Abstract: Energy saving, emission reduction and energy restructuring in the construction industry are crucial for our country to achieve carbon peaking and carbon neutrality goals. The efficient utilization of regional energy supply through multi-energy complementarity is an important approach to achieving low-carbon development in urban construction. As a clean and high-quality energy source, natural gas plays a significant role in adjusting the energy structure of regional energy supply. CCHP system enables full cascade utilization of energy. However, their promotion and development are constrained by factors such as gas and electricity prices. This study focuses on a river water source heat pump and CCHP system coupling for regional energy supply projects. Based on current gas and electricity prices in Hunan Province, economic comparisons and analyses are conducted for various CCHP system schemes under different operation strategies and capacities to determine optimal capacity and operation schemes. Additionally, a critical value for the gas-power ratio required for economically viable operation of the CCHP system is proposed to guide subsequent project operations.