Research on optimization method of CCHP system coupled with renewable energy Ligai Kang, Dongxiang Sun, Wei Zhao, Wenjing Wang, Xiaojing Wu, Xu Zhang, Yang Yang and Yijun Wang Sci. Tech. Energ. Transition, 79 (2024) 70 Published online: 27 September 2024 DOI: 10.2516/stet/2024069