Why cotton bags may not be as green as you think
Are Cotton Bags More Environmentally Friendly Than Plastic Bags?
If you are trying to live sustainably and limit the environmental impact of your everyday living then reusable bags are most likely already firmly on your radar. Plastic bags have become taboo, and we all know single-use plastic is bad for the planet. Most of us also know that the biggest impact we can make is by buying less stuff and using the things we do buy as many times as possible.
But… while plastic bags are ending up in our oceans, are very obviously made from non-renewable resources and do not biodegrade these are not the only factors that need to be considered when looking at the environmental impact of our shopping bags. And when all things are considered the results might surprise you.
Which reusable bags are the most eco-friendly?
Firstly, and this is very important, the most eco-friendly option is the bag you already have! That could be a “single-use” carrier bag, as there’s no reason at all you shouldn’t reuse it many times before you eventually recycle it, any other plastic bag, a cotton tote, a jute shopper, a woven basket, a box (because your groceries won’t care in the slightest) or even an old t-shirt.
Before you think about buying something new have a look at what you already have. There are some great tutorials for turning an old t-shirt into a tote bag, you just need a pair of scissors and don’t even have to sew anything. And any bags you do have should be being used and used before you start buying new ones.
The same goes for anything else you might have as an alternative to single-use items. Your reusable coffee cup or water bottle, your tubs and boxes for food storage and lunches, and your shampoo bottles.
How many times do you need to reuse your bag before it’s better than a plastic one?
The thing about reusables is that they generally take more energy and recourses to make them. This means that you HAVE to reuse them or they are in fact worse for the planet than the single-use items they are intended to replace.
A 2018 Danish study looked at how many times different types of reusable bags would have to be reused to make them better over-all than a single-use HDPE bag. And you might be surprised by the results.
The study showed that cotton bags would need to be used 7100 times before having a better environmental impact than plastic and reusable plastic and paper bags requiring between 35 and 85 uses, which seems a little unrealistic for paper.
A similar UK study just looking at the Global Warming Potential (GWP) produced lower results with a cotton bag requiring 131 reuses, paper 3 reuses and a non-woven Polypropylene (PP) requiring 11 reuses. This clearly shows that what you include in the study dramatically affects the results.
It is interesting to note that the biggest contribution to the poor results of cotton was the fossil fuel requirements for transportation and irrigation and that neither study looked at the cost of plastic bags ending up in our oceans and what it might cost to remove it.
What about Jute?
Jute bags were not included in either of these studies but we are able to make some comparisons.
Compared to cotton jute is less energy-intensive to grow and generally doesn’t require irrigation. In fact according to Defra Jute has a lower environmental impact in energy use, water use, greenhouse gases, wastewater and land use. Obviously there are many other factors to consider but we feel jute is a good choice environmentally.
Next up: What are jute bags?