Abstract: Developing single-type renewable energy source in energy bases will bring about many problems such as energy waste and low equipment utilization. As the continuous maturity of various power generation technologies, the optimal configuration and collaborative development of complementary power sources in energy bases are seen as effective ways to solve these problems. Firstly, based on the complementary characteristics between various power sources, this paper proposes a novel concept of the composite power plant (CPP), whose complementary mechanism and external characteristics for planning are studied. Secondly, a method considering multi-energy complementary characteristics and external requirements is put forward to optimize the energy base configuration. Furthermore, in the tri-level iterative operation simulation mechanism of the planning scheme, a generation expansion planning method including CPP is designed. Finally, numerical results verify the rationality of the proposed CPP configuration model and planning method, which can provide theoretical guidance and technical support for optimized configuration of the energy base.