Which kills the earth quicker: cans or bottles

April 25, 2008 7:59 AM

I drink a lot of diet soda. I tend to buy it in one of two formats: 12-packs of aluminum cans (which come in paperboard cartons), and individual two-liter bottles. If I were to buy one format exclusively and recycle the packaging, which would be the greener choice?

I recycle all my cans, bottles, and paperboard. I know that reducing consumption of these things would be better all the way around. I get that. But, assuming consumption remains the same, would there be any environmental benefit to choosing one (exclusively) over the other. I'm assuming that 20-oz bottles (which are expensive anyway, so I don't buy them at the grocery store) are the worst of all possible worlds. Other thoughts on flavored water transportation methods are welcome, of course.

Diet soda is primarily a caffeine delivery method. Perhaps shifting to coffee or tea (brewed at home or work + my own cup) would be the best bet. Or, gasp, I could learn to like water. Stats would be great, but this isn't for a paper or anything. I'm just a curious consumer, trying to be a slightly less evil consumer.

posted by wheat to food & drink (32 comments total)

I have previously read that aluminum is by far the more easily recycled of the two container types you're asking about, but I don't have stats or cites.
posted by OmieWise at 8:01 AM on April 25

I seem to recall that for virtually all recyclable materials other than aluminum, it takes more energy to recycle than to make again from scratch. I'm led to believe this, if only because I can't think of any other material you can get paid to recycle.

I'd say that the cans are probably a greener choice, should you actually recycle them.

Alternately, I do like to brew my own iced tea in the fridge -- I just put a couple of teabags in a bottle or a cup of cold water and leave it in the fridge overnight. Because you're using cold water instead of hot, all the bitter chemicals don't wind up in your tea (they're only soluble in hot water) and so you wind up with a delicious and refreshing savory tea that isn't bitter.
posted by DoctorFedora at 8:15 AM on April 25 [5 favorites]

IMO, if you're serious about the environmental impact of drinking that much diet soda, then any difference in packaging recycling is likely dwarfed by the energy required to transport it. It's like wondering whether its better for the environment to get real leather or vinyl for the interior of your SUV.
posted by mkultra at 8:16 AM on April 25

Yeah, tea and water wins over diet soda any day on the environmental front from a packaging perspective. I'd be interested to hear about the eco impact of tea growing and transport, though. That might even things out a bit...

Oh, and if you care about osteoporosis, cola of any kind, diet or not, is bad.
posted by Deathalicious at 8:19 AM on April 25

Check the Wikipedia for Aluminum Recycling versus the one for Glass Recycling. Unfortunately many of the stats are uncited, but the one that swayed me to buy in aluminum when I could isn't listed: that an aluminum can that goes into the recycling bin is back on the shelves in less than 60 days.
posted by 1f2frfbf at 8:22 AM on April 25

This "Fact Sheet" PDF from the University of Florida compares the energy requirements for cans versus bottles and concludes that cans are better. There aren't any citations and the conclusions are a little hand-wavey, so you might want to take it with a grain of salt. The crux of the issue is that aluminum cans are recycled in other aluminum cans, while plastic bottles can only be recycled into other things. The issue of cardboard packaging isn't dealt with, but it can be recycled into more cardboard packaging a number of times before the fibres are too short to be used again.
posted by ssg at 8:30 AM on April 25

isn't listed: that an aluminum can that goes into the recycling bin is back on the shelves in less than 60 days.
posted by 1f2frfbf at 11:22 AM on April 25

I've said it about a dozen times in various threads. Of any recycled product anywhere, aluminum recycling is far and away the most green. Aluminum recycling uses less water and energy than all other recyclings, and in fact uses less water and less energy than aluminum mining, which is why aluminum companies are desperate to get people to recycle their aluminum. 40 recycled cans saves a gallon of gas. Al can recycling is nearly at the level of reuse, which is the greenest possible option.

Coke is experimenting with aluminum bottles to replace 20oz plastic as oil has risen relative to Al. Plastic is extremely difficult to recycle, and the entirely of the bottle is not recycled - there are waste products.

Also, plastic comes from oil, and most of that comes from places that we are fighting wars over and we collectively have no regulatory influence over. A great deal of aluminum comes from the US, and Al companies have to adhere to US environmental, labor, and mining laws.

I'm not sure about the paper packaging, so the more eco friendly option might be to buy it by the case of 24, rather than 12.
posted by Pastabagel at 8:44 AM on April 25 [4 favorites]

it's my (possibly mistaken) understanding that the plastic used in two liter bottles is actually a petroleum product itself.
posted by toomuchpete at 11:25 AM on April 25

Almost all plastic in consumer products comes from oil. And all plastic used for packaging comes from oil. 40% of the oil consumed in the U.S. is not fuel or burned, but rather is used for chemicals the fast majority of which are plastics. To recycle plastic, you need organic solvents (as in organic chemicals, not organic food). Guess where the solvents come from. That's right, oil. In addition to solvents, you also need heat, and heat comes from burning oil.

Another way to think of it is this: all of the aluminum atoms that have ever been on the earth is still on the earth, either as a metal or as part of a compound. We don't really use up aluminum. If we all threw them away into a landfill we could potentially mine landfills for aluminum. Paper is basically cellulose. And there are insects that will happily eat the paper. The only problem is paper is the oil-based inks, bleaches, and binders used in the paper together.

But plastic comes from oil and does get used up. The oil that comes out of the ground isn't replaced when you toss a plastic bottle. Because chemical reactions often produce heat as a by-product or require heat to start or as a catalyst, there is a net loss.

So other things being equal, chose the metal package or the paper package over the plastic. Don't drink water from bottles, carry a refillable aluminum bottle.
posted by Pastabagel at 8:57 AM on April 25 [4 favorites]

A lot of talk about the energy and such required to recycle them, but what about the energy and resourced to manufacture them? Between a bottle and a can, which one takes the least resources to manufacture and transport to the end location?
posted by dripdripdrop at 8:59 AM on April 25

Seems like the most packaging/energy efficient way to get soda would be to forgo the single serving packages all together. Instead, buy the bulk syrup and get one of the dispensers used in fast food joints. Hundreds of servings exist in one of those packages and you're not paying to transport all the water if you use the tap.

That said, if I found myself buying a soda fountain I'd probably start re-evaluating whether I should be drinking the stuff at all.
posted by roue at 9:09 AM on April 25 [1 favorite]

Why not get a soda-stream machine? Then you don't have any waste, nothing to recycle, no energy is wasted transporting the soda to the store (and again to your home), consequently you save a lot of money, and you get as much soda as you can drink. To go even more green, get a second-hand one :)

Warning: A friend of mine got a soda-stream machine, and noticed after a while that the easy access to perpetual unlimited soda had considerably increased the amount of it that he drank. (He eventually decided to cut back to the levels he used to drink)
posted by -harlequin- at 9:10 AM on April 25

Aluminum is extremely energy intensive to refine, so it loses on that end, but transportation costs should be a wash, since most of the weight you're transporting is the liquid inside.
posted by electroboy at 9:12 AM on April 25

mkultra: I have to transport myself to work every day, so the soda rides shotgun. I bring a 12-pack with me when I run out (maybe twice a week, more or less). I don't think the weight of a 12-pack or a 2-liter bottle would make much difference. I know that this single change will not have a tremendous impact. But small changes over time do have some impact. That's what I'm after here. This switch is not the sum total of my efforts to have less impact on the environment.

But thanks for the holier-than-thou effort to stifle my intellectual curiosity and desire to do something better, albeit not perfectly. If you think the question is stupid, or pointless, why bother answering? Comments like yours are why I'm increasingly cautious about asking anything here. Filtering through the snark gets old.
posted by wheat at 9:22 AM on April 25

Previously. And shipping water around is a huge waste of energy because it's heavy. Drinking tea would certainly be more efficient than drinking from cans or bottles, assuming you buy dried tea leaves and use water from your tap. Also a lot of these types of 'which is greener' questions depend on where you are. Your municipality might collect 2L plastic bottles, but we don't know if they end up in landfill, are incinerated to produce electricity, spun into fleece, or burned in a pit. That said, aluminum is expensive, and your municipality probably does recycle it.
posted by kamelhoecker at 9:25 AM on April 25

DoctorFedora: this might work for me. I like iced tea, and I have access (at home and work) to a fridge.
posted by wheat at 9:29 AM on April 25

Thanks for positing this question. I was just wondering about this very topic today. I know that I am going to drink diet pop (coffee/tea is too strong for me) and thought, all things being equal can I make a better choice. I always figured that the bulk of 2L bottles was better but will now switch to cans. Thanks!
posted by saradarlin at 9:33 AM on April 25

To be fair, I think mkultra was not talking about energy expenditure for *you* to transport it, but for transporting the cans or bottles from the manufacturer to your point of purchase.

I went through a similar internal debate last year, realizing that the environmental impact of getting single servings of chemicals that weren't very good for me was just too unpleasant to contemplate. At that point I decided to only drink diet coke if I found myself in a restaurant or movie theater or someplace where I could buy it as a fountain drink. After a while, I just lost the taste for it altogether and no longer find it appealing at all. In fact, I bought a bottle in the airport this weekend, as I'd had two hours of sleep and needed some quick caffeine, and found I couldn't drink more than two sips.
posted by judith at 9:49 AM on April 25

Aluminum recycling uses less water and energy than all other recyclings, and in fact uses less water and less energy than aluminum mining, which is why aluminum companies are desperate to get people to recycle their aluminum.

Aluminium isn't mined; bauxite is mined. And the mining of bauxite, due to commonly high ore grades, isn't very energy intensive. Neither is refining bauxite into alumina. But turning alumina into aluminium (smelting) is the goocher.

/pedant
posted by Kwantsar at 9:54 AM on April 25

Another twist, I think most soda is bottled locally, so the transportation distance is pretty small, whereas bottled water is shipped from wherever the source is (i.e France, Fiji, Pennsylvania). So in that case, soda is more environmentally friendly than water.
posted by electroboy at 10:08 AM on April 25 [1 favorite]

And I shouldn't say that the Bayer process, which turns bauxite into alumina, isn't energy intensive. It's just not nearly as energy-intensive as the subsequent smelting into aluminium. Figures are here (among many other places) in a .pdf if you care.
posted by Kwantsar at 10:11 AM on April 25

If you're looking for the most efficient caffeine delivery method, skip the liquids and just take caffeine pills.
posted by randomstriker at 10:19 AM on April 25

wheat- Judith's take is correct, no need to be an ass. You yourself
noted that perhaps tea is the best rout, which is what I'm getting at- you're dwelling on ultimately trivial differences when there are ways to get your fix at a fraction of the impact.
posted by mkultra at 11:55 AM on April 25

> Another twist, I think most soda is bottled locally, so the transportation distance is pretty small, whereas bottled water is shipped from wherever the source is (i.e France, Fiji, Pennsylvania).

This is true if you're buying "spring water" that has to actually come from a spring, or if the water specifies a particular source. However, the Dasani and Aquafina bottled waters are just made at the same bottling plants where they make Coke and Pepsi. They just run the same intake water through a R-O filter and bottle it, adding some herbs & spices in the case of Dasani.

I'm not sure if every Coke/Pepsi bottling plant has the R-O filters necessary, but they were working on deploying them to all the major ones last time I researched the issue.

Obviously having a Nalgene or aluminum water bottle and filling it from a filter would be the best option (and hey, if you need caffeine, there's always No-Doz!), but I'm not sure that commodity bottled water is that much worse than the same quantity of soda.

Getting back to the original question, the evidence for aluminum seems pretty strong, although I think the friendliest caffeinated-beverage option would be the one you make up at home and then put in a reusable bottle. Personally, I like iced coffee: I'll brew up a pot the night before, stick it in the fridge, and in the morning add milk and sweetener and put it in a Thermos to keep it cold. It's just as good as those little bottles of Starbucks, and probably about a thousand times cheaper.

(Incidentally I wonder where glass recycling stacks up compared to aluminum...)
posted by Kadin2048 at 11:58 AM on April 25

But thanks for the holier-than-thou effort to stifle my intellectual curiosity and desire to do something better, albeit not perfectly. If you think the question is stupid, or pointless, why bother answering? Comments like yours are why I'm increasingly cautious about asking anything here. Filtering through the snark gets old.

You owe mkultra an apology. As Judith points out, unless you're canning that stuff yourself the transport once you acquire it isn't the point. Liquid is heavy, and the transport of it in individualized containers is costly. This is one of the two core points with regard to the problem with bottled water, which you can find plenty of websites addressing the issue without any real difficulty.

If you're willing to substitute apples for oranges (so to speak) in your consumption - and you indicated you might - then it's a very valid point. Water is delivered to your home through an infrastructure that's already in place and highly efficient, assuming you don't get well water. Soda on the other hand, comes to you in some variation of the following process:

Highly concentrated syrup is shipped in big plastic drums to a local bottling plant. I'm pretty sure most plants don't re-use the containers, in no small part because I just bought 4 of them from my local Pepsi plant a few weeks ago to use as rain barrels. So there's a shipping cost associated with those 55gal drums not to mention their manufacture. While I and others may put them to an environmentally positive use, they never the less exit the soda production system and are not re-used.

The bottling plant then does their magic (which consumes power) to create the drinkable potion and jams it into cans and (I presume) packages them there. From there they're shipped either to a shop that sells them or to a distributor who will take them one more step to your retailer.

The big drums might be brought some of their distance via a lower cost rail method but the final stage is via trucks using refined petroleum fuel. You might alter your impact on the packaging by 10% either way but that pales in comparison to not consuming it at all.
posted by phearlez at 12:07 PM on April 25 [2 favorites]

Recycling aluminum will probably be the winner in most scenarios just from the perspective of the most energy-saving type of recycling. Of course replacing consumption is going to be superior if it replaces any packaged beverage predominantly with tap water, which comes via an incredibly efficient transport system (and is the main ingredient in what you drink regardless, so basically it's just a straight gain by eliminating all the manufacturing and product transportation energy).

I seem to recall that for virtually all recyclable materials other than aluminum, it takes more energy to recycle than to make again from scratch.

Flatly incorrect. Source, source, source.
posted by nanojath at 12:58 PM on April 25

phearlez: All mkultra added to the discussion was attitude. I can find that anywhere for free. I owe him nothing. If transportation costs to the retailer are relevant, so be it. I found his comment belittling and insulting. Hence my reaction.

You might alter your impact on the packaging by 10% either way but that pales in comparison to not consuming it at all.

You're probably right. But that wasn't my question. I didn't ask "How can I drastically reduce my consumption." What I asked was, If I'm going to do this anyway, will one of these choices be better than the other. I've gotten some fine answers to that. If I can alter my impact 10% to the good, I'd call that a good thing. The gist of mkultra's comment was that there was no point in bothering: that the premise itself was stupid. I take objection to that.

But the answers, yours included, have helped me to see that consuming this beverage is more wasteful than I had originally thought. So I am going to try switching to tea, as a more economical and green alternative.
posted by wheat at 1:43 PM on April 25

While I and others may put them to an environmentally positive use, they never the less exit the soda production system and are not re-used.

You have no idea whether that's true, so why claim it is?
posted by electroboy at 2:06 PM on April 25

All mkultra added to the discussion was attitude.
...
The gist of mkultra's comment was that there was no point in bothering: that the premise itself was stupid.

Dude, you're reading way too much into things. You might want to consider why you're having such a viscerally negative reaction, especially when your very question opens the door to that answer:

Other thoughts on flavored water transportation methods are welcome, of course.

Diet soda is primarily a caffeine delivery method. Perhaps shifting to coffee or tea (brewed at home or work + my own cup) would be the best bet..
posted by mkultra at 4:05 PM on April 25

Drink Green Tea, it is good for your teeth, and its full of antioxidants, has caffeine, and it tastes pretty good. Also from an environmental perspective you are much better off overall. due to a much less involved production process.

Water is the healthiest option for you.
posted by BobbyDigital at 8:03 AM on April 26

Seven misconceptions about plastic recycling.
posted by oneirodynia at 10:32 AM on April 26

While I and others may put them to an environmentally positive use, they never the less exit the soda production system and are not re-used.

You have no idea whether that's true, so why claim it is?

I'm not saying that they're never re-used anywhere for anything - I'm saying strictly with regards to soda manufacture they're not re-used. So while every single one they sell off at a nominal cost (as all three of the closest plants to me do) might go on to a great cause, when they next need 55g of syrup they will consume another plastic barrel.

You can be sure that when it becomes cheaper to ship them back and wash them and re-use them they'll start doing it, but all indications are that at the moment every 55g drum used is used only once within that system and making more soda will require making more drums.

If transportation costs to the retailer are relevant, so be it. I found his comment belittling and insulting. Hence my reaction.

His comment was matter-of-fact and impersonal, and your reaction was inappropriate and rude. Don't worry though, I think he has likely learned the same lesson I did and will refrain from interacting with you again.
posted by phearlez at 12:52 PM on April 26

I've thought over this thread and my initial response to mkultra, and I think I simply over-reacted. I don't think he intended to offend anyone, and his point about transportation costs is relevant to the discussion. So, sorry for that, mkultra. Please accept my apology.

As to you, phearlez, I don't believe I was rude to you personally. If you review my contributions here, you'll find I'm generally helpful, so adding me to your killfile based on this thread would be premature, though that's your choice, of course.

As for the thread itself, I've decided to drink up my current stock of soda then switch to tea. I'm going to try DoctorFedora's cold-brewing method and see how I like that. So, unless the environmental impact of tea production is also problematic, perhaps I'll have made a healthy switch, on a lot of levels.
posted by wheat at 9:52 AM on April 27