In the United States, although recycling systems and bottle deposits are more common, the rates of actual recycling for polyethylene terephthalate (PET) bottles are shockingly low, as confirmed by MIT researchers. However, their research provides potential solutions for improvement.
Currently, the national recycling rate for PET bottles stands at around 24%, and there has not been any significant change for a decade, as per the researchers. Yet, their findings suggest that implementing a nationwide bottle deposit program could increase recycling rates to 82%, with nearly two-thirds of PET bottles being recycled into new ones at a cost of just a penny per bottle when the demand is high.
This program could be a game changer for the environment, but it would require policies to ensure a sustainable demand for recycled material.
The team conducted an in-depth analysis of PET bottle collection and recycling rates in various regions, comparing the impact of bottle deposit policies and curbside recycling programs. Their findings highlight the significant effectiveness of bottle deposit programs yet also reveal a shortfall in meeting industry targets for bottle collection. The study suggests that implementing a uniform nationwide bottle deposit policy could align with legislative mandates and corporate sustainability goals.
Furthermore, the study emphasizes the high success rate of PET recycling in terms of material quality, with products made from all-recycled material rivaling virgin material in quality. Brands have demonstrated the feasibility of producing new bottles using 100% post-consumer waste.
However, the limited collection of PET material poses a critical challenge for processing plants in meeting their operational requirements. Nonetheless, the researchers believe that with appropriate policies in place, a positive outlook is attainable.
“A message that we have found in a number of cases in the recycling space is that if you do the right work to support policies that think about both the demand and also the supply,” then significant improvements are possible, she says. “You have to think about the response and the behavior of multiple actors in the system holistically to be viable,” she says. “We are optimistic, but there are many ways to be pessimistic if we’re not thinking about that in a holistic way.”
The study emphasizes the importance of taking into account the needs of existing municipal waste-recovery facilities. While expanded bottle deposit programs are crucial for boosting recycling rates and supplying companies with the materials to recycle PET into new products, it’s crucial to recognize that current facilities processing material from curbside recycling programs will experience a loss in revenue from PET bottles. These bottles, being a relatively high-value product compared to other materials in the recycled waste stream, are a significant source of income for these facilities. Without the revenue from PET bottles, these facilities would be left with only the lower-value mixed plastics.
The researchers constructed economic models based on collection rates in states with deposit programs, recycled-content requirements, and other policies. They used these models to project the impact at a national level.
Overall, they determined that a nationwide bottle deposit system with a 10-cent deposit per bottle could meet the supply needs of packaging producers at a net cost of about 1 cent per bottle produced, particularly when there is strong demand. Instead of being a federal program, the implementation of such a system is proposed to be left to the individual states, according to Olivetti.
Other countries have achieved remarkable success with deposit systems, boasting participation rates of over 90% for PET bottle recycling. In contrast, the U.S. only manages to collect less than 29% of PET bottles for recycling, with approximately 24% ending up actually recycled after losses in the recycling chain. It’s noteworthy that despite 73% of Americans having access to curbside recycling, only 10 states have implemented bottle deposit systems.
When it comes to recycling, it’s important to consider the entire cycle of supply and demand and the various players involved. Policies should not only aim to increase recycling rates but also address the need for cleaner and more economical recycling processes.
To ensure the effectiveness of such policies, safeguards must be in place to protect existing recycling facilities from potential revenue losses resulting from bottle deposits. One possible solution could involve providing subsidies funded by fees on bottle producers. It’s also crucial to implement other policies, such as recycled content requirements and extended producer responsibility regulations, to maintain the market for the collected material.
“When we start to think about mixed plastic streams, that’s much more challenging from an environmental perspective,” she says. “Recycling systems need to be pursuing extended producers’ responsibility, or specifically thinking about materials designed more effectively toward recycled content,” she says.
It’s also important to address “what the right metrics are to design for sustainably managed materials streams,” she says. “It could be energy use, could be circularity [for example, making old bottles into new bottles], could be around waste reduction, and making sure those are all aligned. That’s another kind of policy coordination that’s needed.”
Journal reference:
- R. Basuhi, Karan Bhuwalka, Richard Roth, Elsa A. Olivetti. Evaluating strategies to increase PET bottle recycling in the United States. Journal of Industrial Ecology, 2024; DOI: 10.1111/jiec.13496