What is life cycle assessment (LCA)?
Let’s think about evaluating the environmental impacts of a human-made physical product—a coffee pod, what comes to mind may be only associated with the production and manufacturing or consumer use stage. In contrast, life cycle assessment (LCA) assesses the environmental impacts from all the stages across the coffee pod's life, including all the upstream activities before the product becomes waste. Thus, the life cycle would start from the agricultural stage where coffee beans are farmed, through the production of packaging materials, coffee beans roasting, production of coffee pods, transporting pods to the distribution center, and finally arriving at our home kitchen to supply coffee (Figure 1). The end of a pod’s life is the disposal of a used coffee pod.
The general purpose of an LCA is to provide a comprehensive view of emissions and environmental burdens of relevance when guiding environmental management for a product, service, and strategy or policy system. LCA quantifies all relevant emissions, resources consumed, and a broad range of burdens that represent the damage to the ecosystem, human health, and resource depletion associated with any processes in a system (product, service, policy, or strategy) and the system as a whole.
It is important to note that LCA does not quantify a specific single product from a region or company or the right one at your hand nor evaluate the exact impacts of the product due to the challenges of modeling and data availability. Furthermore, the goal of an LCA is to assess the potential emissions and environmental impacts of the system (e.g., coffee capsules + coffee makers). This system can be subject to a regional or national market (e.g., Switzerland, France, a U.S. University) where an average electricity mix, an average traveling distance between factory and distribution center, the fertilizer and land use for coffee beans farming can be consistently estimated.[1,2,3] The LCA can definitely source from a different market and consume more or less renewable electricity. The coffee cultivation methods, coffee bean types, and roasting levels could also vary and thus result in more or less environmental burdens. However, LCA allows drawing consistent and useful conclusions on the hotspot processes and the comparative performance among multiple scenarios (e.g., different primary coffee capsule packaging, other coffee systems like drip filter and full automat), as long as the goal and scope are consistently defined.
LCA is not merely applied to a product system but can also be applied to waste management service, also called waste LCA. Unlike the product LCA, waste LCA assumes zero burdens from the upstream activities before the end-of-life phase (Figure 2). Product LCA allows analysts to identify the critical processes that contribute the most to the environmental burdens and exert the largest potential for product improvement, while waste LCA allows determining the optimal strategy of how to manage a discarded product. Even though waste minimization and prevention through source reduction and reuse should be the top hierarchical waste management strategy, waste LCA assumes waste has been generated and entered the system to be treated and disposed. The waste management system is in itself complex due to various types of waste components, composite fractions, and different likely destined treatment and disposal strategies (e.g., recycling, composting, incineration, landfilling). To investigate the life-cycle processes and the relevant emissions and impacts, waste LCA looks at the waste collection, transportation to treatment sites, and inside waste treatment facilities and disposal sites (Figure 2).
What does an LCA do? (Spoiler Alert: Application Context Matters in LCA Design)
Before carrying out an LCA, a decision should be made on what this LCA is to be applied for at the early design and planning phase. An LCA can be applied in several decision context, including product development and improvement, strategy planning, public policy making, and marketing. The application context directly influences the way the LCA is designed, the methodological choices are made conduct the LCA (e.g., attributional or consequential modeling framework), and the results are communicated (e.g., eco-labelling, product sales, and incorporate social responsibility claim).
Reference
[1] Quantis. Life Cycle Assessment (LCA) of A Lungo Cup of Coffee Made from A Nespresso Original Capsule Compared with Other Coffee Systems in Switzerland; 2020. https://www.nestle-nespresso.com/sites/site.prod.nestle-nespresso.com/files/Nespresso LCA Executive Summary Quantis 2020-02-25(1).pdf
[2] Dubois, C.; Humbert, S.; Margni, M. Comparative Full Life Cycle Assessment of B2C Cup of Espresso Made Using a Packaging and Distribution System from Nespresso Espresso and Three Generic Products; 2011. https://cloud.cross-systems.ch/w/nespresso/corporate_assets/Quantis - Comparative LCA on Four Capsules Systems 2011.pdf
[3] Kooduvalli, K.; Vaidya, U. K.; Ozcan, S. Life Cycle Assessment of Compostable Coffee Pods: A US University Based Case Study. Sci. Rep. 2020, 10 (1), 1–24. https://doi.org/10.1038/s41598-020-65058-1.