Comparing polypropylene (PP) single-use cold coffee cups, like those used at Starbucks, to paper cups
We’ll evaluate their lifecycle impacts, focusing on environmental, practical, and economic aspects. This comparison draws on life cycle assessments (LCAs) and industry data, covering raw material extraction, production, use, and disposal for a 500-word analysis.
Raw Material Extraction
PP cups are made from propylene, derived from fossil fuels like petroleum or natural gas. Extraction involves drilling, which disrupts ecosystems and emits greenhouse gases (GHGs), with raw material production accounting for over 60% of PP’s climate impact. Paper cups, conversely, use wood pulp from trees, requiring logging that can lead to deforestation if not sourced sustainably. Sustainable forestry (e.g., FSC-certified) mitigates this, but pulping consumes significant water and energy, with estimates of 10-20 liters of water per kg of paper. Both materials have high upstream impacts, but PP’s fossil fuel reliance ties it to non-renewable resources, while paper can be renewable if managed responsibly.
Production
PP cup production involves melting PP pellets and injection molding, a process that uses electricity and emits about 1.7 Gt CO2e globally for plastics. Paper cups require pulping, bleaching, and coating with a plastic liner (often polyethylene) to prevent leaks, adding a plastic component that complicates recycling. LCAs show paper cups have a higher energy footprint in production—up to 2-3 times more than PP due to pulping and coating processes. However, PP’s non-renewable source gives it a higher global warming potential (GWP), with emissions around 0.1-0.2 kg CO2e per cup compared to paper’s 0.08-0.15 kg CO2e, depending on recycling.
Use Phase
Both PP and paper cups serve the same purpose at Starbucks: holding cold coffee for short-term use. PP cups are more durable, resisting condensation and maintaining structural integrity longer, which enhances user experience for iced drinks. Paper cups, often used for hot drinks but sometimes cold, are less sturdy and may require double-cupping or sleeves, increasing material use. Both are single-use, perpetuating waste, but PP’s clarity and strength make it preferable for cold beverages aesthetically and functionally.
End-of-Life and Disposal
Disposal is where both cups falter. PP is recyclable (resin code 5), but only about 1% is recycled in the U.S. due to limited infrastructure. Most end up in landfills, taking centuries to degrade and releasing microplastics. Paper cups are also recyclable, but the plastic liner complicates the process, with global recycling rates below 10%. In landfills, paper decomposes faster (months to years) but emits methane, a potent GHG. If littered, PP contributes more to microplastic pollution, while paper degrades less harmfully but still litters. Starbucks is piloting recyclable paper cups, but consumer behavior and infrastructure limit success.
Environmental and Practical Trade-offs
LCAs suggest PP cups have a slightly lower GWP when recycled, but paper cups can edge out if sourced sustainably and composted. Water use is higher for paper (15 m³ per unit vs. PP’s 5-10 m³), but PP’s non-renewable origin and microplastic risk are drawbacks. Cost-wise, paper cups are often cheaper to produce, but PP’s durability may reduce add-ons like sleeves. Starbucks’ shift toward 50% recycled content by 2030 applies to both, but reusable cups outperform either, cutting impacts by 80-90% after a few uses.
Conclusion
PP cups excel in durability and aesthetics for cold drinks but rely on fossil fuels and contribute to microplastic pollution. Paper cups, potentially more renewable, require more energy and water in production and face recycling hurdles. Both have significant environmental costs.
Life Cycle Assessment of Disposable Cups Link: https://www.sciencedirect.com/science/article/pii/S0959652618331848 Description: This study from Journal of Cleaner Production provides a detailed LCA comparing PP and paper cups, covering energy use, GHG emissions, and water consumption. It supports the comparison of production impacts and GWP (0.1-0.2 kg CO2e for PP vs. 0.08-0.15 kg CO2e for paper).
Plastic Production and Environmental Impact Link: https://www.oecd.org/environment/plastics/Plastics-pollution-2022-Policy-Highlights.pdf Description: This OECD report details the environmental footprint of plastics like PP, including the 1.7 Gt CO2e emissions from global plastic production. It’s relevant for understanding PP’s fossil fuel dependency and microplastic risks.
Recycling Challenges for Single-Use Cups Link: https://www.epa.gov/facts-and-figures-about-materials-waste-and-recycling/plastics-material-specific-data Description: The U.S. EPA provides data on low recycling rates for PP (around 1%) and challenges with paper cup recycling due to plastic liners, supporting the disposal section’s claims.
Starbucks Sustainability Initiatives Link: https://www.starbucks.com/responsibility/environment/recycling Description: Starbucks’ official page outlines their efforts to improve cup recyclability and target 50% recycled content by 2030, relevant to both PP and paper cup innovations and end-of-life management.