Image By: Pablo Päster
Dear Pablo: I have heard claims that canned beer is more sustainable than bottled. I find it hard to believe that metal is better then glass. Can this be true?
Is Aluminum Better Then Glass?
Pound for pound aluminum is much more energy intensive to mine, refine, process, transport, and shape into beer cans than glass is, so how can it be more sustainable? There are two reasons for this; weight and recycling. Aluminum cans use a lot less material than glass bottles to contain the same about of product (15 grams vs. 170 grams). So, even if the aluminum cans were ten times as energy intensive as glass bottles to produce, the cans would still represent a lower overall impact. Recycling rates for aluminum are much higher than for glass and in many locations glass "recycling" is a myth anyway. Glass is essentially made from sand and it is often cheaper for a bottle factory to make bottles from virgin material that paying to have the recycled bottles trucked all the way back to the plant. Even if the bottles are recycled, the energy required to melt the glass is virtually the same as for virgin material. When it is recycled aluminum has a much lower impact than virgin aluminum because it eliminates the mining, refining, and processing stages of the material lifecycle.The Impact Of Transportation On The Beer Footprint
Glass beer bottles weigh over eleven times more than aluminum beer cans. This extra weight adds to the transportation emissions of the incoming empties and the outgoing product. A twelve ounce bottle contains 350 grams of beer and weighs a total of 520 grams while a comparable can would weigh only 365 grams. The relationship between weight and transportation emissions is linear so the beer in glass bottles results in 1.4 times as much greenhouse gas emissions. When the empty bottles and cans are being hauled away the bottles will be responsible for 11.3 times as much greenhouse gas emissions.
What Else Is Better About Beer Cans?
Garrett Marrero, Founder and Owner of the Maui Brewing Company, told me that beer has three enemies; oxidation, light, and heat. While aluminum cans can't protect beer from heat a can provides superior protection from oxygen and light when compared to bottles. Cans also allow the use of PakTech's new reincarnation of six-pack rings, which can further reduce the potential for loss from accidentally dropped bottles or cans without a cardboard caddy or case. Why does preventing spoilage and loss make cans more sustainable? Because it allows a higher percentage of product to reach the consumer and eliminates waste.
There you have it. Beer in cans are better for the environment. Your inner beer snob can take comfort in the fact that more and more craft brewers are realizing the merits of cans. While breweries like Anderson Valley Brewing Company and New Belgium pioneered the comeback of quality canned craft brew they are rapidly being joined by others. Maui Brewing Company, Oskar Blues, 21st Amendment all have beer available in cans. Keep in mind that the most sustainable way to transport beer, aside from not transporting it at all, is in kegs. Your local craft brewery would be happy to serve you and many will even sell and fill reusable growlers for bringing their beer home.
Pablo Päster is a weekly columnist for TreeHugger.com, an experienced greenhouse gas engineer and the Senior Environmental Program Manager at Hara Software. Send your questions to Pablo(at)TreeHugger.com or submit the via this form and connect to his RSS feed.
More TreeHugger Articles On Cans:
Calling a New Six-Pack Ring "More Sustainable" Is Delusional
Soda Can Solar Panel
Couple to Wed Thanks to 400,000 Recycled Cans