To provide high - quality and reliable power supply at the lowest possible cost while operating to meet the limits and constraints imposed on the generating units is the main objective of electric power utilities. The economic load dispatch (ELD) is essential in the operation of power system. A global optimization technique ‘Genetic Algorithm’ (GA) is presented. The algorithm utilizes information of candidate solutions to evaluate their optimality. As a case study, this technique is applied to the solution of the economic dispatch (ED) problem of thermal generating units. A smooth quadratic function is used to represent the fuel cost of each generating unit. The B-coefficient method is used to model the transmission losses. Using two different methods “Lambda-Iteration method” and “Genetic Algorithm method” the cost function is derived at different loads. These two different methods proposed to reduce the generation cost using data of different units. GA has been identified as more suitable than LI. It is free from nature of graph of the cost function. It exhibits very good performance on the majority of the problems applied.
Key words: ELD, GA, ED, LI