Outlining reasons to apply hybrid LCA—a reply to “rethinking system boundary in LCA” by Yi Yang (2017)

Excerpt

We appreciate the reply of Yang (2017a) to our letter (Gibon and Schaubroeck 2017). It became clear to us that Yang (2017b) does not mainly criticise the hybrid LCA method, but rather the misconception around the idea that hybrid LCA would lead for sure to higher accuracy if a more complete system boundary is obtained, as also well specified in another work of his (Yang et al. 2017). We agree that this is a misconception because of data and methodological restrictions. However, this does not mean that the method as such, from a conceptual point of view, should be solely criticised for general limitations in the linear framework and system boundaries in comparison to other linear LCA, what Yang (2017b) though appeared to do. This entails another discussion. Likewise, the discussion on rethinking system boundaries in his reply (Yang 2017a) seems to focus on the need (or intention) to have a flexible system boundary and a non-linear framework (which we frankly agree with), rather than on the hybrid LCA methodology itself, the original topic of discussion. …