Single-use plastic bottles vs reusable bottles
Like bags, single-use plastic bottles are facing a reckoning. The most common material in plastic bottles is polyethylene terephthalate (PET), which is made from petroleum and natural gas.
Thankfully, plastic bottles are widely recyclable, but out of the 35.8 million plastic bottles used every day in the UK, only 55% are recycled. That’s 16 million bottles a day being added to landfill, littering our streets, or breaking up into microplastics in our oceans. (Psst… Norway recycles 97% of all their plastic bottles. Let’s take a leaf out of their book!)
Also, when a bottle does get recycled, virgin plastic usually gets mixed in to maintain the quality of the plastic; even then, plastic can only be recycled a finite number of times before it degrades to the point of being unusable (Nat Geo).
But what about their carbon footprint, and how does it compare to reusables bottles?
A litre-sized plastic bottle will have an average carbon footprint of approximately 103g CO2e, which comes from the PET and the energy necessary to mould it into its bottle shape (How Bad Are Bananas).
The carbon footprint of a reusable bottle will depend on what it’s made from. An MIT article found that a reusable bottle made out of virgin aluminium weighed in at 5.705kg CO2e per pound of material. The study goes on to estimate that it would take between 10 to 20 uses for a reusable bottle, depending on the material, to break even with the impact of a plastic bottle (when the source of the water is taken out of equation – that’s a whole ‘nother kettle of fish).
However, a New York Times article that examined the life cycle assessment (LCA) of a 300 gram stainless steel water bottle came up with a higher number. If the stainless steel bottle replaces 50 plastic bottles, it will have a lower carbon intensity than its plastic counterpart. But in order for it to beat plastic in all environmental impact categories, it’ll have to be used 500 times.
Also, though stainless steel and aluminium are 100% recyclable, bottles made from these materials tend to be also harder to recycle than plastic bottles, as they’re likely made up of several different kinds of materials fused together (for example, if there’s plastic embedded into the metal cap).
But unlike plastic, steel and aluminium can be recycled an infinite number of times, so if you need a reusable bottle, your best bet will be to get one that’s made entirely out of that material, to make it easier for you to recycle at the end of its life.
Conclusion: We need to ditch single-use products because they’re made from fossil fuels and, when improperly disposed of, can harm our natural environment. However, they do have a lower carbon footprint than reusable products. Therefore we need to reuse what we’ve already got as many times as we can and try to recycle it once we’re done with it.