Reassessment of the potential for centralized and distributed photovoltaic power generation in China: On a prefecture-level city scale

The successful development of solar energy primarily depends on the scientific and effective evaluation of the photovoltaic power generation potential. This study re-estimated the installed potential of centralized large-scale and distributed small-scale photovoltaic power stations in 449 prefecture-level cities in China based on a geographic information system and Google Earth Engine combined with Baidu map data and related geographic information data. The factors considered in selecting the areas suitable for photovoltaic power generation were economy, terrain, environment for the centralized stations; illumination time, roof type, and shadow obstacles of the building for distributed systems. The results showed that a total area of 583 thousand km2 in China can be utilized to install solar panels, with a technical potential of approximately 55.1 TW. In particular, the technical potential of the centralized power stations was approximately 42.8 TW, primarily distributed in Naqu, Tibet and Haixi, Qinghai. The potential of the distributed systems was approximately 12.3 TW (including 4.9 TW for flat roof, 3.5 TW for pitched roof, and 3.9 TW for building facade), primarily concentrated in Yulin and Guigang, Guangxi; and Meizhou, Guangdong. The findings can clarify the spatio-temporal distribution of photovoltaic potential nationwide and provide decision support for regional planning.