The carbon footprint of aluminium cans made in North America dropped by nearly half over the last three decades, according to new comprehensive Life Cycle Assessment (LCA) by sustainability consultancy Sphera. 

The Life Cycle Assessment of North American Aluminum Cans found that greenhouse gas emissions for aluminium beverage can production has dropped by 43% since 1991 and 7% since 2012. 

Energy demand has declined by similar levels during this time period. These reductions have been driven largely by decreased carbon intensity of primary aluminium production in North America, lighter cans and more efficient manufacturing operations.

“We’re proud of the continued efforts of the entire aluminium supply chain to make cans as sustainably as possible,” said Raphael Thevenin, vice president of sales and marketing at Constellium and chair of the Aluminum Association’s Can Sheet Producers Committee.

“Aluminium cans are the most recycled beverage containers, with the best average recycled content, even though the recycling rate in the US needs improvement. 

“As we continue to find ways to manufacture more efficiently, we are in the right path to further improve the carbon footprint of aluminium cans.”

“Our analysis found that the environmental performance of aluminium cans has continued to improve in North America,” said Chris Kofler, technical director, Americas at Sphera. 

“We also determined that, sourcing of primary metal is a significant contributor to the product’s overall environmental footprint, even with the current high recycled content of aluminium cans.”

Raw material sourcing has a “significant impact” on the sustainability of aluminium can production, according to the study. 

For example, while primary aluminium sourced from Canada is made almost exclusively using renewable hydropower; Chinese primary aluminium is made largely with coal-generated power, making it far more carbon intensive.

This difference in sourcing “can have a profound impact” and “not all primary aluminium is created equal,” according to the report, which compared cans made in North America with hypothetical cans made using Canadian, Chinese or Middle Eastern primary aluminium. 

Improving recycling rates and increasing the use of recycled material in production could improve the environmental performance of aluminium cans even further. 

Each percentage increase in the end-of-life recycling rate reduces the carbon intensity of aluminium can production (cradle-to-grave) by 1.02 kg CO₂ equivalent per 1,000 cans. 

And each percentage increase in recycled content reduces the carbon intensity of aluminium can production (cradle-to-gate) by 1.43 kg CO₂ equivalent per 1,000 cans.

Recycling a single can saves 1.56 megajoules (MJ) of energy or 98.7 grams of CO₂ equivalent. This means that recycling just a 12-pack of aluminium cans will save enough energy to power a typical passenger car for more than three miles. 

The energy saved by recycling 100 percent of aluminium cans in the U.S. could power up to 4.1 million homes for a full year. This underscores the critical need for increased aluminium can recycling, which has declined in the United States in recent years.

“The results of this report again highlight how critical it is that we increase investment in recycling infrastructure in the United States,” said Tom Dobbins, president & CEO of the Aluminum Association. 

“We lose more than $800 million worth of aluminium cans to landfills each year – a tremendous loss for the economy and the environment.”

To review the full LCA report and to read additional life-cycle assessment on various aluminium products, visit www.aluminum.org/SustainabilityReports.

Like what you read? metalpackager.com/subscribe