Abstract
With the Public-Private Partnership (PPP) mode playing an increasingly important role in the investment of infrastructure, promoting the diffusion of low-carbon technology innovation in PPP projects not only helps to reduce the carbon emissions of infrastructure, but also plays an important demonstration role in the low-carbon transformation of construction industry. In order to clarify the evolutionary mechanism of low-carbon technology innovation diffusion among stakeholders under the unique payment mechanism of PPP projects in China, the paper builds two different evolutionary game models respectively under government payment mechanism and consumer payment mechanism based on evolutionary game theory. The evolutionary relationship between the choice of behavior strategies and the change of influencing factors under different payment mechanisms are analyzed by numerical simulation. It is found that under government payment mechanism, the regulation cost of government to promote low-carbon technology innovation and the punishment of the superior regulatory authority for non-regulation behavior are the important factors affecting government's behavioral strategies. The low-carbon technology innovation cost of social capital and the intensity of government subsidy and punishment are the main factors affecting social capital's behavioral strategies; Under consumer payment mechanism, consumer becomes the ultimate payer of low-carbon products, and the income they get from purchasing low-carbon products and the subsidy provided by the government become the main factors determining consumer's behavioral strategies. Finally, from the perspective of government, social capital and consumer, countermeasures and management implications are put forward to effectively promote the diffusion of low-carbon technology innovation under different payment mechanism in PPP projects.