Assessment of the environmental break-even point for deposit return systems through an LCA analysis of single-use and reusable cups

The Circular Economy introduced new research challenges to be faced. Linear and circular supply chain comparisons require general methodologies to obtain significant and scalable results. A two-step methodology is here proposed to facilitate the interpretation of results during a Life Cycle Assessment (LCA). Firstly, an LCA analysis has been conducted on four single-use - Polypropylene (PP), Polylactic acid (PLA), Polyethylene terephthalate (PET), and Cardboard+Polyethylene coat - and reusable - PP, PLA, PET, and glass - cups. Secondly, the analyzed midpoint impact categories have been aggregated into the three main life cycle phases: production, use and End of Life (EoL). Then, they have been used to assess the environmental break-even point (BEP), i.e. the minimum number of uses necessary for a reusable cup to be preferable than a single-use cup, considering two EoL (energy recovery, and recycling) and three use phase strategies (onsite handwashing, onsite and offsite washing). Considering offsite washing - transport distance of 20km and industrial washing machines - and energy recovery, findings highlight that reusable plastic cups reach a break-even point for climate change and non-renewable energy use for n < 150, while single-use PP cups are the best option in terms of acidification, eutrophication, and water scarcity indicator. With respect to PP single-use cups, for acidification, eutrophication, and water scarcity indicator, a BEP cannot be achieved, even in the case of infinite reuses. Results evidenced all the conditions for reaching a BEP, allowing to identify possible strategies to improve the efficiency of reusable products and to obtain an environmental benefit. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.