动态最优碳税、适度减排关注与经济绿色转型

Dynamic Optimal Carbon Tax,Appropriate Concern of Carbon Emission Reduction and the Green Transition of Economy

本文构建了一个包含碳税政策、能源要素、碳排放和产出的新古典经济增长模型,在引入环境公共支出与政府减排偏好的基础上重构政府目标函数,探讨最优碳税的决定机制与碳排放的动态变化。研究表明,实施动态碳税能够带来消费产出比的增长和碳排放总量的下降,有助于经济向消费驱动及绿色低碳转型。此外,本文还对两种不同减排关注度下的动态碳税情形进行了模拟,结果发现在应对碳减排问题上,政府最合理的态度是保持适度关注,此时实施动态碳税政策有助于经济发展向更高层次的均衡迈进;倘若对碳减排持过度关注态度,那么实施动态碳税政策则会产生“双刃剑”效应,在实现更高减排效率的同时也会对产出和消费产生强烈的“挤出效应”,令二者陷入“双重底部循环”。因此,政府保持适度的减排关注才是适应当下经济发展需要的占优选择,这不仅能够为实现“双碳”目标托底,更有助于经济系统向更高的消费、更高的产出以及更加合理的结构转型。

This paper integrates carbon tax policy,energy factor,carbon emission as well as real output into a neoclassical economic growth model,then reconstructs the objective function of government authority by introducing an endogenous environment public expenditure and a governmental carbon emission reduction preference into it,and finally makes a deep discussion on the optimal carbon tax as well as the optimal carbon emission path.The research shows that the implementation of dynamic carbon tax can bring about an increase of consumption output ratio and a decrease of total carbon emission,which is conducive to the transition of economy to a consumption-driven with low-carbon pattern.In addition,this paper also simulates two kinds of dynamic carbon tax path under different reduction concerns of carbon emission.We find that when implementing dynamic carbon tax,the most reasonable attitude of the government to deal with carbon emission reduction is to maintain moderate attention,which is benefit for the economic system to reach a higher equilibrium.If an excessive attention is paid to carbon emission reduction,the implementation of dynamic carbon tax policy will lead to a‘double-edged sword’effect.Although it may achieve a higher carbon emission reduction effect,it will also produce a strong‘crowding out effect’on output and consumption,making them fall into a‘double bottom cycle’.Therefore,maintaining a moderate reduction concern of carbon emission is the optimal choice to meet the needs of current economic development.It can not only provide a foundation for the realization of the‘carbon peaking’and‘carbon neutrality’goals,but also help the economic system transition to a higher consumption,higher output as well as a more reasonable structure.