The increasing penetration of renewable energy sources (RES), battery energy storage systems (BESS), and other loads native to DC, raises the question if a DC backbone topology may be more suitable compared to the commonly used AC. A number of studies that focused on this question, demonstrate a wide range of results that depending on the application and external conditions simulated. In this work, simulated DC and AC topologies are tested in an office building located in Belgium using a modelling framework developed in Modelica. The building is assumed to have a large penetration of building-integrated photovoltaics (BIPV) and battery energy storage systems (BESS) and a wide range of key performance indicators (KPI) are used to quantify the comparison. The DC topologies demonstrate increased performance when the BIPV system produces large amounts of power. The performance gains may be further enhanced by sizing optimally the less efficiency system components.
Keywords Building-Integrated Photovoltaics (BIPV), Electrical configuration, Modelling, Modelica, Building energy simulation