Special note on acrylics
We use a lot of things made from petrol (basically, plastics) and they are probably all much better ideas than actually burning it for fuel! Rather than the processing of acrylic yarns, it's really the oil industry itself that's the bigger problem, with spillages still regularly occurring, not to mention proxy wars and the disastrous environmental effects of burning fossil fuels.
The acrylic knitting yarns we use are not manufactured in the UK but are spun under license to the familiar brands, mainly in Far East, Turkey, India, Mexico, and South America.
Unlike some imports to the rag trade, they are made in industrialised countries, in modern factories with environmental regulations. However the production of acrylics is basically a chemical industry and is bound to produce pollutants, and doubtless they are much more harmful to the environment than growing plant fibres:
"For synthetics, a crucial fact is that the fibers are made from fossil fuels. Very high amounts of energy are used in extracting the oil from the ground as well as in the production of the polymers.
"A study done by the Stockholm Environment Institute on behalf of the BioRegional Development Group concludes that the energy used (and therefore the CO2 emitted) to create 1 ton of spun fiber is much higher for synthetics than for hemp or cotton:
And a study done for the New Zealand Merino Wool Association shows how much less total energy is required for the production of natural fibers than synthetics:
Embodied Energy used in production of various fibers (MJ/kg):
SOURCE: “LCA: New Zealand Merino Wool Total Energy Use”, Barber and Pellow, http://www.tech.plym.ac.uk/sme/mats324/mats324A9%20NFETE.htm
Also to be considered is the fact that conventionally grown cotton and its processing has an extremely high carbon footprint and pollution rating. It is a crop which is grown on a huge scale and uses massive amounts of water and chemical fertiliser. I have read that the production of denim, for instance, is the most ecologically damaging of all textiles. This is a clear case where organic is superior to conventional.
It would be impossible here to detail the quantity and variety of greenhouse gases and other pollutants from the textile industry. Suffice it to say that it is huge and that the textile industry is one of the world's biggest pollluters.
The most ecologically sound way forward for conscientious knitters would be to use plant fibres, or yarn which we have personally recycled from old garments, or yarn purchased second hand. If we buy recycled yarn we should realise that reclaimed fibres involve an energy intensive process. Having looked, or should I say just glimpsed, into all this, I am now personally determined to use plant fibres or my own recycled yarns. Luckily my stash contains some Debbie Bliss ecobaby 100% Fairtrade cotton, which I bought for the previous baby in the family but didn't use. I've only got 50g (needless to say it's expensive compared with acrylics) so I'll see how it works for a tiny cardigan and socks (later: it was excellent).
Having said all this, and returning to the issue of acrylics manufacture ... aside from localised pollution, and in terms of greenhouse emissions, the manufacture of acrylics is nowhere near as harmful to the environment as transport, for instance, which in turn is not as harmful as animal husbandry. This astonishing fact has been widely debated since the United Nations Food and Agriculture Organisation published its now famous report Livestock's Long Shadow in 2006.
Though of course using such an argument is always a cop-out from the subject in hand!
On the plus side, polyester textiles made from pesky PET plastic bottles are probably an environmental benefit when you think of the tragic amount of harm to almost all ecosystems that dumped plastic bottles have caused worldwide.
However, as far as sheepless knitting goes, let's hope that the spinning of plant fibres will continue to be improved and that they will become more widely available as knitting yarn!