An efficient operating policy for committed units (CU) in order to meet the load demand is very important for power system operators.Optimum Power Dispatch (OPD) problems help to find such suitable operating policies for CUs without violating system and unit constraints. Minimization of fuel cost or reduction of amount of pollutants emission or optimization of both fuel cost and emission are the objectives of OPD problems.Based on the objectives, OPD problems are classifieds and are briefly discussed in this paper. The OPD problem of hybrid power system with and without solar and wind energies is considered and this paper illustrates the OPD with MATLAB simulations
