Solar potential for the solar photovoltaic roof integration system in China explored by the geographic information system

This paper estimates the potential solar power for the solar photovoltaic Roof Integration System (RIS) using the Geographic Information System (GIS) method, taking into account the geographic distribution of solar irradiation and the estimate of costs for the RIS and identifies the distribution of potential solar energy radiating on the RIS and power. The total urban roof area is estimated to be 2957 million square metres by assuming five-story buildings. Based on the conversion efficiency of the RIS from solar energy to electric power that reached about 14%, the total potential power of this system in the urban regions of China can attain about 1.9 × 1018 J, thus lessening the cumulative emission at approximately 5.3 × 108 tons of carbon dioxide (CO2). Also, the results show that the west is the most suitable region for the RIS, where the highest electricity cost can be reached owing to the most intense irradiation. However, this large need of power will counteract the high cost induced by low irradiation to promote the application of the RIS in eastern China, where the cost of electricity is the highest.