You’re standing in front of the cooler, trying to choose the perfect beer for a spring evening. But beyond the dilemma of lager versus ale lies a more serious question: bottle or can? LIME lays out the arguments on both sides.

Cans

Aluminum cans are lighter than glass bottles, so they require less fuel to truck them from the factory to your local retailer. But that’s not the whole story. Creating metal aluminum is a resource-intensive process: four to six metric tons of the mineral bauxite are required to produce one metric ton of metal aluminum. Bauxite is strip-mined in tropical and sub-tropical regions, such as Jamaica, Brazil, and Indonesia, where mining is not subject to the same level of environmental regulation as it is in more developed countries. Bauxite is crushed and put through a series of chemical processes to produce alumina powder, which is then smelted into metal. Smelters are generally located in places where energy is cheap: Alcoa, for example, is constructing a smelter in Iceland that will be powered by a massive hydroelectric project fed by a glacial river. (That project is destroying a vast wilderness area and has angered many Icelanders and Europeans.)

Environmental impacts of aluminum production include habitat destruction, toxic runoff, soil erosion, air pollution, construction of dams, and high energy use.

And because manufacturing of aluminum is a global process that requires transport of materials large distances, it offsets the benefit of needing less fuel to transport cans.

But here’s the crux: aluminum is easily recycled, and if recycling efforts were stepped up, we wouldn’t need nearly as much new aluminum. According to the Container Recycling Institute, between 1990 and 2000, Americans threw away 7.1 million tons of aluminum cans (and the number of cans being recycled is declining, rather than growing). According to CRI, that’s enough aluminum to build 316,000 Boeing 737 airplanes. What’s more, if we recycled the 50.7 billion cans we threw away in 2001, we could have saved enough energy to power 2.7 million homes for a year.

The key to making aluminum cans more environmentally friendly is to recycle them. According to EcoCycle, a nonprofit recycling center in Boulder, Colorado, recycling just one can saves enough energy to run your TV for three hours.

Bottles

Glass is made from silica sand, which is combined with limestone, dolomite, and feldspar and must be heated to more than 2700 degrees Fahrenheit. This requires huge amounts of energy consumption—which is also churning out greenhouse gases.

That said, glass is still comparatively energy efficient to produce. A measurement called embodied energy used by sustainable architects and builders, takes into account the amount of energy used to produce a material—to extract it, manufacture it, and transport it. Glass’s embodied energy is 14 times lower than aluminum’s, despite the fact that it’s heavier than aluminum.

Glass is also easily recycled, and can be made into hundreds of products, from objects such as drinking glasses to building materials like tile. Recycling glass instead of making it new cuts water use in half, reduces air pollution by 20% and slashes mining waste by 70%.

The Verdict

Glass is better than aluminum! But whichever you choose, recycling is the key. Throwing away empty bottles (plastic ones, too) is as good as saying, “Screw you, Earth and all future generations!”

Which do you choose, bottles or cans? Do you recycle either or both? Let us know where you stand!

Photo credit: King County, Washington