生命周期评价方法研究综述——兼论混合生命周期评价的发展与应用

生命周期评价(Life cycle assessment,LCA)随着其评价对象不断复杂化、系统化,逐渐发展出包含基于清单分析的过程生命周期评价(Process-based LCA,PLCA)、投入产出的生命周期评价(Economic input-output LCA,EIO-LCA)和混合生命周期评价(Hybrid LCA,HLCA)三种方法。论文简述了各类LCA方法的发展过程和特征,并结合实例分析了各自的优势与不足。结果认为:自下而上的PLCA方法针对性较好,其评价结果较为详细,但由于主观边界设定,核算结果存在无法避免的截断误差;自上而下的EIO-LCA方法采用投入产出表进行评价,边界为整个国民经济系统,但存在部门聚合、数据滞后等问题;HLCA结合PLCA与EIO-LCA两种方法,既保持了结果的精准性,又消除了截断误差。研究最后总结并提出未来HLCA的发展方向,以期为LCA方法的进一步发展提供参考。

A Review on Hybrid Life Cycle Assessment: Development and Application

With the continuously strengthening complexity and systematization of its evaluation objects, life cycle assessment (LCA) methodology has gradually developed into three categories, including process based LCA (PLCA), economic input-output LCA (EIO-LCA) and hybrid LCA. The development and features of these methods were briefly stated in this study, and their strengths and weaknesses were analyzed with examples. It can be concluded that the bottom-up PLCA method, which is based on specific facility/site data, can describe elements in a supply chain precisely, but there exists cutoff error due to subjective boundary selection. The EIO-LCA method, which is based on national input-output table, is holistic but suffers from data lagging and aggregation error due to coarse graining of processes. The hybrid LCA has advantages of precision and completeness, since it combines PLCA and EIO-LCA. Then the paper emphasizes on discussing hybrid LCA. Some prospects of hybrid LCA were concluded and previewed to provide suggestions for its further improvement and development.