Measuring dynamics of solar energy resource quality: Methodology and policy implications for reducing regional energy inequality

Abstract

Solar energy utilization has been widely recognized as the most promising solution for achieving the global and regional carbon neutral targets. While existing literature on assessment of the solar energy resource mostly focuses on the current availability of energy quantity, the dynamic quality characteristics of reliable energy supplies are always neglected. This research presents a holistic spatiotemporal assessment methodology to quantify the solar energy resource quality (SERQ) from a quantity and quality coupled perspective. Specifically, we used the time-series daily meteorological reanalysis data, annual land use/cover, and nighttime light data during 1992–2018 to investigate the dynamic properties of SERQ at the 0.125° × 0.125° grid cell level across China. The validation process based on exiting solar power farms was conducted to analyze the applicability of proposed method in site selection. Our findings revealed that the annual solar energy potential in China was estimated at 66 PWh with the high resource quality level (SERQI>0.6). Furthermore, the outcomes of resource quality evaluation are more sensitive to the power load accessibility index. The involvement of energy quality dimension would reduce regional energy inequality in China. Thus, we highlight the necessity of improving the long-distance power transmission and energy storage infrastructures. Mapping the SERQ at the country level could provide investors and decision makers with useful insights to develop appropriate energy planning and incentive policies.