Saturday, October 4, 2008

Plastic bottles vs glass bottles vs aluminium (aluminum) bottles

I read an article today that said that it takes 1/5th of a litre of crude oil to make a plastic bottle. I've been wondering about glass vs aluminimum vis plastic so I did a quick scan around the web. This is what I found from the various propaganda out there.

  • Aluminium and glass seems to have higher embodied energy per litre of cotents than PET (plastic bottles) although I found a lot of conflicting information on this. I assume that's because glass is heavy, and that aluminimum is energy intenstive to make. (Embodied energy is a proxy for embodied carbon dioxide.
  • Reusing alumnimum cans apparently results in saving around 90% of the energy of producing those cans in the first place. This is only around 20% for glass (assuming the glass is reprocessed and remanufactures rather than reused in it's original shape).
  • Only 35% of PET bottles get recycled in Australia.
  • PET bottles are suspected to break down and cause nasty neurological and hormonal toxins when they are put into landfill, or resued for an extended period. There is much mixed information and potential misinformation about this, so as a general rule I avoid reusing them.
  • CO2 footprint is really driven by the distance travelled by the bottles when they are full because that's when they have greater weight.

My conclusions thus far

  • None of the packaging sounds very good.
  • Recycling rates are poor. The real way to avoid toxics and save CO2 is to recycle everything - take it home with you if you can't find a recycling bin.
  • If you are serious about saving the planet, drink tap water whenever you can intstead of buying the bottled stuff.