Solar energy curtailment in China: Status quo, reasons and solutions

Recently, parts of the solar energy (especially photovoltaic power station) could not be connected to power system, leading to a serious solar energy curtailment problem. Generally speaking, in 2017, 91.4% of the rejected solar energy occurs in the northwestern China with the total electricity reaching 6670 GW h. Because China is of a large amount of the installed solar capacity, the existing large-scale solar energy curtailment problem have greatly affected the development of the solar power industry (e.g. the investors' profits) and the long-term development of the China's clean energy policy. In this review, based on the statistical data released by the authorities, the current status of the solar energy curtailment are reviewed with a detailed analysis of the reasons from the aspects of power generation and electric grid. This review focuses on the cases of the two typical provinces (Gansu province and Xinjiang Uygur Autonomous Region) with large-scale solar energy curtailment together with related analysis. Several practical solutions are also proposed to further relieve the problem in the near future. Detailed comparisons between different schemes are also given in order to help policy makers in China and also other countries for the further development of the solar power generation.