Simulation and Optimization of New Energy Vehicles Promotion Policy Strategies Considering Energy Saving, Carbon Reduction, and Consumers’ Willingness Based on System Dynamics

New energy vehicles are an important tool for the transition to clean energy and sustainable development. The Nudge Theory is introduced to construct a management model for energy conservation and carbon reduction in new energy vehicles. The model takes into account the strategy of reducing or exempting charging fees for new energy vehicles. Through dynamic simulation, we analyze the impact of considering the Nudge Theory and not considering the Nudge Theory on the energy-saving and carbon reduction effect of new energy vehicles. Through the analysis, it is found that (1) the energy-saving and carbon reduction management model is constructed by introducing the consumer reference effect to optimize the effect of the strategy of charging fee reduction for new energy vehicles, which further enhances the effect of energy saving and carbon reduction. (2) The consideration of the boosting strategy can increase the consumers’ willingness to purchase new energy vehicles, and the growth of new energy vehicles is more significant under the combined strategy compared with the baseline scenario. In the combined strategy, from the beginning of the simulation of Scenario 6 to the end of the simulation, new energy vehicles increased by 131.74%. (3) In terms of energy-saving and carbon reduction effects, Scenario 3 in the single strategy has the best effect, and Scenario 9 in the combined strategy has the best effect. Compared with the baseline scenario, the number of new energy vehicles increased by 253.03%, and carbon dioxide emissions decreased by 38.85%. Scenario 9 of the combined strategy can reach the peak of carbon emissions by 2030, and carbon dioxide emissions will decrease year by year.