A new comprehensive Life Cycle Assessment (LCA) by sustainability consultancy Sphera shows that the carbon footprint of aluminum cans made in North America has dropped by nearly half over the past three decades. The Life Cycle Assessment of North American Aluminum Cans found that greenhouse gas emissions for aluminum beverage can production has dropped more than 40 percent since 1991 and 7 percent 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 aluminum production in North America, lighter cans (which are 27 percent lighter per fluid ounce compared to 1991) and more efficient manufacturing operations.

A graphic summary of the report’s key takeaways is available here. 

“We’re proud of the continued efforts of the entire aluminum 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. “Aluminum cans are the most recycled beverage containers, with the best average recycled content, even though the recycling rate in the U.S. 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 aluminum cans.” 

“Our analysis found that the environmental performance of aluminum 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 aluminum cans.”

Raw material sourcing has a “significant impact” on the sustainability of aluminum can production, according to the study. For example, while primary aluminum sourced from Canada is made almost exclusively using renewable hydropower; Chinese primary aluminum 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 aluminum 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 aluminum. Even assuming 73 percent recycled content, a can made with primary aluminum sourced in China would be almost twice as carbon intensive compared to the average North American can, which uses a mixture of primary metal sourced domestically and from several other countries. Notably, an aluminum can made with only Chinese primary metal and no recycled content would be at least 4 times as carbon intensive (cradle-to-gate) compared to a typical North American aluminum can.

Improving recycling rates and increasing the use of recycled material in production could improve the environmental performance of aluminum cans even further. Each percentage increase in the end-of-life recycling rate reduces the carbon intensity of aluminum 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 aluminum 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 aluminum cans will save enough energy to power a typical passenger car for more than three miles. The energy saved by recycling 100 percent of aluminum cans in the U.S. could power up to 4.1 million homes for a full year. This underscores the critical need for increased aluminum 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 aluminum cans to landfills each year – a tremendous loss for the economy and the environment.”

In a recent letter to Congress and newly released policy framework, the Aluminum Association recommends that Congress establish and fund a recycling infrastructure program, like those in the RECOVER Act, as part of a broader infrastructure package. 

The Life Cycle Assessment of North American Aluminum Cans report was commissioned by the Aluminum Association to update a previous study published in 2014. The study tracks aluminum cans manufactured in North America and quantifies all material, energy use and potential environmental impacts over the life cycle of 1,000 cans from raw material acquisition through recycling and/or disposal. 

The study considers both the cradle-to-gate (raw material extraction to finished cans) and cradle-to-grave (raw material extraction to end-of-life disposal or recycling) carbon footprint of aluminum cans. Cradle-to-gate analysis is most sensitive to the recycled content and/or primary aluminum used in can production while cradle-to-grave analysis is most sensitive to end-of-life recycling rates. The report assumes a weighted average can size of 13.6 fluid ounces, metallic weight of 12.99 grams, recycled content of 73 percent and end-of-life recycling rate of 50.4 percent. 

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