How do government subsidies promote new energy vehicle diffusion in the complex network context? A three-stage evolutionary game model

In order to cope with the impact of current coronavirus disease 2019 (COVID-19), the continued extension of financial subsidy period for new energy vehicles at the national level is a strong measure to support the sustainable development of new energy vehicle (NEV) industry. This paper further explores the promotion impact of government subsidies on NEV diffusion, and establishes a three-stage evolutionary game model. Based on the actual application, the NEV diffusion process is simulated in four kinds of authoritative networks. Results show that: (1) in the scale-free network, the subsidy rate must be high enough to promote full NEV diffusion, and the larger the network scale, the higher the threshold of subsidy rate; (2) in the small-world network, the larger the network scale, the more beneficial it is for full NEV diffusion; (3) for the small-scale network, topological characteristics have little effect on NEV diffusion depth, and only affect the speed when NEV diffusion reaches the stable state; (4) for the large-scale network, NEV diffusion in the scale-free network is more sensitive to the subsidy rate than that in the small-world network; (5) network topologies influencing NEV diffusion can be divided into two priorities. Finally, relevant policy recommendations are presented.