Potential estimation of rooftop photovoltaic with the spatialization of energy self-sufficiency in urban areas

Abstract

The distribution of rooftop PV is spatial heterogeneity with the location of buildings. With the assistance of geographic information systems, this study proposed an integrated research framework for the geo-spatial potential assessment of PV systems on the roof of urban buildings as well as its feasibility analysis. Furthermore, a geo-spatialization of electricity self-sufficiency rate is also introduced to explore the contribution of rooftop PV on urban energy security. The proposed approach was verified by a case study in the central area of Wuhan, China with a 100 m spatial resolution. The results show that the maximum annual PV power generation potential in the central area of Wuhan is 10,757 GWh, which could satisfy 31.83% of local energy consumption. A 100% deployment of rooftop PV would also lead to a great carbon emission reduction, i.e. 8.62 million tons per year, with an annual total cost of 8.07 bn USD. According to the distribution characteristics of the PV self-sufficiency rate on the map, priority is given to investing in the peripheral areas of the city with the higher return. It is estimated that when the PV conversion rate increases by 5%, the peak self-sufficiency rate to the area will increase by 20% in Wuhan. Moreover, if the conversion rate of PV system reaches 47.13%, a fully utilized rooftop in Wuhan for PV deployment could meet the local electricity demand, which implies a 100% electricity self-sufficiency. This study is helpful to understand the spatial heterogeneity of rooftop PV in urban areas, and could serve as the guidelines for local governments to develop renewable energy in a sustainable way.

Keywords

• Rooftop PV energy
• Energy self-sufficiency rate
• Geo-spatialization
• Geographic information system