Science & Technology, UK (Commonwealth Union) – The Earth’s atmosphere is a delicate balance of various gases, which play crucial roles in maintaining the planet’s temperature and overall climate. Among these gases, greenhouse gases (GHGs) have gained significant attention in recent years due to their role in global warming and climate change. Understanding the nature of greenhouse gases, their sources, and their impacts on our planet is essential to developing strategies for mitigating the effects of climate change.
Research from the University of Sheffield have demonstrated that replacing plastics with alternative materials may actually lead to increased GHG emissions. Dr. Fanran Meng, from the University of Sheffield, Department of Chemical and Biological Engineering, joined hands with researchers from the University of Cambridge and the KTH Royal Institute of Technology to examine the emissions associated with plastic products versus their alternatives.
Their study, published in the journal Environmental Science & Technology, analyzed various applications of plastics and their substitutes, such as packaging, construction, automotive, textiles, and consumer durables, which collectively represent a significant portion of the plastic usage across the world.
Contrary to expectations, the findings revealed that in 15 out of 16 applications studied, plastic products resulted in lower GHG emissions compared to their alternatives. This reduction ranged from 10 percent to as much as 90 percent across the product life cycle.
To assess environmental impacts, the researchers utilized a tool called life cycle assessment (LCA) to compare the environmental effects of different products. The study employed an LCA approach to evaluate GHG emissions that were linked with plastic products versus alternatives across various sectors.
Even when considering only direct life-cycle emissions, plastics outperformed alternatives in nine out of 14 applications. This superiority was driven by factors such as the lower energy intensity during production and the weight efficiency of plastics, which contributed to their reduced environmental impact compared to materials like glass or metal.
Moreover, plastics exhibited superiority in upstream processes, encompassing production and transport, in 10 out of 16 applications. This advantage stemmed from their lower energy intensity and lighter weight, underscoring the effectiveness of plastic materials in reducing emissions, as per the study.
“Not all alternative or recycled products are better for the environment than the products they replace. Environmental policymaking needs life cycle assessment guided decision-making to make sure that GHG emissions are not unintentionally increased through a shift to more emission-intensive alternative materials. Demand reduction, efficiency optimisation, lifetime extension and reuse/recycling are win–win strategies to reduce emissions effectively. Solely focusing on switching to alternative materials is not,” explained Dr Fanran Meng, Assistant Professor in Sustainable Chemical Engineering from the University of Sheffield.
The examination also uncovered the intricate web of indirect effects stemming from the surrounding systems of plastics, significantly impacting certain applications. Take scenarios like insulation and hybrid vehicle fuel tanks, where these secondary impacts overshadow the direct emissions of plastics, presenting a nuanced understanding of their environmental footprint.
Researchers of the study further indicated that moreover, plastic packaging plays a pivotal role in preserving food quality across diverse categories, curbing food spoilage and the resultant GHG emissions. This critical function underscores the unquantified environmental advantages of plastic packaging when contrasted with alternative materials.
The research findings indicate that optimizing plastic usage, prolonging product lifespans, increasing recycling rates, and improving waste collection systems could provide more effective strategies for mitigating emissions that are linked to plastic products.
Dr. Meng further indicated that the study underscores the significance of employing life cycle assessment tools to gain a comprehensive understanding of how plastics and their substitutes impact the environment. Additionally, it’s crucial not to underestimate the repercussions of plastics on marine ecosystems and the potential ramifications for human and ecological well-being. Dr. Meng also pointed out that we must weigh these factors when selecting materials for products, ensuring their suitability for intended purposes and facilitating the development of a sustainable plastics industry.
The research team suggests that future modeling endeavors should encompass reusable bioplastics, compostable materials, and biodegradable alternatives. These were omitted from our current study due to their limited market presence and insufficient data regarding reuse.
The findings of the study titled “Replacing Plastics with Alternatives Is Worse for Greenhouse Gas Emissions in Most Cases” are detailed in the journal Environmental Science & Technology.
