自愿减排项目碳泄漏：内涵、类别及应对

自愿减排项目是碳排放交易市场抵消机制的运行载体,灵活的自愿减排抵消机制是碳排放交易市场的补充,对应对全球气候变化问题具有重要意义。碳泄漏,作为严重影响抵消项目减排效率的热点问题值得关注。目前,中国已形成较大规模的自愿减排市场,截至2018年底,国家发展改革委共签发了约7200万tCO_2当量减排量,我国在建立健全自愿减排抵消市场机制的过程中,需要把握项目碳泄漏的负外部性这一实质,厘清其运行机理并积极应对。本文旨在系统阐述该问题,并为进一步实现抵消项目减排潜力提供思路和方向:从自愿减排项目碳泄漏的内涵与定义出发,首先对项目碳泄漏的分类进行梳理,并依据产生途径的不同重点分析了活动转移排放、生命周期、市场路径、生态以及技术泄漏的作用机制、影响因素及其相应的研究方法;其次从具体项目应用、系统项目应用和宏观应用三个层面讨论了应对自愿减排项目碳泄漏问题的管理对策;最后结合我国自愿减排抵消市场的实际情况,建议未来抵消项目碳泄漏的应对和管理应在分门别类对其概念进行精准定义的基础上将解决措施的成本效益考虑在内,此外,在评估泄漏量时需要同时测算不同类型的碳泄漏,探究其协同效应以免高估其泄漏程度。

Carbon Leakage for Voluntary Emission Reduction Projects: Concept, Classification and Measures

Voluntary emission reduction project is the operation carrier of the offset mechanism of carbon emission trading market. Certified emission reduction project can be used to offset part of the emission reduction obligations. The flexible offset mechanism is the supplement of carbon emission trading market, which is of great significance to deal with the global climate change issue. With the expansion of both international and regional offset market, carbon leakage, a hot issue that seriously affecting the reduction efficiency of offset projects, deserves attention. For project perspective, carbon leakage means an unanticipated increase or decrease in greenhouse gas benefits outside of the project''s accounting boundary as a result of the project activities. According to its different ways of occurrence, the issue can be divided into five types: activity transfer leakage, life cycle leakage, ecological leakage, market induced leakage and technological ones. The first three types also called first level or direct leakage, and the last two ones also named second level or indirect leakage. Qualitative and quantitative methods are two ways to analyze the leakage issue. Qualitative ones mainly investigate the influencing factors of carbon leakage and determine whether a project has the leakage risk. Quantitative methods need modeling, constructors or econometrics. As for ways to deal with the issue, they are classified into three types according to the application scope: specific project level, system project level and macro level measures. Today, China has formed a large-scale voluntary emission reduction market. By the end of 2018, the National Development and Reform Commission had issued around 72 million tons of CO₂ equivalent emission reduction of the voluntary projects. In the process of establishing and improving the voluntary emission reduction market, it is necessary to recognize the negative externality essence of project perspective carbon leakage, clarify its operation mechanism and take actively responses to it. Moreover, in the future research of the issue, a precise definition of the concept is a basis, then the cost-effectiveness of dealing measures should be taken into consideration. At the same time, when estimating the leakage rate, simultaneously calculate different types of carbon leakage to explore the synergistic effect is suggested, so as to avoid overestimation.