“双碳”目标下政府补贴、需求替代与减排效应——来自中国乘用车市场的证据

Government Subsidies,Demand Substitution and Emission Reduction Effects under the Dual Carbon Target:Evidence from China’s Passenger Car Market

本文基于中国乘用车市场微观数据,应用结构估计方法,结合汽车需求替代和发电结构评价新能源汽车补贴政策的减排净效应,并模拟“双碳”目标下的减排效果。研究发现,新能源汽车购车补贴较好实现了市场推广的政策目标,贡献了新能源汽车销量的48.72%,但其中仅31.72%的增量来自对燃油车的替代,其余68.28%则来自补贴刺激的额外新增;补贴在减排方面存在双向作用,替代效应通过替代燃油车减少了尾气排放,直接效应刺激了新能源汽车额外新增,增加了用电排放,由于替代效应弱于直接效应,在当前发电结构下最终导致21个样本省市碳排放净增加941.39万吨,可见补贴并不是一项有效的减排政策。同时,补贴政策的减排效果与发电结构密切相关,发电结构达到“碳中和”时补贴政策会净减排1000.05万吨。基于此,本文提出,汽车行业减排的政策设计应关注需求替代与能源背景,适应能源结构调整的同时促进新能源汽车有效替代燃油车,以推进“双碳”目标的实现。

New energy vehicles provide a new channel for emissions reduction in the automotive industry,and their emission reduction effect depends on their efficiency as substitutes for conventional gasoline vehicles.Under subsidies,an increase in the sales of new energy vehicles can result from both the substitution of conventional vehicles and additional demand stimulated by the subsidies.New energy vehicles are not entirely emission-free—the carbon emissions generated during their usage phase are shifted to the electricity generation side.This leads to a dual effect of subsidies.On the one hand,the substitution effect of subsidies refers to the increase in sales of new energy vehicles achieved by substituting conventional vehicles,thereby reducing emissions from gasoline cars.On the other hand,the direct effect of subsidies means that the increase in sales of new energy vehicles is also driven by additional demand,where subsidies change consumers’decisions from not purchasing to purchasing new energy vehicles,resulting in additional emissions.Therefore,the emission reduction effect of subsidy policies depends on the relative size of these dual effects.Using microdata on the Chinese passenger vehicle market,this study employs structural estimation methods to disentangle the dual effects of subsidies.Combining automotive demand substitution and power generation structure,it evaluates the net emission reduction effect of subsidies for new energy vehicles and simulates the emission reduction effects under the dual carbon goals.The findings reveal that the purchase subsidies for new energy vehicles have effectively achieved the policy goal of market promotion,contributing to 48.72%of new energy vehicle sales.However,only 31.72%of this increment comes from the substitution effect on conventional vehicles,while the remaining 68.28%is attributed to the direct effect of subsidy stimulation.Subsidies have a two-way impact on emission reduction—the substitution effect reduces tailpipe emissions by replacing conventional vehicles,while the direct effect stimulates additional sales of new energy vehicles,increasing electricity-related emissions.Due to the weaker substitution effect compared to the direct effect,subsidies led to a net increase of 9.41 million tons of carbon emissions in 21 sampled provinces and cities under the current power generation structure,highlighting that subsidies are not an effective emission reduction policy.Furthermore,the emission reduction effect of subsidy policies is closely related to the power generation structure.When the power generation structure reaches“carbon peak,”it significantly reduces the negative externalities generated by subsidy policies,and when it reaches“carbon neutrality,”subsidy policies result in a net emission reduction of 10 million tons.Based on these findings,this study proposes three recommendations.First,the substitutability of new energy vehicles for conventional vehicles should not be underestimated.Promoting the substitution of new energy vehicles for conventional vehicles is a crucial pathway for emissions reduction in the automotive industry.Therefore,new energy vehicle policies should gradually shift from simply promoting the expansion of the new energy vehicle market to comprehensively enhancing the substitutability of new energy vehicles for conventional vehicles.Second,to achieve the dual carbon goals in the automotive industry,policymakers need to consider the alignment of policy design with the evolving power generation structure over time.Policy-driven substitution of new energy vehicles for conventional vehicles essentially involves energy substitution.With the advancement of the dual carbon goals,the gradual transition of the electricity structure toward cleaner and lower carbon emissions is an inevitable trend.Therefore,policy design in the automotive industry should align with adjustments in the power generation structure.Finally,the estimation results focus on the usage phase of automobiles,finding that emissions from new energy vehicles during other phases of their lifecycle are still higher than those from conventional vehicles.Therefore,efforts to reduce emissions from new energy vehicles should not only be limited to the zero-emission aspect during their usage phase but also prioritize addressing emissions produced during other phases of their lifecycle.