– by Isabella Drury, a contributing writer.
As you stand in line at your favorite coffee shop, you face a familiar dilemma: should you opt for a disposable cup or grab a reusable one? This everyday choice may seem insignificant, but it reflects a growing concern about sustainability and the impact of manufacturing on the environment.
One key aspect of sustainability is the carbon footprint, which measures the total greenhouse gas emissions caused by an individual, event, organization, or product. However, to truly understand the environmental impact of our choices, it’s crucial to consider the entire life cycle of a product, from production to disposal.
This is where life cycle assessment (LCA) comes into play. LCA is a method for evaluating the environmental impact of a product or service throughout its entire life cycle. This includes raw material extraction, manufacturing, transportation, use, and end-of-life disposal.
In this article, we’ll use product footprinting software based on LCA methodology, Ecochain Mobius, to compare the sustainability of reusable and disposable coffee cups. Examining their carbon footprints, resource consumption, and waste generation. By considering the full life cycle of these products, we can make more informed decisions about our manufacturing choices and their impact on the environment.
Reusable coffee cup
Reusable coffee cups are typically made from durable materials such as stainless steel, plastic (like BPA-free polypropylene), glass, or bamboo. These materials are chosen for their longevity and ability to withstand daily use, with certain materials–steel–being used to keep drinks hot for long periods of time.
You only need to buy it once and you can use it for life–or until you lose it. However, the production of these cups has an environmental impact, to varying degrees. Manufacturing stainless steel requires mining, refining, and processing, which consumes energy and resources. Plastic cups are derived from petroleum, and their production also involves energy consumption and potential pollution. And glass cups, while recyclable, require energy to produce and transport because of their weight.
Regularly using a reusable cup can significantly decrease an individual’s contribution to waste and help minimize the environmental impact associated with single-use cups. Emphasis on regularly, as these mugs have to be used a certain amount of times to offset the emissions of manufacturing, taking between 20 to 100 uses to become truly sustainable.
It’s also important to consider the end-of-life disposal options. Stainless steel cups can be recycled as scrap metal, while plastic cups can only be recycled if facilities accept the specific type of plastic. The cup’s inbuilt longevity reduces the need for frequent replacements and minimizes the overall environmental impact.
Disposable cup
Disposable coffee cups are typically made from paper with a thin plastic lining, which helps prevent liquid from soaking through the cup. The production of these cups involves harvesting trees for paper pulp, processing the pulp, and applying the plastic lining.
The manufacturing process of these cups consumes energy, water, and chemicals, and the extraction and processing of raw materials contribute to the overall environmental impact of disposable cups.
Disposable coffee cups are designed for single use, meaning they are used once and then discarded. This convenience is a major factor in their widespread use, as they can be easily disposed of after use. However, this convenience comes at a cost to the environment, as the frequent use of disposable cups leads to a substantial accumulation of waste, with half a trillion single-use cups being manufactured each year. The short lifespan of these cups, often mere minutes, stands in stark contrast to the long-term environmental consequences of their disposal. Discarding disposable coffee cups also presents significant challenges. While the paper portion of the cup is theoretically recyclable, the plastic lining makes the recycling process more difficult and expensive. Most recycling facilities lack the equipment to separate the paper from the plastic, resulting in the majority of disposable cups ending up in landfills or incineration.
In landfills, the cups can take decades to decompose, contributing to the accumulation of waste and the release of greenhouse gasses such as methane. In the incinerator, burning may emit toxins and pollutants.
How to compare the environmental impact of two products
Let’s look at a breakdown of the environmental impact of a traditional disposable coffee cup and a stainless steel coffee cup to understand how we could go about comparing the two products.
You want to begin by gathering the bill of materials for the products you’re comparing. This is a list of the raw materials, sub-assemblies, sub-components, and the quantities of each needed to manufacture your end product.
You can use Large Language Models (LLMs) such as ChatGPT or Claude to assist in gathering and organizing this information. These AI tools can help extract relevant details from product specifications, technical documents, and industry databases. However, it’s important to note that while LLMs can greatly speed up the process, the information they provide may not be 100% accurate. This approach is more suitable for initial comparisons, general understanding, and identifying areas that require further expert verification.
Once you have gathered your product data, you enter it into your product footprinting software to get a model of its impact. We have used Ecochain Mobius to model the product’s impact and generate our comparison.
In Ecochain Mobius, you can use the comparison feature to compare the impact model of two different products. Here we have compared these two coffee cups, and you can see the total CO2 emissions of each product.
Please note these comparisons are based on a fictional model.
Initially, it may look like the disposable coffee cup is the more environmentally friendly option, as the stainless steel cup has 0.98 kilograms more carbon emissions, a whopping 92.5% increase. Except, we have to take into account that disposable coffee cups are only used once, whereas stainless steel cups can, theoretically, last a lifetime.
To get a comprehensive overview of a product’s impact, it is vital to assess the environmental footprint across the entire life cycle of the product.
For simplicity, let’s compare these two cups over one year of use. If you treated yourself to one takeout coffee per week–that’s 52 uses. For the stainless steel cup, we’ve also included a 10km tram trip you might’ve taken when purchasing the item, and the need to wash it each time you use it.
Using this model, we can begin to see a product’s true impact. After a year’s usage, the disposable coffee cup now emits 4.8kg of CO2 equivalent per year, whereas a stainless steel cup only emits 2.24kg of CO2 equivalent per year–and this impact will not substantially grow the more you use it.
This comparison reveals the complexity of product sustainability. What seems eco-friendly at first glance may not be when considering a product’s entire life cycle. To make truly informed decisions about sustainability in manufacturing and consumption, we need robust tools for accurate analysis.
– product footprinting software based on LCA methodology, like Ecochain Mobius offer a powerful solution for conducting life cycle assessments, enabling businesses like yours to compare products effectively and make choices that genuinely reduce environmental impact.