Distributed photovoltaics (PVs) play an important role in promoting renewable energy development. Integrating distributed PVs into a microgrid system can fully improve the energy efficiency of the microgrid. Previous studies on the self-sufficiency of distributed microgrids have rarely taken the load characteristics of customers and the output characteristics of distributed energy sources into account. This paper focuses on the impact of the scale of microgrids and the capacity of rooftop PVs on the system energy self-sufficiency indicator. Residential load characteristics and output characteristics of rooftop PVs are analyzed, and then we propose indicators to measure PVs energy self-sufficiency and PVs energy consumption capacity. The results show that a general pattern how microgrid's scale and the capacity of rooftop PVs affect system energy self-sufficien. The research results are important for effective planning and design of residential rooftop PV microgrids.

Distributed photovoltaics;microgrids;residential load characteristics;photovoltaic output characteristics;energy self-sufficiency