To promote renewable energy integration in China's power grids, the Chinese government has set forth renewable portfolio standards. This paper analyzes the feasibility of renewable portfolio standard from the perspectives of the supply and demand of renewable electricity. A multiple regression model is established to predict the demand of 30 provinces for renewable electricity in 2020 under various scenarios. The renewable power supply is measured based on the provincial plans for renewable electricity demand. The results suggest four main conclusions. (1) If all provinces can implement their respective renewable energy planning, the renewable power supply will exceed the renewable portfolio standard targets by about 488 TWh (including 155 TWh of non-hydro power). (2) Guangdong, Shanghai, Jiangsu, Zhejiang and Chongqing will experience the greatest lack of renewable electricity; the shortfall in these provinces will reach 320 TWh, representing 77% of the total renewable portfolio standard target. (3) The greatest shortfall of non-hydro power will occur in Beijing, Jiangsu, Tianjin and Zhejiang; this shortfall will be approximately 39 TWh, accounting for 69% of the total non-hydro power shortfall. Moreover, the non-hydro power supply will far exceed the policy targets in Xinjiang, Qinghai, Inner Mongolia and Gansu. (4) China's renewable portfolio standard policy will further promotes the optimal allocation of renewable energy resources among provinces via inter-provincial transactions.