Hybrid life cycle inventory methods - A review

A variety of methods can be used to compile a life cycle inventory (LCI) as part of a life cycle assessment (LCA) study. Hybrid LCI methods attempt to address the limitations inherent in more traditional process and input-output (ID) LCI methods. This paper provides an overview of the different hybrid LCI methods currently in use in an attempt to provide greater clarity around how each method is applied and their specific strengths and weaknesses. A search of publications quoting the use of hybrid LCI was undertaken for the period from 2010 to 2015, identifying 97 peer-reviewed publications referencing the use of a hybrid LCI. In over one third of the literature analysed, authors only refer to their analysis as a hybrid LCI, without naming the actual method used, making it difficult to fully understand which method was used and any potential limitations. Based on the way in which the various hybrid methods are applied and their existing use, the authors propose a set of clear definitions for existing hybrid LCI methods. This assists in creating a better understanding of, and confidence in, applying hybrid LCI methods amongst LCA practitioners, potentially leading to a greater uptake of hybrid LCI. (C) 2017 Elsevier Ltd. All rights reserved.