Report shows reduction in carbon intensity of North American aluminum can production

A new comprehensive life cycle assessment (LCA) by sustainability consultancy Sphera, Arlington conducted on behalf of the Aluminum Association, 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 have dropped more than 40 percent since 1991 and 7 percent since 2012. Energy demand has declined by similar levels during this time. These reductions have been largely driven by decreased carbon intensity of primary aluminum production in North America, lighter can (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,” Raphael Thevenin, vice president of sales and marketing at Constellium and chair of the Aluminum Association’s Can Sheet Producers Committee, says. “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,” Chris Kofler, technical director, Americas, at Sphera says. “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 using renewable hydropower, Chinese primary aluminum is made with coal-generated power, making it 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 compares 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 with the average North American can, which uses a mixture of primary metal sourced domestically and abroad. Notably, an aluminum can made with only Chinese primary metal and no recycled content would be at least four times as carbon-intensive (cradle-to-gate) compared with a typical North American aluminum can, the study notes.

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 kilograms carbon dioxide (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 kilograms CO2 equivalent per 1,000 cans.

Recycling a single can saves 1.56 megajoules of energy, or 98.7 grams of CO₂ equivalent, meaning that recycling just a 12-pack of aluminum cans will save enough energy to power a typical passenger car for more than 3 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,” Tom Dobbins, president and CEO of the Aluminum Association, which is based in Arlington, Virginia, says. “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, such as 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 quantified 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 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.

Recycling a single can saves 1.56 megajoules of energy, or 98.7 grams of CO2 equivalent, meaning that recycling just a 12-pack of aluminum cans will save enough energy to power a typical passenger car for more than 3 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.