Comparative life cycle GHG emissions of single-use plastic cups and reusable cups for beverages

Single-use plastic (SUP) products are widely used due to their convenience and low cost, with SUP cups being particularly prevalent in coffee shops and fast-food restaurants. This study estimates SUP cup consumption and evaluates their environmental impacts, focusing on global warming, through a cradle-to-grave life cycle assessment (LCA). Five scenarios (S1-S5) were set and compared with conventional SUP cups. Results indicate that 5.8 billion SUP cups were consumed in coffee shops and fast-food restaurants in South Korea in 2022, equating to 113 cups per person annually. The global warming potential (GWP) for the baseline scenario (S1) was 8.12 kgCO2eq per functional unit, with SUP polymer production being the largest contributor. Scenario 5 (S5), involving a 25% substitution with reusable plastic cups and tumblers, achieved a 20% GWP reduction compared to S1. However, increased raw material use, energy demands, and cleaning processes for reusable cups led to higher burdens on land use and mineral extraction. It was found that reuse rate of reusable cups significantly influenced the results. This study highlights the effectiveness of deposit return scheme (DRS) and reusable cup policies, providing essential data to guide regulatory measures that mitigate SUP cup impacts and promote sustainable alternatives.