Optimal operation of commercial building microgrids using multi-objective optimization to achieve emissions and efficiency targets

This paper presents an optimization model for optimal energy management of commercial building microgrid (μG) systems. The objectives are to increase efficiency of energy utilization, minimize operational costs and reduce environmental impacts of energy utilization in commercial buildings. Thus, mathematical models of a Combined Cooling, Heating, and Power (CCHP) μG including gas-fired Internal Combustion Engines (ICEs), Gas Boilers (GB), Micro Turbines (MTs), Fuel Cells (FCs), Heat Exchanger (HE), and Absorption Refrigeration (AR) are developed. Also, mathematical models for solar PhotoVoltaic (PV) generation, thermal energy storage, and battery storage devices are formulated. Based on the developed models, a multi-objective optimization problem is formulated to optimally operate these multi-carrier hybrid AC/DC μGs, minimizing their energy costs and Greenhouse Gas (GHG) emissions. The proposed method is applied to a commercial building μG to investigate the best strategies to operate the μG to achieve Department of Energy's (DOE's) 2020 emissions and efficiency targets for μGs. The presented simulation case studies show promising results by reducing total costs and attaining the efficiency and emissions reductions targets.