最终需求的完全碳排放强度变动及其影响因素分析

Analysis of the Change of Complete Carbon Intensity and Its Determinants from the Perspective of Final Demand

区别于传统视角的碳排放强度研究,本文从供给和需求,产出和增加值的内在联系出发,提出了最终需求视角下的完全碳排放强度及其消费的完全碳排放强度、投资的完全碳排放强度和出口的完全碳排放强度相关概念和计算方法,并根据合并WIOD形成的1996-2009年的中国非竞争型投入产出表完成了对各类完全碳排放强度的测算,以及对完全碳排放强度的变动的直接贡献率分解,同时对各类完全碳排放强度的变动进行了直接碳排放系数效应、中间投入技术结构效应、增加值系数效应和最终需求规模效应4种驱动因素的SDA分解。结果显示:第一,期间消费的完全碳排放强度均小于投资和出口的完全碳排放强度,且消费的完全碳排放强度对完全碳排放强度变动的直接贡献率要大于投资和出口,表明消费中隐含的碳排放与增加值的比例沿着"集约型"路径不断优化,而出口和投资的增长路径则相对"粗放"。第二,各类完全碳排放强度的减排路径大体一致,直接碳排放系数效应为正,而中间投入技术结构效应、增加值系数效应和最终需求规模效应均为负,暗含投入产出结构、各类需求的隐含增加值系数以及规模变动对碳排放强度下降并没有起到积极作用,而主要源泉还是直接碳排放系数下降。其中直接碳排放系数、中间产品技术结构效应和增加值系数效应的变化在投资的完全碳排放强度中作用较大,而最终需求规模的变化在消费的完全碳排放强度中作用较大。第三,各类完全碳排放强度变化以及其背后的驱动力具有明显的分阶段特征。2002-2004年投资和出口的完全碳排放强度变化促使了完全碳排放强度上升,而2004-2009年则对完全碳排放强度的下降有一定的正贡献。入世以前增加值系数对各类需求的完全碳排放强度下降的贡献为正,而其后贡献为负。其中,在2003-2007年投资和出口的完全碳排放强度变化中表现更为明显。因此,降低碳排放强度是一项系统工程,减排技术仍是最直接和有效的措施,而需求模式调整也是降低碳排放强度的重要手段之一,特别是降低出口和投资的中隐含碳和提高出口和投资中的增加值率,同时也要警惕消费结构变动中如汽车等高能耗产品普及带来的不利影响。

Different from former researches on carbon intensity, based on the links between supply and demand as well as that between output and value added, firstly this paper proposes such concepts as complete carbon intensity （CI） and its consumption-oriented complete carbon intensity （CCI）, investment-oriented complete carbon intensity （ICI） and export-oriented complete carbon intensity （XC1） from the perspective of final demand. By using Chinese non-competitive input-output model during 1996 -2009 merged from World Input-Output Database （ WIOD）, this paper then estimates all kinds of complete carbon intensities and decomposes the change rate of complete carbon intensity. Meanwhile, we use structural decomposition analysis （SDA） to decompose changes of all kinds of complete carbon intensities into four factors： direct carbon emission coefficient effect, input technology structure effect, value added coefficient effect and scale effect of final demand. The results are as follows： ① From 1996 to 2009, consumption-oriented complete carbon intensity is the lowest, and it has the greatest impact on complete carbon intensity （ CI）, which indicates the proportions of carbon emissions to value added embodied in consumption products is gradually optimized along the ＂intensive＂ path, while the growth modes of export and investment are relatively ＇extensive＇ ②Different complete carbon intensities are reduced almost in the same way. The coefficient of direct carbon emission is positive while the coefficient of input technology structure, value-added coefficient and final demand are negative. It indicates that direct carbon emission coefficient is the main source of carbon intensity reduction, in which other factors do not play active roles. In particular, the fluctuation of investment-oriented complete carbon intensity （ICI） is mainly influenced by fluctuation of direct carbon emission, input technology structure and value-added. On the contrary, changes in the scale of final demand impact consumption-oriented complete carbon intensity （CCI） greatly. ③Various complete carbon intensities and their driving forces change in different time intervals. Fluctuation of investment-oriented complete carbon intensity （ICI） and export-oriented complete carbon intensity （CCI） contribute to the growth of complete carbon intensity （CI） during 2002 - 2004 but promote the decrease of complete carbon intensity （CI） during 2004 -2009. Before China＇ s entry into WTO, changes in value-added coefficient positively affect the decline of all final demands ＇ complete carbon intensities, but their effects turn to negative afterwards. Such phenomenon is mostly apparent for the changes in investment-oriented complete carbon intensity （ICI） and export-oriented complete carbon intensity （ECI） from 2003 to 2007. In conclusion, reducing complete carbon intensity is a systematic project that calls for measures from all aspects. Carbon emission reduction technology is still the most direct and efficient measure, while re-adjusting demand structure is also a key point. It is necessary to reduce the carbon emissions embodied in export and investment while improve the value added rate in them. Nevertheless, we should also be vigilant about the adverse effects of changes in consumption structure, for example the popularity of high energy consumption products like cars.