**2. Problem Formulation**

DGs based on renewable energies are the main technologies that greatly affect the operation of the MG units. Because of their stochastic nature, optimal MG operation has to effectively handle their types and associated uncertainties in hourly basis. In this section, an optimization scheme is presented for the techno-economic and environmental operation of MGs that are established with several DGs based on renewable energies, including PV/WT/BG considering hourly variable load demand.
