In this paper, a new method is proposed for optimal scheduling a micro-grid system consist of generation units and demand response resources in order to minimize operating cost by independent system operators. In the presented mathematical model with new formulation, the load uncertainty is considered. The optimization problem is composed of Mixed Integer Nonlinear Programing (MINLP), which is analyzed with commercial software GAMS. The numerical studies are done on a 6-buses network. Modeling and analyzing are done in two states, with certain data and in a stochastic environment. The impact of demand response with different level of participation is discussed. The results show considerable effect of uncertainties in parameters and costumers participation.
