Optimization of economic/emission load dispatch for hybrid generating systems using controlled Elitist NSGA-II

A model is developed for stochastic economic/emission dispatch of thermal/wind/solar hybrid generation system taking into account cost of modern thermal units with multiple valves point effect, polluting gases emission and factors for both overestimation and underestimation of available wind and photovoltaic power. The technique proposed in this work uses novel probability density functions (pdf) of wind power and clearness index to model the wind power and solar irradiance. A multi-objective controlled elitistNSGA-II procedure is proposed to derive a set of Pareto-optimal hybrid system configuration in terms of cost and emission with good diversity. Controlled elitist-NSGA-II favors, not only individuals with better fitness value (rank) as in elitist NSGA-II but also individuals that can help increase the diversity of the population even if they have a lower fitness value. The best compromise solution has been obtained using Fuzzy cardinal priority ranking. Optimal solutions are presented for various values of the input parameters, and these solutions demonstrate that the allocation of system generation capacity may be influenced by multipliers related to the risk of overestimation and to the cost of underestimation of available wind and solar power. A numerical example, including six fossil-fuel-fired generators (FFGs), two Wind Energy Conversion Systems (WECS), and two Photo Voltaic (PV) systems is presented. To validate the effectiveness of the algorithm, results are compared with techniques given in literatures. (C) 2013 Elsevier B.V. All rights reserved.