With ability to enhance the reliability and security in the power supply, reduced greenhouse gas emissions, and integration of renewable energy sources Microgrids are becoming more popular in electrical systems. However, large scale integration of renewable energy sources can cause power imbalances and uncertainties in the output of electrical interaction sources. Therefore, obtaining an optimal solution for Economic Dispatch (ED) of Distributed Energy Resources (DERs) is critical. While traditional ED models do not include the environmental effects of power generation, there is a need for a CEED (Combined Economic and Emission Dispatch) model that addresses both economic and environmental objectives in the ED problem