Lots of people are concerned about the transportation costs of shipping fabric from China to the US, because they think the shipping contributes to an enormous carbon footprint of, say, cotton fabric. The thinking goes that the homegrown variety (which doesn’t have the transportation burden) is far preferable because you save so much by not having to ship such long distances.
Well…A wise guy once said that green is not black and white.
An article which appeared in the New Yorker magazine by Michael Specter entitled “Big Foot” describes how easy it is to confuse morality and science. It turns out that the carbon accounting thing is extraordinarily complex and often counterintuitive.
Mr. Specter quotes Adrian Williams, an agricultural researcher in the Natural Resources Department of Cranfield University in England: “The idea that a product travels a certain distance and is therefore worse than one you raised nearby—well, it’s just idiotic,” he said. “It doesn’t take into consideration the land use, the type of transportation, the weather, or even the season. ” He cites as an example the environmental burden imposed by importing apples from New Zealand to England. New Zealand apples can have a smaller carbon footprint than those raised 50 miles outside London because in New Zealand they have more sunshine than in the UK, so the yield is higher and energy needed to grow the crop is correspondingly lower. Also electricity in New Zealand is mostly generated by renewable resources, none of which emits large amounts of CO2.
Turns out that that applies to natural fibers and fabrics also.
We found two reliable LCA studies – one done by Patagonia (for finished products) and another by the the Stockholm Environment Institute (entitled “Ecological Footprint and Water Analysis of Cotton, Hemp and Polyester”) , which both found that transportation costs account for only about 1% of the total energy used. Resources used to produce the fibers require by far the greatest amount of energy. Patagonia’s Director of Sustainability, Jill Dumain, is quoted in the WSJ “Six Products, Six Carbon Footprints”, as saying that “there’s a lot of reasons to have a tight supply chain, but environmentalism isn’t one of them.” By far the largest part of the footprint is from the production of the fibers. And the situation is further complicated by organic vs. conventional production – it’s not always true that organic (in terms of carbon footprint anyway) is always better. In fact, the study done by the Stockholm Environment Instutite found that the total ecological fooprint, measured in global hectares, to produce one ton of spun fiber is higher for organic cotton grown in Punjab, India than that of conventionally produced cotton grown in the USA. That’s due to the poor yields in Punjab, meaning they need more land to produce the same amount of fiber – therefore greater resource use.
Polyester, the most popular fiber in the world, also has the largest carbon footprint – by a factor of about 4! But that’s the next blog.