Cans vs. Bottles - Which is better?

Like everyone else, I have noticed that more and more beers are sold in cans.  Craft beers in cans seem to be the new fad.  When I was out in Colorado last November, I asked at one bar "what they had in bottles."  The server gave me a very dirty look and said they only have cans.  To me can or bottle was not the point; I just wanted to know what else they had since I had tried all the draft beers.  But this got me thinking, why the switch to cans?  Based on that experience I was guessing it was some type of benefit to the environment.  So I decided to do some research to find out.

As I looked into this, it turns out that breweries have a lot of reasons to switch to cans from bottles.  Cans keep more light out, they are lighter and less expensive to ship than bottles.  For small breweries they are less expensive to buy and they don’t have a separate labeling process.  People can take a can into more places since glass bottles are banned some places.  In addition a number of places listed that it is better to use aluminum because it is less energy to recycle compared to glass. 

Then I found some drawbacks.  OK, really just one.  All the cans have to be lined to prevent the beer from picking up a metallic taste.  The liner is a form of epoxy and contains BPA.  Now, the EPA says that the level of BPA in each can is pretty low and therefore should not be an issue.  But BPA is linked to cancer and other diseases.  To me, this seems like a pretty big drawback.  Maybe the energy savings offset this?

So, I decided to look into the energy use and recycling of cans and bottles.  It was very easy to find out that it is much more energy efficient to recycle aluminum than to create new aluminum from bauxite.  It takes 5% of the energy to recycle it as to create new.  So that’s a great benefit!  However, I also found out that only 30% of aluminum is recycled.   Mining new bauxite to create aluminum destroys rain forests and uses a lot of energy.  But I guess saving on 30% is better than nothing. 

I wanted to compare that to bottles.  In research, I found that Bottles contain no BPA, except for the liner in the cap.  A much lower amount than in the can, but still some BPA so that is not the best news.  

On the energy side, it is again a different story.  To recycle glass bottles, it uses 50% less energy than to create new.  So Aluminum is a 95% reduction and glass is only a 50% reduction.  Glass has a 80% recycle rate compared to aluminum’s 30%.  This was all great information, but I had no idea what the numbers added up to.  80%, 30%, 50% of what?!

I needed to find out how much actual energy is needed to create each one.  After doing some research, I found that it takes (on average) 79,000 watt hours to create 1 kg of aluminum cans today and 5800 watt hours to make 1 kg of glass beer bottles.  That is a big difference!  Then I remembered that a can weighs a lot less than a bottle.  After you account for the difference in weight of each one can takes 1119 watt hours to create and one beer bottle takes 1154 watt hours to create.  So a can saves 35 watt hours.  That is 119 btus, or about 1/10 of a cent at current energy prices.  That is not a big difference per can/ bottle.  You figure on some waste and that these are averages and they basically use the same amount of energy. 

After all of that, it appears that the real difference comes down to saving the brewery some money on shipping.  Once you factor in the BPA, I am not sure it is really worth the little bit of energy savings.  I am sure others will disagree, but I think I prefer to stick with bottles.