A comparative Life Cycle Assessment and Life Cycle Costing of selected bio-based packaging materials in comparison with an LDPE film

This study presents a comprehensive Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) analysis of selected bio-based packaging materials, including cassava starch- and chitosan-based film and edible coating (NARO, UG), PPnc-based film (SUA, TZ), cassava starch- and coconut oil-based film (UoN, KE) and CNC-based film (INAT, TN), compared to conventional low-density polyethylene (LDPE) film packaging.
The environmental impact was assessed using the ReCiPe 2016 Midpoint method, analyzing 18 impact categories and using “the amount of bio-based packaging material required to package 1 kg of food from production to end-of-life disposal” as the functional unit. Diagrams were utilized to illustrate the carbon footprint of both bio-based and conventional materials, highlighting the contributions of specific unit operations. The analysis was conducted using SimaPro PhD software version 9.3.0.3 with the Ecoinvent version 3 database. Among bio-based materials, starch- and chitosan-based biofilm (NARO) emitted 1.87 kg CO₂ equivalent per kilogram, primarily due to electricity consumption (1.12 kg CO₂ equivalent) and acetic acid use (0.675 kg CO₂ equivalent). The starch- and chitosan-based biocoating (NARO) production resulted in 1.63 kg CO₂ equivalent
per kilogram, with electricity, acetic acid, and chitosan being the dominant contributors. PPnc-based film (SUA) exhibited 1.61 kg CO₂-eq/kg, with electricity and glycerol contributing significantly. CNC-based film (INAT) had the highest environmental load among bio-based materials, emitting 3.83 kg CO₂-eq/kg, primarily from transportation, polyester complexed starch, and cellulose nanocrystals. Conventional LDPE film had the highest impact, emitting 6.08 kg CO₂-eq/kg, driven by transportation, electricity and naphtha use.
While bio-based materials generally demonstrated lower environmental impacts, CNC-based biofilm approached the carbon footprint of LDPE, underscoring the need to optimize bio-based production processes. To enhance sustainability, producers of CNC-based films should focus on reducing energy consumption, optimizing supply chains and exploring alternative raw materials.
All the bio-based film prototypes were also analysed with Life Cycle Costing (LCC) analysis, focusing on direct production costs incurred in laboratory-scale innovation, and comparing them with LDPE conventional film.
Key cost parameters analysed included raw materials, labour, energy, water, transport, and production output in terms of the number and size of films/pouches produced. Data collection was facilitated using an automated Excel template to record detailed cost reporting. The cost of production was calculated based on the direct costs incurred per production process or batch. The analysis revealed significant cost disparities among the bio-based films and LDPE film. The total production costs reported were 28.36 (UoN), 53.49 (SUA), 58.76 (INAT), and 78.24 (NARO) (all in dollars), while the LDPE film had the lowest cost at 24.94. When factoring in the number of films produced (UoN: 907 films, INAT: 1113 films, NARO: 128 films, SUA: 20 films, and LDPE: 907 films), the cost per film varied significantly. LDPE achieved the lowest cost per film at 0.027, followed by UoN at 0.031 and INAT at $0.053. NARO and SUA had higher costs per film at 0.61 and 2.675, respectively (all in dollars).
Since the films varied in size, a simple cost-per-film analysis was insufficient for a fair comparison. After normalizing costs per the size, INAT had the lowest cost at 0.0440 /500 cm², followed by LDPE at 0.1636 /500 cm² and UoN at 0.1861 /500 cm². However, NARO and SUA continued to exhibit high costs of 1.5918 and 1.6715 /500 cm², respectively. In terms of least-cost pricing, INAT and UoN bio-based films are better positioned to compete with conventional LDPE films due to their lower costs. Conversely, the high production costs reported by SUA and NARO pose significant challenges for market entry and competitiveness.

Despite the increasing demand for sustainable alternatives to conventional packaging, challenges related to production costs remain a major barrier to the widespread adoption of bio-based films. The findings highlight significant cost disparities across various production parameters and emphasize the need to scale production to achieve economies of scale, as these materials are currently produced at a laboratory or semi-pilot scale. Addressing these cost-related challenges will be crucial for the broader promotion and adoption of bio-based packaging solutions in the market.