evaluation problem and UC are coupled and therefore must be solved simultaneously. In this paper a new solution method based on genetic algorithm (GA) is presented. Due to the flexibility of GA, it is possible to select optimal transactions within the UC algorithm. The basic idea of the new method is to find an optimal load curve by means of an evolutionary process using an optimal combination of proposed transactions simultaneous with optimal scheduling of generation units. The capabilities of this approach are illustrated by means of a 26-unit system with a set of proposed transactions that includes exchange with pump storage units and various forms of transactions such as peak. off-peak and base load.