Cans and Bottles

Small and independent brewers in New Zealand, the US and other markets are suddenly embracing the aluminium can in a manner not completely unlike the way winemakers adopted screw caps a decade or so ago.

With wine it was pretty much all about quality. Corks were and are flawed. There may have been circumstances at play, such as improving consumer education about cork taint and maybe corks (or at least the ones being exported to the Pacific rim) were becoming less reliable. Or maybe winemakers were getting sloppy. But consumers received a clear benefit by the move to screw caps.

There were dissenters, and no doubt there still are a few. Most of that dissent was pretty flimsy and a lot of it came from the less fussy end of the market who cared more about the pop of the cork than the quality of the wine. On the other hand there were one or two reservations expressed about screw caps that had at least some scientific basis and those might still not be conclusively proven either way.

So now it's cans vs bottles. The arguments this time are a little different. There is a quality component to it, but that argument isn't nearly as one-sided as it was with screw caps. The main quality complaint with glass (light strike) simply doesn't matter if the product is handled correctly.

Broadly here they are:

• Cans are lighter so use less energy to freight.
• Cans are more easily recycled.
• It's impossible for cans to let in light.

Laid out like that, it seems like a slam dunk. So what are the dissenting arguments?

1. Bauxite mining (first stage of creating aluminium) is environmentally disastrous.
2. Cans are lined with a plastic that includes probably carcenogenic BPA.
3. Most aluminium cans that are collected for recycling in New Zealand are sent to Australia for recycling.

Oh, and there's the completely spurious “aesthetic” argument, which goes away as soon as a beer is poured into a glass, if not sooner.

What's needed is a thorough audit of environmental and financial costs for each option. Of course this is incredibly difficult. Some people in other geographies have had a crack (this article in Slate magazine seems a reasonable attempt) and have generally come to the conclusion that: (1) draft beer is best, (2) bottles are next best for sales to customers who are geographically close and (3) cans are better than bottles if long haul freight is involved.

What might be different in New Zealand? Well as a country with a lot of coastline you'd think that the raw ingredients for glass bottles must be pretty abundant. It looks as if most or all of our glass is created from sands collected from Parengarenga Harbour in Northland. From the lay person's point of view, it would appear that the raw material is just lying there waiting to be collected and is not in any danger of running out.

Meanwhile aluminium relies on bauxite from Australia. Here's what Lagunitas brewery have to say about bauxite mining. We bring bauxite to Tiwai Point and throw cheap electricity at it. Apparently the smelter pays one quarter what the rest of us do for their power. The Manapouri power station that generates electricity for Tiwai Point was one of the most controversial construction projects in New Zealand history on account of its impact on the environment. It seems the taxpayer also subsidises 90% of the smelter's carbon credits. When the smelter's operators threatened to close the whole operation down a few years ago, there was speculation that this would free up so much electricity generation that New Zealand would effectively be flooded with cheap electricity (although I'm told that there isn't enough capacity in our transmission network to bring that electricity to the North Island in the short term). In the end we used extra taxpayer money to persuade them to stay open until well after this year's election.

In other words, we seem to create aluminium in New Zealand as one giant, taxpayer funded work scheme with possibly huge environmental costs.

Then there's reuse and recycling. This is where aluminium should be the big winner. Except that we aren't quite as good at recycling aluminium as we are glass, but only by 48% compared to 50%. But it's the recycling process where aluminium is much better, using a fraction of the energy that went into production to be recycled. There seems to be one anomaly in the whole thing though – most of our used aluminium gets sent to Australia and recycling only contributes a tiny portion to the production at Tiwai Point.

What I don't understand here is why we went from reusing glass to recycling it. You would think that cleaning a bottle would use a fraction of the energy needed to crush or melt it then reconstitute one. Does the glass weaken over time? Did drinks producers insist on having unique bottles? Reuse lives on in the old fashioned flagon (a.k.a. growler), although that has been superceded partly by the more modest rigger, which has the same benefit of reuse.

But I really would like to know what stops us having a bottle collection network that drink makers source their bottles from. I suspect it comes down to quality, but maybe a bit of determination would solve that. It's good enough for home brewers after all. It would be interesting to see one of our local breweries experiment with crediting customers for returning bottles.

Finally there's the BPA thing. Getting into really tricky science here, so I'm not going to pretend to know what's best. Do New Zealand made cans even have the same lining as foreign ones? I know I'm not going to risk eating beer-can chicken any time soon.

There's a case for saying that the current fashion for the can needs a big injection of scepticism. Or maybe these reservations will go up in smoke in the light of some really good facts and figures. Comments welcome.