Can aluminum cans replace plastic bottles?

Aluminum cans and plastic bottles of Coca-Cola share shelf space in a grocery store. Why do we need both types of containers? Image credit: Yahoo Finance

The future explosion of the plastic packaging industry was revealed at the 1963 National Plastics Conference. In a paper by Lloyd Stouffer, Plastic Packaging: Today and Tomorrow, Stouffer visualizes the never-ending economic bounty that would result from disposable plastics, since each instance of disposable packaging would have to be replaced. The lead paragraph says it all, “The future of plastics is in the trash can.”

As you can see from a standard grocery store beverage display in the image above, there is a mix of plastic bottles and aluminum cans, both containing the same beverage. Aluminum is valuable and has a high recycling rate worldwide. The supply chain for the production of aluminum cans is already in place for many brands and products. Why not reduce the plastic supply chain for beverages and expand the aluminum supply chain? The impacts would be far-reaching.

Statista estimated that 583.3 billion plastic bottles were produced in 2021. According to Bloomberg Green, “each year, beverage companies in the U.S. produce about 100 billion of these plastic bottles to sell their soda, water, energy drinks, and juices. Globally, Coca-Cola Co. alone churned out 125 billion plastic bottles last year (2021) –about 4,000 each second.”

What about aluminum cans? According to The World Counts website, aluminum cans are the largest use of aluminum globally. The Coca-Cola Company is reportedly the biggest user of aluminum cans in the world. The firm uses over 300,000 tons of aluminum sheets each year to make 112.5 billion cans across its various beverage brands. Anheuser-Busch InBev used over 20 billion cans in 2021, and PepsiCo uses more than 10 billion aluminum cans annually.

Ball Corporation is widely regarded as the largest manufacturer of aluminum cans in the U.S., reportedly manufacturing over 50 billion recyclable beverage cans a year, and their latest plant in Peru alone will have a production capacity of over 1 billion cans a year.

Recycling rates: aluminum vs. plastic

GreenBiz called the aluminum can “America’s most successful recycling story that you’ve never heard.” In 2019, they reported a recycling rate of nearly 50%, “the highest recycling rate for any beverage container in the U.S.” According to Statista, “the average recycling rate for aluminum beverage cans in the European Union, UK, Switzerland, Norway, and Iceland was 72.8 percent in 2020 with Germany and Finland coming in at 99 and 98 percent, respectively.”

PET bottle recycling has been more of a challenge. While Norway, Lithuania, and India, have achieved recycling rates exceeding 90% for plastic bottles (PET), Bloomberg Green reports that “just 26.6% of PET bottles were recycled in the US in 2020. The rest were incinerated, stuffed into landfills, or tossed aside as litter,” according to the National Association for PET Container Resources (NAPCOR). In Miami-Dade, Florida’s most-populated county, the Florida Department of Environmental Protection reported that only one in 100 plastic bottles is recycled.

Low plastic recycling rates in the U.S. have resulted in a shortage of recycled PET plastic. Until dozens of new plants are built, enough raw material will not be available to create a more circular plastic supply chain, according to Evergreen Recycling. PET plastic is limited in how many times it can be recycled and degrades over time, while aluminum can be recycled an infinite number of times and maintain its integrity.

Obstacles to using aluminum instead of plastic

Aluminum's high level of circularity makes aluminum cans a more sustainable choice, and expansive supply chains are in place for both aluminum and plastic. So why doesn’t the beverage industry use the more sustainable aluminum exclusively?

• Cost: Aluminum cans are generally more expensive to produce than plastic bottles.
• Customer preference: Some customers prefer the taste, feel, and look of plastic bottles over aluminum cans.
• Variety of sizes: Plastic bottles come in a wide range of sizes. From small single-serving bottles to large 2-liter bottles, which can be more convenient for certain occasions. Aluminum cans are usually limited to a few standard sizes.
• Packaging Design and Marketing: Beverage producers may choose packaging materials that align with their brand image and marketing strategies.
• Production speed: Plastic bottles are generally easier and faster to produce than aluminum cans.
• Product Compatibility: Some beverages, especially those with specific pH levels or properties, may not be suitable for aluminum cans due to potential reactions between the beverage and the metal.
• Weight and Transportation: Aluminum cans are lighter than glass bottles and have certain advantages in terms of transportation costs. Plastic bottles can be even lighter than aluminum cans, potentially reducing transportation expenses further.
• Supply Chain Considerations: Availability of materials, manufacturing capabilities, and supply chain logistics can impact the choice of packaging materials.

This graphic from The Aluminum Association compares circularity data for aluminum cans, glass bottles, and plastic bottles (PET), including the value of each material. Image credit: The Aluminum Association

Does the cost of EPR make aluminum a cheaper choice?

While plastic bottles are cheaper to produce than aluminum cans, that cost savings does not account for the environmental cost of plastic pollution. If the cost of extended producer responsibility (EPR) and the cost of other unintended environmental consequences of plastic bottles are added, the real cost of aluminum cans is likely less.

Further, brands do not ask customers if their preferences would change if they had a more sustainable choice (aluminum cans) instead of plastic bottles. A large percentage of consumers would likely say yes, particularly if the brand owners publicized the sustainability importance of the shift to aluminum cans. Novelis Inc., a leading sustainable aluminum solutions provider, said last year that the firm “expects demand for aluminum beverage can sheet to grow at a 3% compounded annual growth rate from 2022 to 2031. The demand growth is driven by consumer preference for more sustainable products and size variety, as well as more beverage types being packed in cans, including water, energy drinks, soda, beer, wine, hard seltzers, and ready-to-drink cocktails.”

Are customers willing to keep polluting the ocean with plastic bottles because they like the taste, feel, and look of plastic bottles more than aluminum? Do customers even know they are doing that?

While supply chain considerations are often overlooked when addressing environmental issues, they are important, particularly for multinational corporations trying to make cost-effective business decisions in different regulatory environments. Aluminum cans are ubiquitous in almost every country in the world, so expanding the existing aluminum supply chains is achievable.

Given the above, shouldn’t transitioning from plastic bottles to aluminum cans be considered an important part of the solution to plastic pollution?