With the proposal of emission peak and carbon neutrality, the capacity of conventional power sources will decrease while the capacity of renewable energy (RE) will increase, which will bring challenges to the peak regulating of power systems. In this paper, a planning model aiming at minimizing the total cost is proposed to optimize RE and energy storage system (ESS) capacity, which can make their output in the track of load curves. Evaluation indexes are defined from the dimensions of volatility and anti-peak regulating characteristics to analyze the planning results. Then an actual power system in China is used as an example to verify the effectiveness of the model. The results show that the model can make differential configuration of RE and ESS according to the load characteristics and resource conditions in different regions as well as reduce the volatility and anti-peak regulating characteristics of the complementary system.