Detecting and understanding co-benefits generated in tackling climate change and environmental degradation in China

China is facing the challenge of climate change and environmental protection in line with the promotion of sustainable development goals. Climate, environmental, and economic policy can each individually impact the effectiveness of other policies in the process of implementation. Understanding synergies among policy measures and identifying the co-benefits of environmental sustainable development generated by them is the focus of the paper. Because of existing restrictions in current research methods, the research community lacks the capacity to detect the interrelation among environmental, economic, and social development. Co-benefit research has gradually become an important area on sustainable development. Based on endogenous economic growth theory, we build a modified endogenous growth model to determine the optimal rates of economic growth, environmental pollution, energy input, and other factors in the context of co-benefits. Further empirical analysis is given which is missing in previous studies in this field. The empirical analysis reveals that China's actual GDP, consumption, energy input, and physical capital growth rates are much higher than the optimal growth rate. However, the human capital and environmental pollution control growth rates are slower than the optimal values. Although China has a rapid growth in economy, the optimal level of comprehensive co-benefits has not been reached yet.