An evolutionary optimization technique based methodology has been proposed in this paper to sustain the total generation cost even in contingent states of a power network for consumer welfare. The alteration of generation cost during contingency is quite evident which makes the consumers suffer economically due to rise of the level of congestion and price of electricity. The aim of this proposed methodology is to minimize the deviations of generation cost, during contingency, from a preferred value by re-allocation of generation schedule with a controlled load curtailment technique and hence relieving the lines from overloading for congestion management. It has been demonstrated that, on application, the proposed methodology can improve the operating conditions of the system apart from optimizing the price volatility of electrical power market. The methodology has been tested on a standard benchmark system and the comprehensive simulation results looked promising. © 2011 IEEE.